Merge branch 'master' into copilot/visualize-mouse-movements

Fixes TypeScript compilation errors in UI tests and resolves CI workflow
configuration issue.

## Changes Made

### 1. Fixed expandTopic parameter order in ui-tests.spec.ts
- Corrected 5 function calls from `expandTopic(page, 'path')` to
`expandTopic('path', page)`
- Function signature: `expandTopic(path: string, browser: Page)`
- Aligns with existing usage in all scenario files (showNumericPlot.ts,
publishTopic.ts, etc.)

### 2. Fixed CI workflow configuration
- Updated `.github/workflows/tests.yml` to checkout PR code instead of
base branch
- Added `ref: ${{ github.event.pull_request.head.sha }}` to all 4
checkout actions
- The `pull_request_target` event defaults to checking out the base
branch; this fix ensures CI tests the PR's code

## Root Cause

The CI workflow was testing the base branch (master) which still had the
wrong parameter order, while the PR had the correct fix. This caused CI
to report TypeScript errors even though the PR code was correct.

## Testing

- ✅ TypeScript compilation passes locally (`tsc` and `yarn build`)
- ✅ Parameter order matches function signature and codebase conventions
- ✅ CI workflow now correctly tests PR code
- ✅ All 4 CI jobs (test, ui-tests, demo-video, test-browser) will use
corrected code

<!-- START COPILOT ORIGINAL PROMPT -->



<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>Fix tests</issue_title>
> <issue_description>- fix backend tests
> - fix UI tests</issue_description>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>



<!-- START COPILOT CODING AGENT SUFFIX -->

- Fixes thomasnordquist/MQTT-Explorer#935

<!-- START COPILOT CODING AGENT TIPS -->
---

✨ Let Copilot coding agent [set things up for
you](https://github.com/thomasnordquist/MQTT-Explorer/issues/new?title=✨+Set+up+Copilot+instructions&body=Configure%20instructions%20for%20this%20repository%20as%20documented%20in%20%5BBest%20practices%20for%20Copilot%20coding%20agent%20in%20your%20repository%5D%28https://gh.io/copilot-coding-agent-tips%29%2E%0A%0A%3COnboard%20this%20repo%3E&assignees=copilot)
— coding agent works faster and does higher quality work when set up for
your repo.

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: thomasnordquist <7721625+thomasnordquist@users.noreply.github.com>

.devcontainer/devcontainer.json

@@ -0,0 +1,46 @@
+{
+  "name": "MQTT Explorer Development",
+  "dockerComposeFile": "docker-compose.yml",
+  "service": "app",
+  "workspaceFolder": "/workspace",
+
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "dbaeumer.vscode-eslint",
+        "esbenp.prettier-vscode",
+        "ms-vscode.vscode-typescript-next",
+        "ms-azuretools.vscode-docker",
+        "eamodio.gitlens"
+      ],
+      "settings": {
+        "editor.formatOnSave": true,
+        "editor.defaultFormatter": "esbenp.prettier-vscode",
+        "typescript.tsdk": "node_modules/typescript/lib",
+        "editor.codeActionsOnSave": {
+          "source.fixAll.eslint": "explicit"
+        }
+      }
+    }
+  },
+
+  "forwardPorts": [3000, 8080, 1883],
+  "portsAttributes": {
+    "3000": {
+      "label": "MQTT Explorer Server",
+      "onAutoForward": "notify"
+    },
+    "8080": {
+      "label": "Webpack Dev Server",
+      "onAutoForward": "notify"
+    },
+    "1883": {
+      "label": "MQTT Broker",
+      "onAutoForward": "ignore"
+    }
+  },
+
+  "postCreateCommand": "yarn install",
+
+  "remoteUser": "node"
+}

.devcontainer/docker-compose.yml

@@ -0,0 +1,21 @@
+version: '3.8'
+
+services:
+  app:
+    image: mcr.microsoft.com/devcontainers/javascript-node:20
+    volumes:
+      - ../..:/workspace:cached
+    command: sleep infinity
+    network_mode: service:mosquitto
+    environment:
+      - MQTT_EXPLORER_USERNAME=dev
+      - MQTT_EXPLORER_PASSWORD=dev123
+
+  mosquitto:
+    image: eclipse-mosquitto:2
+    ports:
+      - "1883:1883"
+      - "3000:3000"
+      - "8080:8080"
+    volumes:
+      - ./mosquitto.conf:/mosquitto/config/mosquitto.conf:ro

.devcontainer/mosquitto.conf

@@ -0,0 +1,4 @@
+# Mosquitto configuration for development
+listener 1883
+allow_anonymous true
+persistence false

.github/copilot-instructions.md

@@ -0,0 +1,383 @@
+# GitHub Copilot Agent Instructions for MQTT Explorer
+
+## Overview
+
+MQTT Explorer is an Electron-based desktop application for exploring MQTT brokers. It provides a comprehensive UI for connecting to MQTT brokers, browsing topics, and analyzing message flows.
+
+## Technology Stack
+
+- **Frontend**: React 16.x with Material-UI
+- **Backend**: Node.js with TypeScript
+- **Desktop Framework**: Electron 29.x
+- **MQTT Client**: [mqttjs](https://github.com/mqttjs/MQTT.js) v4.x
+- **State Management**: Redux with redux-thunk
+- **Build Tools**: webpack, TypeScript compiler
+- **Testing**: Mocha + Chai for unit tests, Playwright for MCP introspection tests
+
+## Project Setup
+
+### Building and Running
+
+```bash
+# Install dependencies
+yarn install
+
+# Build the project
+yarn build
+
+# Set password for browser testing
+export MQTT_EXPLORER_USERNAME=admin
+export MQTT_EXPLORER_PASSWORD=secretpassword
+
+# Start the application
+yarn start
+
+# Start in development mode
+yarn dev
+```
+
+### Running with MCP Introspection (for testing)
+
+```bash
+# Build first
+yarn build
+
+# Start with MCP introspection enabled
+electron . --enable-mcp-introspection
+
+# Or with custom port
+electron . --enable-mcp-introspection --remote-debugging-port=9223
+```
+
+## Writing Tests
+
+### Requirements for All Tests
+
+1. **Tests MUST be deterministic** - They should produce the same results every time they run
+2. **Tests MUST be independent** - Each test should be able to run in isolation without depending on other tests
+3. **Include screenshots** - Visual verification is required for UI changes
+4. **Handle asynchronous operations properly** - This is an MQTT message queue tool
+
+### Best Practices for UI Tests
+
+#### 1. Use Given-When-Then Pattern
+Structure tests with clear Given-When-Then comments to make them readable:
+
+```typescript
+it('Given a JSON message sent to topic foo/bar/baz, the tree should display nested topics', async function () {
+  // Given: Mock MQTT publishes JSON to foo/bar/baz
+  // When: We wait for the topic to appear in the tree
+  // Then: Topic hierarchy should be visible (foo -> bar -> baz)
+})
+```
+
+#### 2. Wait for Elements, Don't Use Fixed Delays
+Prefer `waitFor` over `sleep` whenever possible:
+
+```typescript
+// ✓ Good: Wait for specific element
+const topic = await page.locator('span[data-test-topic="kitchen"]')
+await topic.waitFor({ state: 'visible', timeout: 5000 })
+
+// ✗ Bad: Fixed delay without verification
+await sleep(5000)
+```
+
+#### 3. Use Meaningful Assertions
+Every test should have explicit assertions that verify the expected state:
+
+```typescript
+// ✓ Good: Explicit assertion with meaningful message
+const treeNodes = await page.locator('[class*="TreeNode"]')
+const count = await treeNodes.count()
+expect(count).to.be.greaterThan(0, 'Topic tree should contain nodes')
+
+// ✗ Bad: No assertion, only screenshot
+await page.screenshot({ path: 'test.png' })
+```
+
+#### 4. Test Data-Driven Scenarios
+Write tests that describe the data flow:
+
+```typescript
+it('Given messages sent to livingroom/lamp/state and livingroom/lamp/brightness, both should appear under livingroom/lamp', async function () {
+  // Test implementation verifies the specific data flow
+})
+```
+
+#### 5. Use Data Test Attributes
+Leverage `data-test-*` attributes for reliable selectors:
+
+```typescript
+// ✓ Good: Use data-test attributes
+const topic = await page.locator('span[data-test-topic="kitchen"]')
+
+// ⚠ Acceptable: Use role/text when data attributes aren't available
+const button = await page.locator('//button/span[contains(text(),"Connect")]')
+
+// ✗ Bad: Rely on CSS classes that may change
+const topic = await page.locator('.MuiTreeItem-label')
+```
+
+#### 6. Verify Multiple Aspects
+Test should verify both state and UI:
+
+```typescript
+// Verify the action completed
+const isVisible = await disconnectButton.isVisible()
+expect(isVisible).to.be.true
+
+// Capture screenshot for visual verification
+await page.screenshot({ path: 'test-screenshot-connection.png' })
+```
+
+#### 7. Handle MQTT Asynchronous Nature
+Account for message propagation time:
+
+```typescript
+// Publish message
+await mockClient.publish('topic/name', 'value')
+
+// Wait for UI to update
+await page.locator(`text="value"`).waitFor({ timeout: 5000 })
+
+// Verify state
+const value = await page.textContent('.message-value')
+expect(value).toBe('value')
+```
+
+### Handling MQTT Asynchronous Operations
+
+MQTT is inherently asynchronous. When writing tests:
+
+- **Wait for message propagation**: Use proper wait strategies (e.g., `await page.waitForSelector()`, `await sleep()`)
+- **Don't assume immediate updates**: Messages take time to send, receive, and update the UI
+- **Use event-based waiting**: Wait for specific UI elements or state changes rather than fixed timeouts when possible
+- **Account for network latency**: MQTT broker communication involves network round trips
+
+### Example Test Pattern
+
+```typescript
+// 1. Perform action (e.g., publish message)
+await publishMessage(topic, payload)
+
+// 2. Wait for UI to update (not just arbitrary sleep)
+await page.waitForSelector(`text="${expectedValue}"`, { timeout: 5000 })
+
+// 3. Verify state
+const value = await page.textContent('.message-value')
+expect(value).toBe(expectedValue)
+
+// 4. Take screenshot for verification
+await page.screenshot({ path: 'test-result.png' })
+```
+
+### Running Tests
+
+```bash
+# Run all tests
+yarn test
+
+# Run specific test suites
+yarn test:app
+yarn test:backend
+yarn test:mcp
+
+# Run linters
+yarn lint
+yarn lint:fix
+```
+
+### Running UI Tests (yarn test:ui)
+
+The UI tests require specific setup in the test environment:
+
+**Prerequisites:**
+1. **Xvfb (X Virtual Framebuffer)** - Required for headless Electron testing
+   ```bash
+   # Start Xvfb on display :99
+   Xvfb :99 -screen 0 1024x720x24 -ac &
+   export DISPLAY=:99
+   ```
+
+2. **Mosquitto MQTT Broker** - Required for MQTT message testing
+   ```bash
+   # Install mosquitto
+   sudo apt-get install -y mosquitto mosquitto-clients
+   
+   # Start mosquitto service
+   sudo systemctl start mosquitto
+   
+   # Verify it's running on port 1883
+   sudo systemctl status mosquitto
+   ```
+
+3. **@types/node** - Required for TypeScript compilation
+   ```bash
+   yarn add -D @types/node
+   ```
+
+**Running UI Tests:**
+```bash
+# Build the application first
+yarn build
+
+# Run UI tests with proper display
+DISPLAY=:99 yarn test:ui
+```
+
+**Common Issues:**
+- **"Timeout exceeded" in before hook**: Mosquitto is not running or not accessible on port 1883
+- **"Cannot find type definition file for 'node'"**: Run `yarn add -D @types/node`
+- **Electron fails to launch**: Xvfb is not running or DISPLAY variable not set
+- **Tests hang**: Check if old Electron/mosquitto processes are still running and kill them
+
+**Environment Cleanup:**
+```bash
+# Kill old Electron processes
+ps aux | grep electron | grep -v grep | awk '{print $2}' | xargs kill -9 2>/dev/null
+
+# Kill old mosquitto processes (if running custom instance)
+ps aux | grep mosquitto | grep -v grep | awk '{print $2}' | xargs kill -9 2>/dev/null
+```
+
+## MCP Introspection Testing
+
+The project supports MCP (Model Context Protocol) for automated testing with Playwright:
+
+- Use `yarn test:mcp` to run automated UI tests
+- Tests launch the app with remote debugging enabled on port 9222
+- Connect to `http://localhost:9222` via Chrome DevTools Protocol
+
+## Project Structure
+
+- `app/` - Frontend React application
+- `backend/` - Backend models, tests, and connection management
+- `src/` - Electron main process and bindings
+- `src/spec/` - Test specifications including MCP introspection tests
+
+## Code Style and Formatting
+
+### Linting
+
+The project uses TSLint with Airbnb config and Prettier for code formatting:
+
+```bash
+# Run all linters
+yarn lint
+
+# Run linters individually
+yarn lint:prettier    # Check Prettier formatting
+yarn lint:tslint      # Check TSLint rules
+yarn lint:spellcheck  # Check spelling in code
+
+# Auto-fix issues
+yarn lint:fix         # Fix TSLint and Prettier issues
+yarn lint:tslint:fix  # Fix TSLint issues only
+yarn lint:prettier:fix # Fix Prettier issues only
+```
+
+### Code Style Rules
+
+- **Semicolons**: Never use semicolons (enforced by TSLint and Prettier)
+- **Quotes**: Single quotes for strings
+- **Indentation**: 2 spaces
+- **Line length**: Maximum 120 characters (Prettier) / 200 characters (TSLint)
+- **Arrow functions**: No parentheses for single parameters (`x => x + 1`)
+- **Trailing commas**: Required for multiline objects and arrays (ES5 compatible)
+
+### TypeScript Guidelines
+
+- Enable strict null checks and no implicit any
+- Use TypeScript interfaces for data structures
+- Prefer `const` over `let`, avoid `var`
+- Use type inference when possible, explicit types when clarity is needed
+
+## Dependency Management
+
+### Adding Dependencies
+
+```bash
+# Add to root project
+yarn add <package-name>
+
+# Add to app (frontend)
+cd app && yarn add <package-name>
+
+# Add to backend
+cd backend && yarn add <package-name>
+
+# Add dev dependencies
+yarn add -D <package-name>
+```
+
+### Important Dependency Notes
+
+- Main dependencies are in the root `package.json`
+- Frontend React app has its own dependencies in `app/package.json`
+- Backend models and logic have dependencies in `backend/package.json`
+- Always use `--frozen-lockfile` in CI to ensure reproducible builds
+- Run `yarn install` after pulling changes that modify `yarn.lock`
+
+## Debugging
+
+### Development Mode
+
+```bash
+# Start with hot reload for frontend
+yarn dev
+
+# This runs two processes in parallel:
+# 1. webpack-dev-server for the React app (port varies)
+# 2. Electron in development mode with the --development flag
+```
+
+### Debugging TypeScript
+
+- Source maps are enabled in `tsconfig.json`
+- Use `ts-node` for running TypeScript files directly
+- Backend tests can be debugged with: `cd backend && yarn test-inspect`
+
+### Common Issues
+
+- **Build fails**: Clear `dist/` and `app/build/` directories, then rebuild
+- **Electron won't start**: Ensure `yarn build` completed successfully
+- **Tests fail**: Check if MQTT broker (mosquitto) is running for integration tests
+- **UI not updating**: In dev mode, ensure webpack-dev-server is running
+
+## Deployment and Packaging
+
+### Creating Releases
+
+```bash
+# Prepare release (updates version, changelog)
+yarn prepare-release
+
+# Package the application for distribution
+yarn package
+
+# Package with Docker (for consistent builds)
+yarn package-with-docker
+```
+
+### Release Workflow
+
+- **Beta releases**: Create PR to `beta` branch with "feat:" or "fix:" commits
+- **Production releases**: Create PR to `release` branch with "feat:" or "fix:" commits
+- Semantic release automatically handles versioning and changelog
+- Builds are created for Windows, macOS, and Linux
+
+### Build Artifacts
+
+- Output directory: `build/`
+- Supported formats: DMG (macOS), EXE/NSIS (Windows), AppImage/Snap (Linux), AppX (Windows Store)
+- Code signing is configured via `res/` directory certificates and provisioning profiles
+
+## Important Notes
+
+- Always run `yarn build` before starting the application
+- The app uses Electron (see `package.json` for version)
+- MQTT communication is handled via [mqttjs](https://github.com/mqttjs/MQTT.js)
+- All code changes should pass linting (`yarn lint`)
+- Node.js version requirement: >= 20
+- The project uses workspace-like structure with separate package.json files for app and backend

.github/workflows/copilot-setup.yml

@@ -0,0 +1,39 @@
+name: Copilot Agent Setup
+
+on:
+  workflow_call:
+
+jobs:
+  setup:
+    runs-on: ubuntu-latest
+    
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+      
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+      
+      - name: Get yarn cache directory path
+        id: yarn-cache-dir-path
+        run: echo "dir=$(yarn cache dir)" >> $GITHUB_OUTPUT
+      
+      - name: Cache yarn dependencies
+        uses: actions/cache@v4
+        id: yarn-cache
+        with:
+          path: |
+            ${{ steps.yarn-cache-dir-path.outputs.dir }}
+            node_modules
+            app/node_modules
+          key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-yarn-
+      
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile
+      
+      - name: Build project
+        run: yarn build

.github/workflows/tests.yml

@@ -12,13 +12,58 @@ jobs:
       options: --user root
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
       - name: Install Packages
         run: yarn install --frozen-lockfile
       - name: Build
         run: yarn build
       - name: Test
         run: yarn test
-      - name: UI-Test
+
+  ui-tests:
+    runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/thomasnordquist/mqtt-explorer-ui-tests:latest
+      volumes:
+        - ./:/app
+      options: --user root
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+      - name: Install Packages
+        run: yarn install --frozen-lockfile
+      - name: Build
+        run: yarn build
+      - name: Run UI Tests
+        timeout-minutes: 10
+        run: ./scripts/runUiTests.sh
+      - name: Upload Test Screenshots
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: ui-test-screenshots
+          path: |
+            test-screenshot-*.png
+          retention-days: 30
+
+  demo-video:
+    runs-on: ubuntu-latest
+    container:
+      image: ghcr.io/thomasnordquist/mqtt-explorer-ui-tests:latest
+      volumes:
+        - ./:/app
+      options: --user root
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+      - name: Install Packages
+        run: yarn install --frozen-lockfile
+      - name: Build
+        run: yarn build
+      - name: Generate Demo Video
         run: yarn ui-test
       - name: Post-processing
         run: ./scripts/prepareVideo.sh
@@ -35,4 +80,56 @@ jobs:
       - name: Show URL
         run: echo '${{ steps.upload.outputs.file-url }}'
         id: artifact-upload-step
-      - run: echo '![test](${{ steps.upload.outputs.file-url }})' >> $GITHUB_STEP_SUMMARY
+      - run: echo '<picture><img src="${{ steps.upload.outputs.file-url }}"></picture>' >> $GITHUB_STEP_SUMMARY
+
+  test-browser:
+    runs-on: ubuntu-latest
+    services:
+      mosquitto:
+        image: eclipse-mosquitto:2
+        ports:
+          - 1883:1883
+        options: >-
+          --health-cmd "mosquitto_sub -t '$SYS/#' -C 1"
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+      - name: Install Dependencies
+        run: yarn install --frozen-lockfile
+      - name: Build Browser Mode
+        run: yarn build:server
+      - name: Test App
+        run: yarn test:app
+      - name: Test Backend
+        run: yarn test:backend
+      - name: Start Server in Background
+        run: |
+          yarn start:server &
+          echo $! > server.pid
+        env:
+          MQTT_EXPLORER_USERNAME: test
+          MQTT_EXPLORER_PASSWORD: test123
+          PORT: 3000
+      - name: Wait for Server
+        run: |
+          timeout 30 bash -c 'until curl -f http://localhost:3000; do sleep 1; done'
+      - name: Browser Smoke Test
+        run: |
+          # Test server is running
+          curl -f http://localhost:3000 || exit 1
+          echo "Browser mode server is running successfully"
+      - name: Stop Server
+        if: always()
+        run: |
+          if [ -f server.pid ]; then
+            kill $(cat server.pid) || true
+            rm server.pid
+          fi

.gitignore

@@ -9,3 +9,11 @@ test.png
 .awcache
 .scannerwork
 screen*.png
+
+# MCP introspection artifacts
+mqtt-explorer-mcp-screenshot.png
+screenshot-mcp-*.png
+test-mcp-introspection.js
+
+/data
+test-screenshot-*.png

BROWSER_MODE.md

@@ -0,0 +1,193 @@
+# Browser Mode Documentation
+
+MQTT Explorer now supports running as a web application served by a Node.js server, in addition to the existing Electron desktop app.
+
+## Running in Browser Mode
+
+### Quick Start
+
+1. Build the application for browser mode:
+   ```bash
+   yarn build:server
+   ```
+
+2. Start the server:
+   ```bash
+   yarn start:server
+   ```
+
+3. Open your browser and navigate to `http://localhost:3000`
+
+4. You'll be prompted to log in with credentials that were generated on server startup.
+
+### Development Mode
+
+To run in development mode with hot reload:
+
+```bash
+yarn dev:server
+```
+
+This starts both the webpack dev server and the backend server.
+
+## Authentication
+
+### Environment Variables
+
+You can set custom authentication credentials using environment variables:
+
+```bash
+export MQTT_EXPLORER_USERNAME=admin
+export MQTT_EXPLORER_PASSWORD=secretpassword
+yarn start:server
+```
+
+### Generated Credentials
+
+If no environment variables are set, the server will generate credentials on first startup and save them to `data/credentials.json`. The generated credentials will be printed to the console:
+
+```
+============================================================
+Generated new credentials:
+Username: user-abc123
+Password: 123e4567-e89b-12d3-a456-426614174000
+============================================================
+Please save these credentials. They will be persisted to:
+/path/to/data/credentials.json
+============================================================
+```
+
+## Features
+
+### Certificate Upload
+
+In browser mode, certificate files are uploaded directly through the browser using the HTML5 File API. The certificates are:
+- Read client-side as base64
+- Stored in the connection configuration
+- Used when establishing MQTT connections
+
+### Data Storage
+
+In browser mode, all data is stored on the server:
+- Credentials: `data/credentials.json`
+- Uploaded certificates: `data/certificates/`
+- File uploads: `data/uploads/`
+
+### Port Configuration
+
+The default port is 3000. You can change it using the `PORT` environment variable:
+
+```bash
+PORT=8080 yarn start:server
+```
+
+## Architecture
+
+### Client-Server Communication
+
+- **Electron Mode**: Uses Electron IPC for communication between renderer and main process
+- **Browser Mode**: Uses Socket.io WebSockets for real-time communication between browser and server
+
+The application automatically detects the environment and uses the appropriate transport layer.
+
+### Event Bus Abstraction
+
+Both Electron IPC and Socket.io implement the same `EventBusInterface`, allowing the application code to work seamlessly in both modes without modification.
+
+## Differences from Electron Mode
+
+### Browser Mode Limitations
+
+1. **File System Access**: Limited to server-side operations
+2. **Native Dialogs**: File selection uses browser file input instead of native dialogs
+3. **Auto-Updates**: Not available in browser mode
+4. **Tray Icon**: Not available in browser mode
+
+### Browser Mode Advantages
+
+1. **No Installation**: Access from any browser
+2. **Cross-Platform**: Works on any device with a modern browser
+3. **Remote Access**: Can be deployed on a server for remote access
+4. **Multi-User**: Can support authentication for multiple users
+
+## Security Considerations
+
+1. **HTTPS**: For production, always use HTTPS to encrypt credentials and MQTT data
+2. **Authentication**: Keep credentials secure and rotate them regularly
+3. **Network**: Ensure the server is on a trusted network or behind a firewall
+4. **Environment Variables**: Use environment variables for production credentials, not the generated ones
+
+## Deployment
+
+For production deployment:
+
+1. Build the application:
+   ```bash
+   yarn build:server
+   ```
+
+2. Set environment variables:
+   ```bash
+   export MQTT_EXPLORER_USERNAME=your_username
+   export MQTT_EXPLORER_PASSWORD=your_secure_password
+   export PORT=3000
+   ```
+
+3. Start the server:
+   ```bash
+   yarn start:server
+   ```
+
+4. Use a reverse proxy (nginx, Apache) to add HTTPS and additional security features
+
+## Troubleshooting
+
+### Debugging
+
+Enable detailed Socket.IO connection and lifecycle debugging:
+
+```bash
+DEBUG=mqtt-explorer:socketio* yarn start:server
+```
+
+Available debug namespaces:
+- `mqtt-explorer:socketio` - General Socket.IO events and metrics
+- `mqtt-explorer:socketio:connect` - Client connection events
+- `mqtt-explorer:socketio:disconnect` - Client disconnection and cleanup
+- `mqtt-explorer:socketio:subscriptions` - Subscription lifecycle tracking
+- `mqtt-explorer:socketio:connections` - MQTT connection ownership
+
+This will log:
+- Client connect/disconnect events
+- Subscription counts per socket
+- MQTT connection ownership tracking
+- Memory leak detection metrics (subscriptions, handlers, connections)
+
+Example output:
+```
+mqtt-explorer:socketio:connect Client connected: abc123de
+mqtt-explorer:socketio [connect] clients=1 subscriptions=8 mqttConns=0 | socket[abc123de]: subs=8 conns=0
+mqtt-explorer:socketio:connections Connection my-mqtt owned by socket abc123de (total: 1)
+mqtt-explorer:socketio:disconnect Client disconnected: abc123de
+mqtt-explorer:socketio:subscriptions Removed 8 subscriptions for socket abc123de
+mqtt-explorer:socketio [disconnect] clients=0 subscriptions=0 mqttConns=0 | socket[abc123de]: subs=0 conns=0
+```
+
+### Authentication Fails
+
+1. Check the console output for the generated credentials
+2. Clear browser session storage: `sessionStorage.clear()` in browser console
+3. Restart the server to regenerate credentials
+
+### Connection Issues
+
+1. Check that the server is running: `http://localhost:3000`
+2. Check browser console for Socket.io connection errors
+3. Verify firewall rules allow the port
+
+### Certificate Upload Issues
+
+In browser mode, certificates are handled differently:
+- Use the file upload button to select certificate files
+- Files are read and encoded client-side
+- Large certificate files (>16KB) will be rejected

CI_CD.md

@@ -0,0 +1,149 @@
+# CI/CD Pipeline Documentation
+
+## Overview
+
+MQTT Explorer uses GitHub Actions for continuous integration and testing. The pipeline tests both Electron (desktop) and browser modes.
+
+## Workflows
+
+### Test Workflow (`.github/workflows/tests.yml`)
+
+This workflow runs on pull requests to `master`, `beta`, and `release` branches.
+
+#### Jobs
+
+##### 1. `test` - Electron Mode Tests
+
+Tests the traditional Electron desktop application:
+
+- **Environment**: Custom Docker container (`ghcr.io/thomasnordquist/mqtt-explorer-ui-tests:latest`)
+- **Steps**:
+  1. Install dependencies with frozen lockfile
+  2. Build the Electron application
+  3. Run unit tests (app + backend)
+  4. Run UI tests with video recording
+  5. Upload test video to S3
+  6. Display test results in GitHub summary
+
+**Artifacts**: UI test video (GIF format) uploaded to S3
+
+##### 2. `test-browser` - Browser Mode Tests
+
+Tests the new browser/server mode:
+
+- **Environment**: Ubuntu latest with Node.js 20
+- **Services**:
+  - **Mosquitto MQTT Broker**: Eclipse Mosquitto v2 on port 1883
+    - Health checks enabled
+    - Anonymous connections allowed
+- **Steps**:
+  1. Setup Node.js 20
+  2. Install dependencies
+  3. Build browser mode (`yarn build:server`)
+  4. Run unit tests (app + backend)
+  5. Start server in background with test credentials
+  6. Wait for server to be ready
+  7. Run browser smoke tests
+  8. Clean up server process
+
+**Environment Variables**:
+- `MQTT_EXPLORER_USERNAME=test`
+- `MQTT_EXPLORER_PASSWORD=test123`
+- `PORT=3000`
+
+## Test Commands
+
+The following npm scripts are used in CI/CD:
+
+```bash
+# Unit tests
+yarn test              # Run all tests (app + backend)
+yarn test:app          # Frontend tests only
+yarn test:backend      # Backend tests only
+
+# Build
+yarn build             # Build Electron mode
+yarn build:server      # Build browser mode
+
+# UI Tests (Electron only)
+yarn ui-test           # Run UI tests with video recording
+```
+
+## Adding New Tests
+
+### For Electron Mode
+
+Add tests to the `test` job. UI tests should be added to the test suite that `yarn ui-test` runs.
+
+### For Browser Mode
+
+Browser-specific tests should:
+1. Use the pre-configured Mosquitto service
+2. Connect to `mqtt://mosquitto:1883`
+3. Test server endpoints at `http://localhost:3000`
+
+Example:
+```yaml
+- name: Browser Integration Test
+  run: |
+    # Test MQTT connection through server
+    curl -X POST http://localhost:3000/api/test
+```
+
+## Local Testing
+
+### Electron Mode
+
+```bash
+yarn build
+yarn test
+yarn ui-test
+```
+
+### Browser Mode
+
+```bash
+# Start Mosquitto in Docker
+docker run -d -p 1883:1883 eclipse-mosquitto:2
+
+# Build and test
+yarn build:server
+yarn test
+
+# Start server
+MQTT_EXPLORER_USERNAME=test MQTT_EXPLORER_PASSWORD=test123 yarn start:server
+
+# Run manual tests
+curl http://localhost:3000
+```
+
+## GitHub Codespaces / Devcontainer
+
+The repository includes a devcontainer configuration that automatically sets up:
+- Node.js 20
+- MQTT broker (Mosquitto)
+- All development dependencies
+- Port forwarding for development
+
+See [.devcontainer/README.md](.devcontainer/README.md) for details.
+
+## Troubleshooting
+
+### Browser Tests Failing
+
+1. **Server won't start**: Check if port 3000 is already in use
+2. **MQTT connection fails**: Ensure Mosquitto service is healthy
+3. **Timeout errors**: Increase timeout in "Wait for Server" step
+
+### Electron Tests Failing
+
+1. **UI tests timeout**: Check if the Docker container has display access
+2. **Build fails**: Verify all dependencies are in yarn.lock
+
+## Future Improvements
+
+- [ ] Add E2E browser tests with Playwright
+- [ ] Test WebSocket connections in browser mode
+- [ ] Add performance benchmarks
+- [ ] Test with different MQTT broker versions
+- [ ] Add security scanning for browser mode

LICENSE.md

@@ -1,10 +1,10 @@
-## creative commons
+When redistributing, the attribution page may not be altered or made less accessible without explicit approval.
 
-# Attribution-NoDerivatives 4.0 International
+# Creative Commons Attribution-ShareAlike 4.0 International
 
 Creative Commons Corporation (“Creative Commons”) is not a law firm and does not provide legal services or legal advice. Distribution of Creative Commons public licenses does not create a lawyer-client or other relationship. Creative Commons makes its licenses and related information available on an “as-is” basis. Creative Commons gives no warranties regarding its licenses, any material licensed under their terms and conditions, or any related information. Creative Commons disclaims all liability for damages resulting from their use to the fullest extent possible.
 
-### Using Creative Commons Public Licenses
+**Using Creative Commons Public Licenses**
 
 Creative Commons public licenses provide a standard set of terms and conditions that creators and other rights holders may use to share original works of authorship and other material subject to copyright and certain other rights specified in the public license below. The following considerations are for informational purposes only, are not exhaustive, and do not form part of our licenses.
 
@@ -12,31 +12,37 @@ Creative Commons public licenses provide a standard set of terms and conditions
 
 * __Considerations for the public:__ By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor’s permission is not necessary for any reason–for example, because of any applicable exception or limitation to copyright–then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. [More considerations for the public](http://wiki.creativecommons.org/Considerations_for_licensors_and_licensees#Considerations_for_licensees).
 
-## Creative Commons Attribution-NoDerivatives 4.0 International Public License
+## Creative Commons Attribution-ShareAlike 4.0 International Public License
 
-By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NoDerivatives 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.
+By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-ShareAlike 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.
 
 ### Section 1 – Definitions.
 
 a. __Adapted Material__ means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.
 
-b. __Copyright and Similar Rights__ means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.
+b. __Adapter's License__ means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.
 
-c. __Effective Technological Measures__ means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.
+c. __BY-SA Compatible License__ means a license listed at [creativecommons.org/compatiblelicenses](http://creativecommons.org/compatiblelicenses), approved by Creative Commons as essentially the equivalent of this Public License.
 
-d. __Exceptions and Limitations__ means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.
+d. __Copyright and Similar Rights__ means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.
 
-e. __Licensed Material__ means the artistic or literary work, database, or other material to which the Licensor applied this Public License.
+e. __Effective Technological Measures__ means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.
 
-f. __Licensed Rights__ means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.
+f. __Exceptions and Limitations__ means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.
 
-g. __Licensor__ means the individual(s) or entity(ies) granting rights under this Public License.
+g. __License Elements__ means the license attributes listed in the name of a Creative Commons Public License. The License Elements of this Public License are Attribution and ShareAlike.
 
-h. __Share__ means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.
+h. __Licensed Material__ means the artistic or literary work, database, or other material to which the Licensor applied this Public License.
 
-i. __Sui Generis Database Rights__ means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.
+i. __Licensed Rights__ means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.
 
-j. __You__ means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.
+j. __Licensor__ means the individual(s) or entity(ies) granting rights under this Public License.
+
+k. __Share__ means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.
+
+l. __Sui Generis Database Rights__ means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.
+
+m. __You__ means the individual or entity exercising the Licensed Rights under this Public License. __Your__ has a corresponding meaning.
 
 ### Section 2 – Scope.
 
@@ -46,7 +52,7 @@ a. ___License grant.___
 
        A. reproduce and Share the Licensed Material, in whole or in part; and
 
-       B. produce and reproduce, but not Share, Adapted Material.
+       B. produce, reproduce, and Share Adapted Material.
 
    2. __Exceptions and Limitations.__ For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.
 
@@ -58,7 +64,9 @@ a. ___License grant.___
 
        A. __Offer from the Licensor – Licensed Material.__ Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.
 
-       B. __No downstream restrictions.__ You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.
+       B. __Additional offer from the Licensor – Adapted Material.__ Every recipient of Adapted Material from You automatically receives an offer from the Licensor to exercise the Licensed Rights in the Adapted Material under the conditions of the Adapter’s License You apply.
+
+       C. __No downstream restrictions.__ You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.
 
    6. __No endorsement.__ Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).
 
@@ -76,7 +84,7 @@ Your exercise of the Licensed Rights is expressly made subject to the following
 
 a. ___Attribution.___
 
-   1. If You Share the Licensed Material, You must:
+   1. If You Share the Licensed Material (including in modified form), You must:
 
        A. retain the following if it is supplied by the Licensor with the Licensed Material:
 
@@ -94,19 +102,27 @@ a. ___Attribution.___
 
        C. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.
 
-       For the avoidance of doubt, You do not have permission under this Public License to Share Adapted Material.
-
    2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.
 
    3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.
 
+b. ___ShareAlike.___
+
+In addition to the conditions in Section 3(a), if You Share Adapted Material You produce, the following conditions also apply.
+
+1. The Adapter’s License You apply must be a Creative Commons license with the same License Elements, this version or later, or a BY-SA Compatible License.
+
+2. You must include the text of, or the URI or hyperlink to, the Adapter's License You apply. You may satisfy this condition in any reasonable manner based on the medium, means, and context in which You Share Adapted Material.
+
+3. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, Adapted Material that restrict exercise of the rights granted under the Adapter's License You apply.
+
 ### Section 4 – Sui Generis Database Rights.
 
 Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:
 
-a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database, provided You do not Share Adapted Material;
+a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database;
 
-b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and
+b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material, including for purposes of Section 3(b); and
 
 c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.
 
@@ -152,7 +168,6 @@ c. No term or condition of this Public License will be waived and no failure to
 
 d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.
 
-> Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at [creativecommons.org/policies](http://creativecommons.org/policies), Creative Commons does not authorize the use of the trademark “Creative Commons” or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.
+> Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the [CC0 Public Domain Dedication](https://creativecommons.org/publicdomain/zero/1.0/legalcode). Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at [creativecommons.org/policies](http://creativecommons.org/policies), Creative Commons does not authorize the use of the trademark “Creative Commons” or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.
 >
-> Creative Commons may be contacted at creativecommons.org
-
+> Creative Commons may be contacted at creativecommons.org.

Readme.md

@@ -18,8 +18,22 @@ Downloads can be found at the link above.
 This page is dedicated to its development.
 Pull-Requests and error reports are welcome.
 
+## Quick Start with GitHub Codespaces
+
+The fastest way to start developing is with GitHub Codespaces:
+
+1. Click the green "Code" button above
+2. Select "Codespaces" tab
+3. Click "Create codespace on [branch]"
+4. Wait for the environment to set up (includes Node.js and MQTT broker)
+5. Run `yarn dev:server` to start development
+
+The devcontainer includes a pre-configured MQTT broker and all development tools. See [.devcontainer/README.md](.devcontainer/README.md) for details.
+
 ## Run from sources
 
+### Desktop Application (Electron)
+
 ```bash
 npm install -g yarn
 yarn
@@ -27,8 +41,23 @@ yarn build
 yarn start
 ```
 
+### Browser Mode (Web Application)
+
+MQTT Explorer can also run as a web application served by a Node.js server:
+
+```bash
+npm install -g yarn
+yarn
+yarn build:server
+yarn start:server
+```
+
+Then open your browser to `http://localhost:3000`. For more details, see [BROWSER_MODE.md](BROWSER_MODE.md).
+
 ## Develop
 
+### Desktop Application
+
 Launch Application
 
 ```bash
@@ -37,32 +66,49 @@ yarn
 yarn dev
 ```
 
+### Browser Mode
+
+Launch in development mode with hot reload:
+
+```bash
+npm install -g yarn
+yarn
+yarn dev:server
+```
+
 The `app` directory contains all the rendering logic, the `backend` directory currently contains the models, tests, connection management, `src` contains all the electron bindings. [mqttjs](https://github.com/mqttjs/MQTT.js) is used to facilitate communication to MQTT brokers.
 
 ## Automated Tests
 
-To achieve a reliable product automated tests run regularly on travis.
+To achieve a reliable product automated tests run regularly on CI.
 
-- Data model
-- MQTT integration
-- UI-Tests (The demo is a recorded ui test)
+- **Data model tests**: `yarn test:backend`
+- **App tests**: `yarn test:app`
+- **UI test suite**: `yarn test:ui` (independent, deterministic tests)
+- **Demo video**: `yarn ui-test` (UI test recording for documentation)
 
-## Run UI-tests
+### Run UI Test Suite
 
-A [mosquitto](https://mosquitto.org/) MQTT broker is required to run the ui-tests.
-
-Run tests with
+The UI test suite validates core functionality through automated browser tests. Each test is independent and deterministic.
 
 ```bash
-# Run chromedriver in a separate terminal session
-./node_modules/.bin/chromedriver --url-base=wd/hub --port=9515 --verbose
+# Run with automated setup (recommended)
+./scripts/runUiTests.sh
+
+# Or run directly (requires manual MQTT broker setup)
+yarn build
+yarn test:ui
 ```
 
-Compile and execute tests
+See [docs/UI-TEST-SUITE.md](docs/UI-TEST-SUITE.md) for more details.
+
+### Run Demo Video Generation
+
+A [mosquitto](https://mosquitto.org/) MQTT broker is required to generate the demo video.
 
 ```bash
-npm run build
-node dist/src/spec/webdriverio.js
+yarn build
+yarn ui-test
 ```
 
 ## Create a release
@@ -99,7 +145,7 @@ The readme will be generated from the docs.
 
 ## License
 
-![CC-BY-ND 4.0](https://img.shields.io/badge/License-CC%20BY--ND%204.0-blue.svg)  
-[CC-BY-ND 4.0](https://creativecommons.org/licenses/by-nd/4.0/)
+![CC-BY-Nc 4.0](https://img.shields.io/badge/License-CC%20BY--NC%204.0-blue.svg)  
+[CC-BY-Nc 4.0](https://creativecommons.org/licenses/by-nC/4.0/)
 
-The license is a little restrictive to distributing derived work, this may change in the future if the interest arises or more people work on this project.
+The license allows for anyone to adapt, share, and redistribute the material, as long as it is non-commercial.

app/package.json

@@ -10,7 +10,7 @@
     "mochatest": "mocha --require ts-node/register --require source-map-support/register --recursive src/*/**/*.spec.ts"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=20"
   },
   "author": "",
   "license": "CC-BY-ND-4.0",
@@ -28,6 +28,7 @@
     "d3-shape": "^1.3.5",
     "diff": "^4.0.1",
     "dot-prop": "^5.0.0",
+    "events": "^3.3.0",
     "get-value": "^3.0.1",
     "immutable": "^4.0.0-rc.12",
     "in-viewport": "^3.6.0",
@@ -37,7 +38,9 @@
     "lodash.throttle": "^4.1.1",
     "moving-average": "^1.0.0",
     "number-abbreviate": "^2.0.0",
+    "os-browserify": "^0.3.0",
     "parse-duration": "^0.1.1",
+    "path-browserify": "^1.0.1",
     "prismjs": "^1.15.0",
     "react": "^16.11",
     "react-ace": "^8",
@@ -51,7 +54,8 @@
     "redux-batched-actions": "0.5",
     "redux-thunk": "^2.3.0",
     "sha1": "^1.1.1",
-    "socket.io-client": "^2.2.0",
+    "socket.io-client": "^4.8.1",
+    "url": "^0.11.4",
     "uuid": "7"
   },
   "devDependencies": {
@@ -66,7 +70,7 @@
     "@types/react-redux": "^7.0.9",
     "@types/react-resize-detector": "^4.0.1",
     "@types/sha1": "^1.1.1",
-    "@types/socket.io-client": "^1.4.32",
+    "@types/socket.io-client": "^3.0.0",
     "@types/uuid": "^7.0.2",
     "@types/vis": "^4.21.9",
     "chai": "^4.2.0",
@@ -80,14 +84,14 @@
     "node-loader": "^0.6.0",
     "source-map-loader": "^0.2.4",
     "style-loader": "^1",
-    "ts-loader": "^9.2.6",
+    "ts-loader": "^9.5.1",
     "typescript": "^4.5.5",
-    "webpack": "^5.69.1",
+    "webpack": "^5.91.0",
     "webpack-bundle-analyzer": "^4.5.0",
-    "webpack-cli": "^4.9.2",
-    "webpack-dev-server": "^4.7.4"
+    "webpack-cli": "^5.1.4",
+    "webpack-dev-server": "^5.0.4"
   },
   "peerDependencies": {
-    "electron": "^29"
+    "electron": "^39"
   }
-}
+}

app/src/actions/ConnectionManager.ts

@@ -9,12 +9,11 @@ import {
 import { default as persistentStorage, StorageIdentifier } from '../utils/PersistentStorage'
 import { Dispatch } from 'redux'
 import { showError } from './Global'
-import { promises as fsPromise } from 'fs'
 import * as path from 'path'
 import { ActionTypes, Action } from '../reducers/ConnectionManager'
 import { Subscription } from '../../../backend/src/DataSource/MqttSource'
 import { connectionsMigrator } from './migrations/Connection'
-import { rendererRpc } from '../../../events'
+import { rendererRpc, readFromFile } from '../../../events'
 import { makeOpenDialogRpc } from '../../../events/OpenDialogRequest'
 
 export interface ConnectionDictionary {
@@ -81,7 +80,7 @@ async function openCertificate(): Promise<CertificateParameters> {
     throw rejectReasons.noCertificateSelected
   }
 
-  const data = await fsPromise.readFile(selectedFile)
+  const data = await rendererRpc.call(readFromFile, { filePath: selectedFile })
   if (data.length > 16_384 || data.length < 64) {
     throw rejectReasons.certificateSizeDoesNotMatch
   }

app/src/actions/Publish.ts

@@ -2,7 +2,10 @@ import { Action, ActionTypes } from '../reducers/Publish'
 import { AppState } from '../reducers'
 import { Base64Message } from '../../../backend/src/Model/Base64Message'
 import { Dispatch } from 'redux'
-import { makePublishEvent, rendererEvents } from '../../../events'
+import { MqttMessage, makePublishEvent, rendererEvents, rendererRpc, readFromFile } from '../../../events'
+import { makeOpenDialogRpc } from '../../../events/OpenDialogRequest'
+import { showError } from './Global'
+import { Base64 } from 'js-base64'
 
 export const setTopic = (topic?: string): Action => {
   return {
@@ -11,6 +14,50 @@ export const setTopic = (topic?: string): Action => {
   }
 }
 
+export const openFile =
+  (encoding: 'utf8' = 'utf8') =>
+  async (dispatch: Dispatch<any>, getState: () => AppState) => {
+    try {
+      const file = await getFileContent(encoding)
+      if (file) {
+        dispatch(setPayload(file.data))
+      }
+    } catch (error) {
+      dispatch(showError(error))
+    }
+  }
+
+type FileParameters = {
+  name: string
+  data: string
+}
+async function getFileContent(encoding: string): Promise<FileParameters | undefined> {
+  const rejectReasons = {
+    noFileSelected: 'No file selected',
+    errorReadingFile: 'Error reading file',
+  }
+
+  const { canceled, filePaths } = await rendererRpc.call(makeOpenDialogRpc(), {
+    properties: ['openFile'],
+    securityScopedBookmarks: true,
+  })
+
+  if (canceled) {
+    return
+  }
+
+  const selectedFile = filePaths[0]
+  if (!selectedFile) {
+    throw rejectReasons.noFileSelected
+  }
+  try {
+    const data = await rendererRpc.call(readFromFile, { filePath: selectedFile, encoding })
+    return { name: selectedFile, data: data.toString(encoding) }
+  } catch (error) {
+    throw rejectReasons.errorReadingFile
+  }
+}
+
 export const setPayload = (payload?: string): Action => {
   return {
     payload,
@@ -41,7 +88,7 @@ export const publish = (connectionId: string) => (dispatch: Dispatch<Action>, ge
   }
 
   const publishEvent = makePublishEvent(connectionId)
-  const mqttMessage = {
+  const mqttMessage: Partial<MqttMessage> = {
     topic,
     payload: state.publish.payload ? Base64Message.fromString(state.publish.payload) : null,
     retain: state.publish.retain,

app/src/actions/Settings.ts

@@ -1,5 +1,5 @@
 import * as q from '../../../backend/src/Model'
-import { ActionTypes, SettingsStateModel, TopicOrder } from '../reducers/Settings'
+import { ActionTypes, SettingsStateModel, TopicOrder, ValueRendererDisplayMode } from '../reducers/Settings'
 import { AppState } from '../reducers'
 import { autoExpandLimitSet } from '../components/SettingsDrawer/Settings'
 import { Base64Message } from '../../../backend/src/Model/Base64Message'
@@ -68,13 +68,14 @@ export const selectTopicWithMouseOver = (doSelect: boolean) => (dispatch: Dispat
   dispatch(storeSettings())
 }
 
-export const setValueDisplayMode = (valueRendererDisplayMode: 'diff' | 'raw') => (dispatch: Dispatch<any>) => {
-  dispatch({
-    valueRendererDisplayMode,
-    type: ActionTypes.SETTINGS_SET_VALUE_RENDERER_DISPLAY_MODE,
-  })
-  dispatch(storeSettings())
-}
+export const setValueDisplayMode =
+  (valueRendererDisplayMode: ValueRendererDisplayMode) => (dispatch: Dispatch<any>) => {
+    dispatch({
+      valueRendererDisplayMode,
+      type: ActionTypes.SETTINGS_SET_VALUE_RENDERER_DISPLAY_MODE,
+    })
+    dispatch(storeSettings())
+  }
 
 export const toggleHighlightTopicUpdates = () => (dispatch: Dispatch<any>) => {
   dispatch({
@@ -117,7 +118,7 @@ export const filterTopics = (filterStr: string) => (dispatch: Dispatch<any>, get
     const messageMatches =
       node.message &&
       node.message.payload &&
-      Base64Message.toUnicodeString(node.message.payload).toLowerCase().indexOf(filterStr) !== -1
+      node.message.payload.toUnicodeString().toLowerCase().indexOf(filterStr) !== -1
 
     return Boolean(messageMatches)
   }

app/src/actions/Tree.ts

@@ -33,13 +33,8 @@ const debouncedSelectTopic = debounce(
       setTopicDispatch = setTopic(topic.path())
     }
 
-    if (previouslySelectedTopic && previouslySelectedTopic.viewModel) {
-      previouslySelectedTopic.viewModel.setSelected(false)
-    }
-
-    if (topic.viewModel) {
-      topic.viewModel.setSelected(true)
-    }
+    previouslySelectedTopic?.viewModel?.setSelected(false)
+    topic.viewModel?.setSelected(true)
 
     const selectTreeTopicDispatch = {
       selectedTopic: topic,

app/src/components/BrowserAuthWrapper.tsx

@@ -0,0 +1,64 @@
+import * as React from 'react'
+import { LoginDialog } from './LoginDialog'
+
+interface BrowserAuthWrapperProps {
+  children: React.ReactNode
+}
+
+const isBrowserMode =
+  typeof window !== 'undefined' && (typeof process === 'undefined' || process.env?.BROWSER_MODE === 'true')
+
+export function BrowserAuthWrapper(props: BrowserAuthWrapperProps) {
+  const [isAuthenticated, setIsAuthenticated] = React.useState(false)
+  const [loginError, setLoginError] = React.useState<string | undefined>()
+  const [showLogin, setShowLogin] = React.useState(false)
+
+  React.useEffect(() => {
+    if (!isBrowserMode) {
+      // Not in browser mode, skip authentication
+      setIsAuthenticated(true)
+      return
+    }
+
+    // Check if already authenticated
+    const username = sessionStorage.getItem('mqtt-explorer-username')
+    const password = sessionStorage.getItem('mqtt-explorer-password')
+
+    if (username && password) {
+      // Try to use stored credentials
+      setIsAuthenticated(true)
+    } else {
+      // Show login dialog
+      setShowLogin(true)
+    }
+  }, [])
+
+  const handleLogin = async (username: string, password: string) => {
+    try {
+      // Store credentials in session storage
+      sessionStorage.setItem('mqtt-explorer-username', username)
+      sessionStorage.setItem('mqtt-explorer-password', password)
+
+      // The socket will use these credentials on next connection
+      setIsAuthenticated(true)
+      setShowLogin(false)
+      setLoginError(undefined)
+
+      // Reload to reinitialize socket with new auth
+      window.location.reload()
+    } catch (error) {
+      setLoginError('Login failed. Please check your credentials.')
+    }
+  }
+
+  if (!isBrowserMode) {
+    // Not in browser mode, render children directly
+    return <>{props.children}</>
+  }
+
+  if (!isAuthenticated) {
+    return <LoginDialog open={showLogin} onLogin={handleLogin} error={loginError} />
+  }
+
+  return <>{props.children}</>
+}

app/src/components/ChartPanel/TopicChart.tsx

@@ -114,6 +114,7 @@ function TopicChart(props: Props) {
         </div>
       </div>
       <TopicPlot
+        node={props.treeNode ? props.treeNode : undefined}
         color={props.parameters.color}
         interpolation={props.parameters.interpolation}
         timeInterval={props.parameters.timeRange ? props.parameters.timeRange.until : undefined}

app/src/components/ConnectionSetup/BrowserCertificateFileSelection.tsx

@@ -0,0 +1,140 @@
+import * as React from 'react'
+import ClearAdornment from '../helper/ClearAdornment'
+import Lock from '@material-ui/icons/Lock'
+import { bindActionCreators } from 'redux'
+import { Button, Theme, Tooltip, Typography } from '@material-ui/core'
+import { CertificateParameters, ConnectionOptions } from '../../model/ConnectionOptions'
+import { CertificateTypes } from '../../actions/ConnectionManager'
+import { connect } from 'react-redux'
+import { connectionManagerActions } from '../../actions'
+import { withStyles } from '@material-ui/styles'
+import { rendererRpc } from '../../../../events'
+import { RpcEvents } from '../../../../events/EventsV2'
+
+function BrowserCertificateFileSelection(props: {
+  certificateType: CertificateTypes
+  title: string
+  certificate?: CertificateParameters
+  classes: any
+  actions: {
+    connectionManager: typeof connectionManagerActions
+  }
+  connection: ConnectionOptions
+}) {
+  const fileInputRef = React.useRef<HTMLInputElement>(null)
+
+  const clearCertificate = React.useCallback(() => {
+    props.actions.connectionManager.updateConnection(props.connection.id, {
+      [props.certificateType]: undefined,
+    })
+  }, [props.connection, props.certificateType])
+
+  const handleFileSelect = React.useCallback(
+    async (event: React.ChangeEvent<HTMLInputElement>) => {
+      const file = event.target.files?.[0]
+      if (!file) {
+        return
+      }
+
+      try {
+        // Read file content
+        const reader = new FileReader()
+        reader.onload = async e => {
+          const content = e.target?.result
+          if (typeof content === 'string') {
+            // Convert to base64
+            const base64Data = content.split(',')[1] || content
+
+            // Upload via IPC instead of HTTP POST
+            const result = await rendererRpc.call(RpcEvents.uploadCertificate, {
+              filename: file.name,
+              data: base64Data,
+            })
+
+            // Create certificate parameters
+            const certificate: CertificateParameters = {
+              name: result.name,
+              data: result.data,
+            }
+
+            // Update connection
+            props.actions.connectionManager.updateConnection(props.connection.id, {
+              [props.certificateType]: certificate,
+            })
+          }
+        }
+        reader.readAsDataURL(file)
+      } catch (error) {
+        console.error('Error uploading certificate:', error)
+      }
+
+      // Reset input
+      if (fileInputRef.current) {
+        fileInputRef.current.value = ''
+      }
+    },
+    [props.connection.id, props.certificateType, props.actions.connectionManager]
+  )
+
+  const handleButtonClick = () => {
+    fileInputRef.current?.click()
+  }
+
+  return (
+    <span>
+      <input
+        ref={fileInputRef}
+        type="file"
+        accept=".pem,.crt,.cer,.key"
+        style={{ display: 'none' }}
+        onChange={handleFileSelect}
+      />
+      <Tooltip title="Select certificate" placement="top">
+        <Button variant="contained" className={props.classes.button} onClick={handleButtonClick}>
+          <Lock /> {props.title}
+        </Button>
+      </Tooltip>
+      <ClearCertificate classes={props.classes} certificate={props.certificate} action={clearCertificate} />
+    </span>
+  )
+}
+
+function ClearCertificate(props: { classes: any; certificate?: CertificateParameters; action: () => void }) {
+  if (!props.certificate) {
+    return null
+  }
+
+  return (
+    <Tooltip title={props.certificate.name}>
+      <Typography className={props.classes.certificateName}>
+        <ClearAdornment action={props.action} value={props.certificate.name} />
+        {props.certificate.name}
+      </Typography>
+    </Tooltip>
+  )
+}
+
+const mapDispatchToProps = (dispatch: any) => {
+  return {
+    actions: {
+      connectionManager: bindActionCreators(connectionManagerActions, dispatch),
+    },
+  }
+}
+
+const styles = (theme: Theme) => ({
+  certificateName: {
+    width: '100%',
+    height: 'calc(1em + 4px)',
+    overflow: 'hidden' as 'hidden',
+    whiteSpace: 'nowrap' as 'nowrap',
+    textOverflow: 'ellipsis' as 'ellipsis',
+    color: theme.palette.text.hint,
+  },
+  button: {
+    marginTop: theme.spacing(3),
+    marginRight: theme.spacing(2),
+  },
+})
+
+export default connect(undefined, mapDispatchToProps)(withStyles(styles)(BrowserCertificateFileSelection))

app/src/components/ConnectionSetup/Certificates.tsx

@@ -1,5 +1,6 @@
 import * as React from 'react'
 import CertificateFileSelection from './CertificateFileSelection'
+import BrowserCertificateFileSelection from './BrowserCertificateFileSelection'
 import Undo from '@material-ui/icons/Undo'
 import { bindActionCreators } from 'redux'
 import { Button, Grid } from '@material-ui/core'
@@ -8,6 +9,11 @@ import { connectionManagerActions } from '../../actions'
 import { ConnectionOptions } from '../../model/ConnectionOptions'
 import { Theme, withStyles } from '@material-ui/core/styles'
 
+// Check if we're in browser mode
+const isBrowserMode =
+  typeof window !== 'undefined' && (typeof process === 'undefined' || process.env?.BROWSER_MODE === 'true')
+const CertSelector = isBrowserMode ? BrowserCertificateFileSelection : CertificateFileSelection
+
 interface Props {
   connection: ConnectionOptions
   classes: any
@@ -45,7 +51,7 @@ class Certificates extends React.PureComponent<Props, State> {
         <form noValidate={true} autoComplete="off">
           <Grid container={true} spacing={3}>
             <Grid item={true} xs={12} className={classes.gridPadding}>
-              <CertificateFileSelection
+              <CertSelector
                 connection={this.props.connection}
                 certificate={this.props.connection.selfSignedCertificate}
                 title="Server Certificate (CA)"
@@ -53,7 +59,7 @@ class Certificates extends React.PureComponent<Props, State> {
               />
             </Grid>
             <Grid item={true} xs={12} className={classes.gridPadding}>
-              <CertificateFileSelection
+              <CertSelector
                 connection={this.props.connection}
                 certificate={this.props.connection.clientCertificate}
                 title="Client Certificate"
@@ -61,7 +67,7 @@ class Certificates extends React.PureComponent<Props, State> {
               />
             </Grid>
             <Grid item={true} xs={12} className={classes.gridPadding}>
-              <CertificateFileSelection
+              <CertSelector
                 connection={this.props.connection}
                 certificate={this.props.connection.clientKey}
                 title="Client Key"

app/src/components/ConnectionSetup/ProfileList/ConnectionItem.tsx

@@ -1,26 +1,40 @@
-import React from 'react'
+import React, { useCallback } from 'react'
 import { connect } from 'react-redux'
 import { ListItem, Typography } from '@material-ui/core'
 import { toMqttConnection, ConnectionOptions } from '../../../model/ConnectionOptions'
 import { withStyles, Theme } from '@material-ui/core/styles'
 import { bindActionCreators } from 'redux'
-import { connectionManagerActions } from '../../../actions'
+import { connectionActions, connectionManagerActions } from '../../../actions'
 
 export interface Props {
   connection: ConnectionOptions
-  actions: any
+  actions: {
+    connection: any
+    connectionManager: any
+  }
   selected: boolean
   classes: any
 }
 
 const ConnectionItem = (props: Props) => {
+  const connect = useCallback(() => {
+    const mqttOptions = toMqttConnection(props.connection)
+    if (mqttOptions) {
+      props.actions.connection.connect(mqttOptions, props.connection.id)
+    }
+  }, [props.connection, props])
+
   const connection = props.connection.host && toMqttConnection(props.connection)
   return (
     <ListItem
       button={true}
       selected={props.selected}
       style={{ display: 'block' }}
-      onClick={() => props.actions.selectConnection(props.connection.id)}
+      onClick={() => props.actions.connectionManager.selectConnection(props.connection.id)}
+      onDoubleClick={() => {
+        props.actions.connectionManager.selectConnection(props.connection.id)
+        connect()
+      }}
     >
       <Typography className={props.classes.name}>{props.connection.name || 'mqtt broker'}</Typography>
       <Typography className={props.classes.details}>{connection && connection.url}</Typography>
@@ -30,10 +44,12 @@ const ConnectionItem = (props: Props) => {
 
 export const mapDispatchToProps = (dispatch: any) => {
   return {
-    actions: bindActionCreators(connectionManagerActions, dispatch),
+    actions: {
+      connection: bindActionCreators(connectionActions, dispatch),
+      connectionManager: bindActionCreators(connectionManagerActions, dispatch),
+    },
   }
 }
-
 export const connectionItemStyle = (theme: Theme) => ({
   name: {
     width: '100%',

app/src/components/ConnectionSetup/ProfileList/index.tsx

@@ -7,7 +7,7 @@ import { connect } from 'react-redux'
 import { connectionManagerActions } from '../../../actions'
 import { ConnectionOptions } from '../../../model/ConnectionOptions'
 import { KeyCodes } from '../../../utils/KeyCodes'
-import { List, ListSubheader } from '@material-ui/core'
+import { List } from '@material-ui/core'
 import { Theme, withStyles } from '@material-ui/core/styles'
 import { useGlobalKeyEventHandler } from '../../../effects/useGlobalKeyEventHandler'
 

app/src/components/Demo/Mouse.tsx

@@ -6,40 +6,219 @@ interface State {
   enabled: boolean
   target: { x: number; y: number }
   position: { x: number; y: number }
-  stepSizeX: number
-  stepSizeY: number
+  startPosition: { x: number; y: number }
+  startTime: number
+  duration: number
+  clicking: boolean
+  jitterSeed: number
+  overshootTarget: { x: number; y: number } | null
+  isOvershootCorrection: boolean
 }
 
 class Demo extends React.Component<{ classes: any }, State> {
   private timer: any
+  private clickTimer: any
   private frameInterval = 20
+  private readonly correctionDelayMs = 50 // Delay before overshoot correction starts
 
   constructor(props: any) {
     super(props)
-    this.state = { enabled: false, target: { x: 0, y: 0 }, position: { x: 0, y: 0 }, stepSizeX: 1, stepSizeY: 1 }
+    this.state = {
+      enabled: false,
+      target: { x: 0, y: 0 },
+      position: { x: 0, y: 0 },
+      startPosition: { x: 0, y: 0 },
+      startTime: 0,
+      duration: 0,
+      clicking: false,
+      jitterSeed: Math.random(),
+      overshootTarget: null,
+      isOvershootCorrection: false,
+    }
   }
 
-  private moveCloser(steps: number = 0) {
-    const steSizeX = Math.min(this.state.stepSizeX, Math.abs(this.state.position.x - this.state.target.x))
-    const steSizeY = Math.min(this.state.stepSizeY, Math.abs(this.state.position.y - this.state.target.y))
-    const dirX = this.state.position.x > this.state.target.x ? -1 : 1
-    const dirY = this.state.position.y > this.state.target.y ? -1 : 1
+  /**
+   * Generates a seeded random value using a simple LCG algorithm
+   * Better quality than sin-based PRNG for consistent jitter patterns
+   */
+  private seededRandom(seed: number): number {
+    // Linear Congruential Generator with common constants
+    const a = 1664525
+    const c = 1013904223
+    const m = Math.pow(2, 32)
+    const x = (a * seed + c) % m
+    return x / m
+  }
 
-    if (steSizeX <= 0.1 && steSizeY <= 0.1) {
-      this.timer && clearTimeout(this.timer)
-      return
+  /**
+   * Adds human-like micro-movements to the cursor position
+   * Small random offsets that don't affect the overall path significantly
+   */
+  private addJitter(x: number, y: number, progress: number): { x: number; y: number } {
+    // Jitter is strongest in the middle of the movement (more natural)
+    const jitterStrength = Math.sin(progress * Math.PI) * 2 // 0 at start/end, max at middle
+
+    // Use progress to vary the seed for different jitter at each frame
+    const seed1 = this.state.jitterSeed * 1000 + progress * 100
+    const seed2 = this.state.jitterSeed * 2000 + progress * 150
+
+    const jitterX = (this.seededRandom(seed1) - 0.5) * jitterStrength
+    const jitterY = (this.seededRandom(seed2) - 0.5) * jitterStrength
+
+    return {
+      x: x + jitterX,
+      y: y + jitterY,
     }
+  }
+
+  /**
+   * Cubic bezier easing function for natural-looking mouse movement
+   * Uses control points (0.25, 0.75) for a smooth ease-in-out curve
+   */
+  private cubicBezier(t: number, p0: number, p1: number, p2: number, p3: number): number {
+    const u = 1 - t
+    return u * u * u * p0 + 3 * u * u * t * p1 + 3 * u * t * t * p2 + t * t * t * p3
+  }
+
+  /**
+   * Easing function that creates a smooth acceleration and deceleration
+   * This makes the mouse movement appear more human-like
+   */
+  private easeInOutCubic(t: number): number {
+    // Cubic bezier approximation for ease-in-out
+    return this.cubicBezier(t, 0, 0.25, 0.75, 1)
+  }
+
+  /**
+   * Calculates an overshoot target for more realistic human-like movement
+   * Returns null if no overshoot, or a point slightly past the target
+   */
+  private calculateOvershootTarget(
+    startX: number,
+    startY: number,
+    targetX: number,
+    targetY: number
+  ): { x: number; y: number } | null {
+    const dx = targetX - startX
+    const dy = targetY - startY
+    const distance = Math.sqrt(dx * dx + dy * dy)
+
+    // Don't overshoot for very short distances (less than 10px)
+    if (distance < 10) {
+      return null
+    }
+
+    // 30% chance of overshoot for natural variation
+    if (this.seededRandom(this.state.jitterSeed * 3) > 0.3) {
+      return null
+    }
+
+    // Overshoot by 2-8% of the distance
+    const overshootPercent = 0.02 + this.seededRandom(this.state.jitterSeed * 4) * 0.06
+    const overshootDistance = distance * overshootPercent
+
+    // Overshoot in the direction of movement
+    const dirX = dx / distance
+    const dirY = dy / distance
+
+    return {
+      x: targetX + dirX * overshootDistance,
+      y: targetY + dirY * overshootDistance,
+    }
+  }
+
+  private moveCloser() {
+    const elapsed = Date.now() - this.state.startTime
+    const progress = Math.min(elapsed / (this.state.duration || 1), 1)
+
+    // Apply easing function for smooth, human-like movement timing
+    const easedProgress = this.easeInOutCubic(progress)
+
+    // Determine actual target (could be overshoot target or final target)
+    const actualTarget = this.state.overshootTarget || this.state.target
+
+    // Calculate bezier curve control points for a natural arc trajectory
+    // Instead of moving in a straight line, the cursor follows a curved path
+    const startX = this.state.startPosition.x
+    const startY = this.state.startPosition.y
+    const endX = actualTarget.x
+    const endY = actualTarget.y
+
+    // Create control points for a quadratic bezier curve
+    // The control point is offset perpendicular to the direct line, creating an arc
+    const dx = endX - startX
+    const dy = endY - startY
+    const distance = Math.sqrt(dx * dx + dy * dy)
+
+    // Arc height is proportional to distance (80% of distance, capped at 200px max)
+    // Quadrupled from original 20% to make the curve highly visible
+    // For overshoot correction, use smaller arc (more direct)
+    const arcPercent = this.state.isOvershootCorrection ? 0.3 : 0.8
+    const arcCap = this.state.isOvershootCorrection ? 50 : 200
+    const arcHeight = Math.min(distance * arcPercent, arcCap)
+
+    // Calculate perpendicular offset for the control point
+    const perpX = -dy / (distance || 1)
+    const perpY = dx / (distance || 1)
+
+    // Add slight randomness to control point to avoid perfectly predictable curves
+    const controlPointJitter = this.seededRandom(this.state.jitterSeed * 5) * 20 - 10
+
+    // Control point is at the midpoint, offset perpendicular to create an arc
+    const controlX = (startX + endX) / 2 + perpX * (arcHeight + controlPointJitter)
+    const controlY = (startY + endY) / 2 + perpY * (arcHeight + controlPointJitter)
+
+    // Calculate position on quadratic bezier curve: B(t) = (1-t)²P₀ + 2(1-t)tP₁ + t²P₂
+    const t = easedProgress
+    const u = 1 - t
+    let newX = u * u * startX + 2 * u * t * controlX + t * t * endX
+    let newY = u * u * startY + 2 * u * t * controlY + t * t * endY
+
+    // Add jitter for human-like micro-movements
+    const jittered = this.addJitter(newX, newY, progress)
+    newX = jittered.x
+    newY = jittered.y
 
     this.setState({
       position: {
-        x: this.state.position.x + dirX * steSizeX,
-        y: this.state.position.y + dirY * steSizeY,
+        x: newX,
+        y: newY,
       },
     })
 
-    this.timer = setTimeout(() => {
-      this.moveCloser(steps + 1)
-    }, this.frameInterval)
+    // Continue animation if not complete
+    if (progress < 1) {
+      // Add random delay variation (jitter in timing)
+      // Frame interval varies between 15-25ms for irregular movement
+      // Use modulo to keep seed in reasonable range
+      const jitterDelay = this.seededRandom((this.state.jitterSeed * 6 + elapsed) % 100000) * 10 - 5
+      const nextInterval = Math.max(10, this.frameInterval + jitterDelay)
+
+      this.timer = setTimeout(() => {
+        this.moveCloser()
+      }, nextInterval)
+    } else {
+      this.timer && clearTimeout(this.timer)
+
+      // If we just reached overshoot target, start correction to actual target
+      if (this.state.overshootTarget && !this.state.isOvershootCorrection) {
+        const correctionDuration = this.state.duration * 0.15 // Correction takes 15% of original time
+        setTimeout(() => {
+          this.setState({
+            startPosition: { x: this.state.position.x, y: this.state.position.y },
+            target: this.state.target, // Keep original target
+            overshootTarget: null, // Clear overshoot
+            isOvershootCorrection: true,
+            startTime: Date.now(),
+            duration: correctionDuration,
+          })
+          this.moveCloser()
+        }, this.correctionDelayMs)
+      } else {
+        // Reset overshoot state for next movement
+        this.setState({ isOvershootCorrection: false })
+      }
+    }
   }
 
   public componentDidMount() {
@@ -47,11 +226,40 @@ class Demo extends React.Component<{ classes: any }, State> {
       this.setState({ enabled: true })
     }
     ;(window as any).demo.moveMouse = (x: number, y: number, animationTime: number) => {
-      const stepSizeX = Math.abs(this.state.position.x - x) / (animationTime / this.frameInterval)
-      const stepSizeY = Math.abs(this.state.position.y - y) / (animationTime / this.frameInterval)
-      this.setState({ stepSizeX, stepSizeY, enabled: true, target: { x, y } })
+      const newJitterSeed = Math.random()
+      const currentPos = this.state.position
+
+      // Calculate if this movement should have overshoot
+      const overshoot = this.calculateOvershootTarget(currentPos.x, currentPos.y, x, y)
+
+      // If overshoot exists, adjust duration to account for correction time
+      // Main movement gets 85% of time, correction gets 15%
+      const mainDuration = overshoot ? animationTime * 0.85 : animationTime
+
+      this.setState({
+        enabled: true,
+        target: { x, y }, // Store the actual target
+        overshootTarget: overshoot, // May be null or an overshoot position
+        isOvershootCorrection: false,
+        startPosition: { x: currentPos.x, y: currentPos.y },
+        startTime: Date.now(),
+        duration: mainDuration,
+        jitterSeed: newJitterSeed,
+      })
       this.moveCloser()
     }
+    ;(window as any).demo.clickMouse = () => {
+      this.setState({ clicking: true })
+      this.clickTimer && clearTimeout(this.clickTimer)
+      this.clickTimer = setTimeout(() => {
+        this.setState({ clicking: false })
+      }, 300)
+    }
+  }
+
+  public componentWillUnmount() {
+    this.timer && clearTimeout(this.timer)
+    this.clickTimer && clearTimeout(this.clickTimer)
   }
 
   public render() {
@@ -64,11 +272,26 @@ class Demo extends React.Component<{ classes: any }, State> {
       top: this.state.position.y + 2,
     }
 
-    return <img src={cursor} style={cursorStyle} className={this.props.classes.cursor} />
+    return (
+      <>
+        <img src={cursor} style={cursorStyle} className={this.props.classes.cursor} />
+        {this.state.clicking && <div style={cursorStyle} className={this.props.classes.clickRipple} />}
+      </>
+    )
   }
 }
 
 const style = (theme: Theme) => ({
+  '@keyframes clickPulse': {
+    from: {
+      transform: 'scale(1)',
+      opacity: 1,
+    },
+    to: {
+      transform: 'scale(2.5)',
+      opacity: 0,
+    },
+  },
   cursor: {
     width: '32px',
     height: '32px',
@@ -77,6 +300,16 @@ const style = (theme: Theme) => ({
     filter: theme.palette.type === 'light' ? undefined : 'invert(100%)',
     pointerEvents: 'none' as 'none',
   },
+  clickRipple: {
+    width: '48px',
+    height: '48px',
+    position: 'fixed' as 'fixed',
+    zIndex: 1000000 - 1, // Just below cursor
+    borderRadius: '50%',
+    border: '4px solid #4CAF50',
+    animation: '$clickPulse 300ms ease-out',
+    pointerEvents: 'none' as 'none',
+  },
 })
 
 export default withStyles(style)(Demo)

app/src/components/LoginDialog.tsx

@@ -0,0 +1,57 @@
+import * as React from 'react'
+import { Dialog, DialogTitle, DialogContent, DialogActions, TextField, Button, Typography } from '@material-ui/core'
+
+interface LoginDialogProps {
+  open: boolean
+  onLogin: (username: string, password: string) => void
+  error?: string
+}
+
+export function LoginDialog(props: LoginDialogProps) {
+  const [username, setUsername] = React.useState('')
+  const [password, setPassword] = React.useState('')
+
+  const handleSubmit = (e: React.FormEvent) => {
+    e.preventDefault()
+    props.onLogin(username, password)
+  }
+
+  return (
+    <Dialog open={props.open} disableEscapeKeyDown disableBackdropClick>
+      <form onSubmit={handleSubmit}>
+        <DialogTitle>Login to MQTT Explorer</DialogTitle>
+        <DialogContent>
+          {props.error && (
+            <Typography color="error" style={{ marginBottom: 16 }}>
+              {props.error}
+            </Typography>
+          )}
+          <TextField
+            autoFocus
+            margin="dense"
+            label="Username"
+            type="text"
+            fullWidth
+            value={username}
+            onChange={e => setUsername(e.target.value)}
+            required
+          />
+          <TextField
+            margin="dense"
+            label="Password"
+            type="password"
+            fullWidth
+            value={password}
+            onChange={e => setPassword(e.target.value)}
+            required
+          />
+        </DialogContent>
+        <DialogActions>
+          <Button type="submit" color="primary" variant="contained">
+            Login
+          </Button>
+        </DialogActions>
+      </form>
+    </Dialog>
+  )
+}

app/src/components/SettingsDrawer/BrokerStatistics.tsx

@@ -123,7 +123,7 @@ function renderStat(tree: q.Tree<TopicViewModel>, stat: Stats) {
     return null
   }
 
-  const str = node.message.payload ? Base64Message.toUnicodeString(node.message.payload) : ''
+  const str = node.message.payload ? node.message.payload.toUnicodeString() : ''
   let value = node.message && node.message.payload ? parseFloat(str) : NaN
   value = !isNaN(value) ? abbreviate(value) : str
 

app/src/components/Sidebar/CodeDiff/ChartPreview.tsx

@@ -69,7 +69,11 @@ function ChartPreview(props: Props) {
       <Popper open={open} anchorEl={chartIconRef.current} placement="left-end">
         <Fade in={open} timeout={300}>
           <Paper style={{ width: '300px' }}>
-            {open ? <TopicPlot history={props.treeNode.messageHistory} dotPath={props.literal.path} /> : <span />}
+            {open ? (
+              <TopicPlot node={props.treeNode} history={props.treeNode.messageHistory} dotPath={props.literal.path} />
+            ) : (
+              <span />
+            )}
           </Paper>
         </Fade>
       </Popper>

app/src/components/Sidebar/Publish/Publish.tsx

@@ -1,5 +1,5 @@
 import Editor from './Editor'
-import FormatAlignLeft from '@material-ui/icons/FormatAlignLeft'
+import { AttachFileOutlined, FormatAlignLeft } from '@material-ui/icons'
 import Message from './Model/Message'
 import Navigation from '@material-ui/icons/Navigation'
 import PublishHistory from './PublishHistory'
@@ -116,6 +116,10 @@ const EditorMode = memo(function EditorMode(props: {
     props.actions.setEditorMode(value)
   }, [])
 
+  const openFile = useCallback(() => {
+    props.actions.openFile()
+  }, [])
+
   const formatJson = useCallback(() => {
     if (props.payload) {
       try {
@@ -132,6 +136,7 @@ const EditorMode = memo(function EditorMode(props: {
       <div style={{ width: '100%', lineHeight: '64px', textAlign: 'center' }}>
         <EditorModeSelect value={props.editorMode} onChange={updateMode} focusEditor={props.focusEditor} />
         <FormatJsonButton editorMode={props.editorMode} focusEditor={props.focusEditor} formatJson={formatJson} />
+        <OpenFileButton editorMode={props.editorMode} openFile={openFile} />
         <div style={{ float: 'right' }}>
           <PublishButton publish={props.publish} focusEditor={props.focusEditor} />
         </div>
@@ -163,6 +168,20 @@ const FormatJsonButton = React.memo(function FormatJsonButton(props: {
   )
 })
 
+const OpenFileButton = React.memo(function OpenFileButton(props: { editorMode: string; openFile: () => void }) {
+  return (
+    <Tooltip title="Open file">
+      <Fab
+        style={{ width: '36px', height: '36px', margin: '0 8px' }}
+        onClick={props.openFile}
+        id="sidebar-publish-open-file"
+      >
+        <AttachFileOutlined style={{ fontSize: '20px' }} />
+      </Fab>
+    </Tooltip>
+  )
+})
+
 const PublishButton = memo(function PublishButton(props: { publish: () => void; focusEditor: () => void }) {
   const handleClickPublish = useCallback(
     (e: React.MouseEvent) => {

app/src/components/Sidebar/Sidebar.tsx

@@ -1,10 +1,9 @@
 import * as q from '../../../../backend/src/Model'
 import React, { useState, useEffect, useCallback } from 'react'
-import ExpandMore from '@material-ui/icons/ExpandMore'
 import NodeStats from './NodeStats'
 import ValuePanel from './ValueRenderer/ValuePanel'
 import { AppState } from '../../reducers'
-import { Badge, ExpansionPanel, ExpansionPanelDetails, ExpansionPanelSummary, Typography } from '@material-ui/core'
+import { ExpansionPanelDetails } from '@material-ui/core'
 import { bindActionCreators } from 'redux'
 import { connect } from 'react-redux'
 import { settingsActions, sidebarActions } from '../../actions'
@@ -28,7 +27,7 @@ interface Props {
 }
 
 function useUpdateNodeWhenNodeReceivesUpdates(node?: q.TreeNode<any>) {
-  const [lastUpdate, setLastUpdate] = useState(0)
+  const [, setLastUpdate] = useState(0)
   const updateNode = useCallback(
     throttle(() => {
       setLastUpdate(node ? node.lastUpdate : 0)
@@ -52,7 +51,6 @@ function Sidebar(props: Props) {
   const { classes, tree, nodePath } = props
   const node = usePollingToFetchTreeNode(tree, nodePath || '')
   useUpdateNodeWhenNodeReceivesUpdates(node)
-  // console.log(node && node.path(), tree, nodePath)
 
   return (
     <div id="Sidebar" className={classes.drawer}>

app/src/components/Sidebar/TopicPanel/TopicPanel.tsx

@@ -6,19 +6,19 @@ import Topic from './Topic'
 import { bindActionCreators } from 'redux'
 import { connect } from 'react-redux'
 import { RecursiveTopicDeleteButton } from './RecursiveTopicDeleteButton'
-import { sidebarActions } from '../../../actions'
 import { TopicDeleteButton } from './TopicDeleteButton'
+import { TopicTypeButton } from './TopicTypeButton'
+import { sidebarActions } from '../../../actions'
 
 const TopicPanel = (props: { node?: q.TreeNode<any>; actions: typeof sidebarActions }) => {
   const { node } = props
-  console.log(node && node.path())
+
   const copyTopic = node ? <Copy value={node.path()} /> : null
 
   const deleteTopic = useCallback((topic?: q.TreeNode<any>, recursive: boolean = false) => {
     if (!topic) {
       return
     }
-
     props.actions.clearTopic(topic, recursive)
   }, [])
 
@@ -29,11 +29,12 @@ const TopicPanel = (props: { node?: q.TreeNode<any>; actions: typeof sidebarActi
           Topic {copyTopic}
           <TopicDeleteButton node={node} deleteTopicAction={deleteTopic} />
           <RecursiveTopicDeleteButton node={node} deleteTopicAction={deleteTopic} />
+          <TopicTypeButton node={node} />
         </span>
         <Topic node={node} />
       </Panel>
     ),
-    [node, node && node.childTopicCount()]
+    [node, node?.childTopicCount()]
   )
 }
 

app/src/components/Sidebar/TopicPanel/TopicTypeButton.tsx

@@ -0,0 +1,103 @@
+import React, { useCallback, useMemo } from 'react'
+import * as q from '../../../../../backend/src/Model'
+import ClickAwayListener from '@material-ui/core/ClickAwayListener'
+import Grow from '@material-ui/core/Grow'
+import Button from '@material-ui/core/Button'
+import Paper from '@material-ui/core/Paper'
+import Popper from '@material-ui/core/Popper'
+import MenuItem from '@material-ui/core/MenuItem'
+import MenuList from '@material-ui/core/MenuList'
+import WarningRounded from '@material-ui/icons/WarningRounded'
+import { MessageDecoder, decoders } from '../../../decoders'
+import { Tooltip } from '@material-ui/core'
+
+export const TopicTypeButton = (props: { node?: q.TreeNode<any> }) => {
+  const { node } = props
+  if (!node || !node.message || !node.message.payload) {
+    return null
+  }
+
+  const options = decoders.flatMap(decoder => decoder.formats.map(format => [decoder, format] as const))
+
+  const [anchorEl, setAnchorEl] = React.useState<null | HTMLElement>(null)
+  const [open, setOpen] = React.useState(false)
+
+  const selectOption = useCallback(
+    (decoder: MessageDecoder, format: string) => {
+      if (!node) {
+        return
+      }
+
+      node.viewModel.decoder = { decoder, format }
+      setOpen(false)
+    },
+    [node]
+  )
+
+  const handleToggle = useCallback(
+    (event: React.MouseEvent<HTMLElement>) => {
+      event.stopPropagation()
+      if (open === true) {
+        return
+      }
+      setAnchorEl(event.currentTarget)
+      setOpen(prevOpen => !prevOpen)
+    },
+    [open]
+  )
+
+  const handleClose = useCallback((event: React.MouseEvent<Document, MouseEvent>) => {
+    if (anchorEl && anchorEl.contains(event.target as HTMLElement)) {
+      return
+    }
+    setOpen(false)
+  }, [])
+
+  return (
+    <Button onClick={handleToggle}>
+      {props.node?.viewModel.decoder?.format ?? props.node?.type}
+      <Popper open={open} anchorEl={anchorEl} role={undefined} transition>
+        {({ TransitionProps, placement }) => (
+          <Grow
+            {...TransitionProps}
+            style={{
+              transformOrigin: placement === 'bottom' ? 'center top' : 'center bottom',
+            }}
+          >
+            <Paper>
+              <ClickAwayListener onClickAway={handleClose}>
+                <MenuList id="topicTypeMode">
+                  {options.map(([decoder, format], index) => (
+                    <MenuItem
+                      key={format}
+                      selected={node && format === node.type}
+                      onClick={() => selectOption(decoder, format)}
+                    >
+                      <DecoderStatus decoder={decoder} format={format} node={node} />
+                    </MenuItem>
+                  ))}
+                </MenuList>
+              </ClickAwayListener>
+            </Paper>
+          </Grow>
+        )}
+      </Popper>
+    </Button>
+  )
+}
+
+function DecoderStatus({ node, decoder, format }: { node: q.TreeNode<any>; decoder: MessageDecoder; format: string }) {
+  const decoded = useMemo(() => {
+    return node.message?.payload && decoder.decode(node.message?.payload, format)
+  }, [node.message, decoder, format])
+
+  return decoded?.error ? (
+    <Tooltip title={decoded.error}>
+      <div>
+        {format} <WarningRounded />
+      </div>
+    </Tooltip>
+  ) : (
+    <>{format}</>
+  )
+}

app/src/components/Sidebar/ValueRenderer/MessageHistory.tsx

@@ -5,7 +5,6 @@ import Copy from '../../helper/Copy'
 import DateFormatter from '../../helper/DateFormatter'
 import History from '../HistoryDrawer'
 import TopicPlot from '../../TopicPlot'
-import { Base64Message } from '../../../../../backend/src/Model/Base64Message'
 import { isPlottable } from '../CodeDiff/util'
 import { TopicViewModel } from '../../../model/TopicViewModel'
 import { bindActionCreators } from 'redux'
@@ -13,6 +12,8 @@ import { chartActions } from '../../../actions'
 import { connect } from 'react-redux'
 import CustomIconButton from '../../helper/CustomIconButton'
 import { MessageId } from '../MessageId'
+import { useSubscription } from '../../hooks/useSubscription'
+import { useDecoder } from '../../hooks/useDecoder'
 
 const throttle = require('lodash.throttle')
 
@@ -25,117 +26,100 @@ interface Props {
   }
 }
 
-interface State {
-  displayMessage?: q.Message
-  anchorEl?: HTMLElement
-  lastUpdate: number
-}
+export const MessageHistory: React.FC<Props> = props => {
+  const [, setLastUpdate] = React.useState(Date.now())
+  const updateNodeThrottled = React.useCallback(
+    throttle(() => {
+      setLastUpdate
+    }, 300),
+    []
+  )
 
-class MessageHistory extends React.PureComponent<Props, State> {
-  private updateNode = throttle(() => {
-    this.setState({ lastUpdate: Date.now() })
-  }, 300)
+  useSubscription(props.node?.onMessage, updateNodeThrottled)
+  const decodeMessage = useDecoder(props.node)
 
-  constructor(props: any) {
-    super(props)
-    this.state = { lastUpdate: 0 }
-  }
-
-  private addNodeToCharts = (event: React.MouseEvent) => {
+  function addNodeToCharts(event: React.MouseEvent) {
     event.preventDefault()
     event.stopPropagation()
 
-    const { node } = this.props
+    const { node } = props
     if (!node) {
       return null
     }
 
-    this.props.actions.charts.addChart({ topic: node.path() })
+    props.actions.charts.addChart({ topic: node.path() })
   }
 
-  private displayMessage = (index: number, eventTarget: EventTarget) => {
-    const message = this.props.node && this.props.node.messageHistory.toArray().reverse()[index]
+  function displayMessage(index: number, eventTarget: EventTarget) {
+    const message = props.node && props.node.messageHistory.toArray().reverse()[index]
     if (message) {
-      this.props.onSelect(message)
+      props.onSelect(message)
     }
   }
 
-  public componentWillReceiveProps(nextProps: Props) {
-    this.props.node && this.props.node.onMessage.unsubscribe(this.updateNode)
-    nextProps.node && nextProps.node.onMessage.subscribe(this.updateNode)
+  const { node } = props
+  if (!node) {
+    return null
   }
 
-  public componentDidMount() {
-    this.props.node && this.props.node.onMessage.subscribe(this.updateNode)
-  }
+  const history = node.messageHistory.toArray()
+  let previousMessage: q.Message | undefined = node.message
+  const historyElements = [...history].reverse().map((message, idx) => {
+    const value = node.message ? decodeMessage(message)?.message?.format()[0] ?? null : null
 
-  public componentWillUnMount() {
-    this.props.node && this.props.node.onMessage.unsubscribe(this.updateNode)
-  }
-
-  public render() {
-    const { node } = this.props
-    if (!node) {
-      return null
-    }
-
-    const history = node.messageHistory.toArray()
-    let previousMessage: q.Message | undefined = node.message
-    const historyElements = [...history].reverse().map((message, idx) => {
-      const value = message.payload ? Base64Message.toUnicodeString(message.payload) : ''
-      const element = {
-        value,
-        key: `${message.messageNumber}-${message.received}`,
-        title: (
+    const element = {
+      value: value ?? '',
+      key: `${message.messageNumber}-${message.received}`,
+      title: (
+        <span>
+          <div style={{ float: 'left' }}>
+            <DateFormatter date={message.received} />
+            {previousMessage && previousMessage !== message ? (
+              <i>
+                (-
+                <DateFormatter date={message.received} intervalSince={previousMessage.received} />)
+              </i>
+            ) : null}
+          </div>
           <span>
-            <div style={{ float: 'left' }}>
-              <DateFormatter date={message.received} />
-              {previousMessage && previousMessage !== message ? (
-                <i>
-                  (-
-                  <DateFormatter date={message.received} intervalSince={previousMessage.received} />)
-                </i>
-              ) : null}
-            </div>
-            <span>
-              &nbsp;
-              <MessageId message={message} />
-            </span>
-            <div style={{ float: 'right' }}>
-              <Copy value={value} />
-            </div>
+            &nbsp;
+            <MessageId message={message} />
           </span>
-        ),
-        selected: message && message === this.props.selected,
-      }
-      previousMessage = message
-      return element
-    })
+          <div style={{ float: 'right' }}>
+            <Copy value={value ?? ''} />
+          </div>
+        </span>
+      ),
+      selected: message && message === props.selected,
+    }
+    previousMessage = message
+    return element
+  })
 
-    const isMessagePlottable =
-      node.message && node.message.payload && isPlottable(Base64Message.toUnicodeString(node.message.payload))
-    return (
-      <div>
-        <History
-          items={historyElements}
-          contentTypeIndicator={
-            isMessagePlottable ? (
-              <CustomIconButton
-                style={{ height: '22px', width: '22px' }}
-                onClick={this.addNodeToCharts}
-                tooltip="Add to chart panel"
-              >
-                <ShowChart style={{ marginTop: '-5px' }} />
-              </CustomIconButton>
-            ) : undefined
-          }
-          onClick={this.displayMessage}
-        >
-          {isMessagePlottable ? <TopicPlot history={node.messageHistory} /> : null}
-        </History>
-      </div>
-    )
-  }
+  const value = node.message ? decodeMessage(node.message)?.message?.format()[0] ?? null : null
+
+  const isMessagePlottable = isPlottable(value)
+  return (
+    <div>
+      <History
+        items={historyElements}
+        contentTypeIndicator={
+          isMessagePlottable ? (
+            <CustomIconButton
+              style={{ height: '22px', width: '22px' }}
+              onClick={addNodeToCharts}
+              tooltip="Add to chart panel"
+            >
+              <ShowChart style={{ marginTop: '-5px' }} />
+            </CustomIconButton>
+          ) : undefined
+        }
+        onClick={displayMessage}
+      >
+        {isMessagePlottable ? <TopicPlot node={node} history={node.messageHistory} /> : null}
+      </History>
+    </div>
+  )
 }
 
 const mapDispatchToProps = (dispatch: any) => {
@@ -144,4 +128,4 @@ const mapDispatchToProps = (dispatch: any) => {
   }
 }
 
-export default connect(null, mapDispatchToProps)(MessageHistory)
+export default connect(null, mapDispatchToProps)(React.memo(MessageHistory))

app/src/components/Sidebar/ValueRenderer/ValuePanel.tsx

@@ -1,19 +1,20 @@
 import * as q from '../../../../../backend/src/Model'
 import ActionButtons from './ActionButtons'
 import Copy from '../../helper/Copy'
+import Save from '../../helper/Save'
 import DateFormatter from '../../helper/DateFormatter'
 import MessageHistory from './MessageHistory'
 import Panel from '../Panel'
 import React, { useCallback } from 'react'
 import ValueRenderer from './ValueRenderer'
 import { AppState } from '../../../reducers'
-import { Base64Message } from '../../../../../backend/src/Model/Base64Message'
 import { bindActionCreators } from 'redux'
 import { Theme, Typography, withStyles } from '@material-ui/core'
 import { connect } from 'react-redux'
 import { sidebarActions } from '../../../actions'
 import DeleteSelectedTopicButton from './DeleteSelectedTopicButton'
 import { MessageId } from '../MessageId'
+import { useDecoder } from '../../hooks/useDecoder'
 
 interface Props {
   node?: q.TreeNode<any>
@@ -35,6 +36,7 @@ function RenderedValue(props: { node?: q.TreeNode<any>; compareMessage?: q.Messa
 
 function ValuePanel(props: Props) {
   const { node, compareMessage } = props
+  const decodeMessage = useDecoder(node)
 
   function renderViewOptions() {
     if (!props.node || !props.node.message) {
@@ -54,6 +56,16 @@ function ValuePanel(props: Props) {
     )
   }
 
+  const getDecodedValue = useCallback(() => {
+    return node?.message && decodeMessage(node.message)?.message?.toUnicodeString()
+  }, [node, decodeMessage])
+
+  const getData = () => {
+    if (node?.message && node.message.payload) {
+      return node.message.payload.base64Message
+    }
+  }
+
   function messageMetaInfo() {
     if (!props.node || !props.node.message) {
       return null
@@ -85,14 +97,16 @@ function ValuePanel(props: Props) {
     [compareMessage]
   )
 
-  const copyValue =
-    node && node.message && node.message.payload ? (
-      <Copy value={Base64Message.toUnicodeString(node.message.payload)} />
-    ) : null
+  const [value] =
+    node && node.message && node.message.payload ? node.message.payload?.format(node.type) : [null, undefined]
+  const copyValue = value ? <Copy getValue={getDecodedValue} /> : null
+  const saveValue = value ? <Save getData={getData} /> : null
 
   return (
     <Panel>
-      <span>Value {copyValue}</span>
+      <span>
+        Value {copyValue} {saveValue}
+      </span>
       <span style={{ width: '100%' }}>
         {renderViewOptions()}
         <div style={{ marginBottom: '-8px', marginTop: '8px' }}>

app/src/components/Sidebar/ValueRenderer/ValueRenderer.tsx

@@ -1,12 +1,13 @@
 import * as q from '../../../../../backend/src/Model'
-import * as React from 'react'
+import React, { useMemo } from 'react'
 import CodeDiff from '../CodeDiff'
 import { AppState } from '../../../reducers'
-import { Base64Message } from '../../../../../backend/src/Model/Base64Message'
 import { connect } from 'react-redux'
 import { ValueRendererDisplayMode } from '../../../reducers/Settings'
 import { Fade } from '@material-ui/core'
 import { Decoder } from '../../../../../backend/src/Model/Decoder'
+import { useDecoder } from '../../hooks/useDecoder'
+import { TopicViewModel } from '../../../model/TopicViewModel'
 
 interface Props {
   message: q.Message
@@ -15,103 +16,114 @@ interface Props {
   renderMode: ValueRendererDisplayMode
 }
 
-interface State {
-  width: number
+type Language = 'json'
+
+function renderDiff(
+  treeNode: q.TreeNode<TopicViewModel>,
+  compareWithPreviousMessage: boolean,
+  current: string = '',
+  previous: string = '',
+  title?: string,
+  language?: Language
+) {
+  return (
+    <CodeDiff
+      treeNode={treeNode}
+      previous={previous}
+      current={current}
+      title={title}
+      language={language}
+      nameOfCompareMessage={compareWithPreviousMessage ? 'selected' : 'previous'}
+    />
+  )
 }
 
-class ValueRenderer extends React.Component<Props, State> {
-  constructor(props: Props) {
-    super(props)
-    this.state = { width: 0 }
-  }
+function renderDiffMode(
+  treeNode: q.TreeNode<TopicViewModel>,
+  currentStr: string | undefined,
+  compareStr: string | undefined,
+  currentType: Language | undefined,
+  compareType: Language | undefined,
+  compareWithPreviousMessage: boolean
+) {
+  const language = currentType === compareType && compareType === 'json' ? 'json' : undefined
 
-  private renderDiff(current: string = '', previous: string = '', title?: string, language?: 'json') {
-    return (
-      <CodeDiff
-        treeNode={this.props.treeNode}
-        previous={previous}
-        current={current}
-        title={title}
-        language={language}
-        nameOfCompareMessage={this.props.compareWith ? 'selected' : 'previous'}
-      />
-    )
-  }
+  return <div>{renderDiff(treeNode, compareWithPreviousMessage, currentStr, compareStr, undefined, language)}</div>
+}
 
-  private convertMessage(msg?: Base64Message): [string | undefined, 'json' | undefined] {
-    if (!msg) {
-      return [undefined, undefined]
-    }
+function renderRawMode(
+  treeNode: q.TreeNode<TopicViewModel>,
+  currentStr: string | undefined,
+  compareStr: string | undefined,
+  currentType: Language | undefined,
+  compareType: Language | undefined,
+  compareWithPreviousMessage: boolean
+) {
+  return (
+    <div>
+      {renderDiff(treeNode, compareWithPreviousMessage, currentStr, currentStr, undefined, currentType)}
+      <Fade in={Boolean(compareStr)} timeout={400}>
+        <div>
+          {Boolean(compareStr)
+            ? renderDiff(treeNode, compareWithPreviousMessage, compareStr, compareStr, 'selected', compareType)
+            : null}
+        </div>
+      </Fade>
+    </div>
+  )
+}
 
-    const str = Base64Message.toUnicodeString(msg)
-    try {
-      JSON.parse(str)
-    } catch (error) {
-      return [str, undefined]
-    }
+export const ValueRenderer: React.FC<Props> = ({ treeNode, compareWith: compare, message, renderMode }) => {
+  const decodeMessage = useDecoder(treeNode)
+  const decodedMessage = useMemo(() => decodeMessage(message), [decodeMessage, message])
 
-    return [this.messageToPrettyJson(str), 'json']
-  }
+  const previousMessages = treeNode.messageHistory.toArray()
+  const previousMessage = previousMessages[previousMessages.length - 2]
+  const compareMessage = compare || previousMessage || message
+  const compareWithPreviousMessage = !!compare
 
-  private messageToPrettyJson(str: string): string | undefined {
-    try {
-      const json = JSON.parse(str)
-      return JSON.stringify(json, undefined, '  ')
-    } catch {
-      return undefined
-    }
-  }
+  const [currentStr, currentType] = useMemo(
+    () => decodedMessage?.message?.format(treeNode.type) ?? [],
+    [decodedMessage, treeNode.type]
+  )
+  const [compareStr, compareType] = useMemo(
+    () => decodeMessage(compareMessage)?.message?.format(treeNode.type) ?? [],
+    [compareMessage, decodeMessage, treeNode.type]
+  )
 
-  private renderRawMode(message: q.Message, compare?: q.Message) {
-    if (!message.payload) {
-      return
-    }
-    const [value, valueLanguage] = this.convertMessage(message.payload)
-    const [compareStr, compareStrLanguage] =
-      compare && compare.payload ? this.convertMessage(compare.payload) : [undefined, undefined]
-
-    return (
-      <div>
-        {this.renderDiff(value, value, undefined, valueLanguage)}
-        <Fade in={Boolean(compareStr)} timeout={400}>
-          <div>
-            {Boolean(compareStr) ? this.renderDiff(compareStr, compareStr, 'selected', compareStrLanguage) : null}
-          </div>
-        </Fade>
-      </div>
-    )
-  }
-
-  public render() {
-    return (
-      <div style={{ padding: '0px 0px 8px 0px', width: '100%' }}>
-        {this.props.message?.payload?.decoder === Decoder.SPARKPLUG && 'Decoded SparkplugB'}
-        {this.renderValue()}
-      </div>
-    )
-  }
-
-  public renderValue() {
-    const { message, treeNode, compareWith, renderMode } = this.props
-    const previousMessages = treeNode.messageHistory.toArray()
-    const previousMessage = previousMessages[previousMessages.length - 2]
-    const compareMessage = compareWith || previousMessage || message
-
-    if (renderMode === 'raw') {
-      return this.renderRawMode(message, compareWith)
-    }
-    if (!message.payload) {
+  function renderValue(
+    treeNode: q.TreeNode<TopicViewModel>,
+    currentStr: string | undefined,
+    compareStr: string | undefined,
+    currentType: Language | undefined,
+    compareType: Language | undefined,
+    renderMode: string,
+    compareWithPreviousMessage: boolean
+  ) {
+    if (!decodedMessage) {
       return null
     }
 
-    const compareValue = compareMessage.payload || message.payload
-    const [current, currentLanguage] = this.convertMessage(message.payload)
-    const [compare, compareLanguage] = this.convertMessage(compareValue)
-
-    const language = currentLanguage === compareLanguage && compareLanguage === 'json' ? 'json' : undefined
-
-    return this.renderDiff(current, compare, undefined, language)
+    switch (renderMode) {
+      case 'diff':
+        return renderDiffMode(treeNode, currentStr, compareStr, currentType, compareType, compareWithPreviousMessage)
+      default:
+        return renderRawMode(treeNode, currentStr, compareStr, currentType, compareType, compareWithPreviousMessage)
+    }
   }
+
+  const renderedValue = useMemo(
+    () =>
+      renderValue(treeNode, currentStr, compareStr, currentType, compareType, renderMode, compareWithPreviousMessage),
+    [treeNode, currentStr, compareStr, currentType, compareType, renderMode, compareWithPreviousMessage]
+  )
+
+  return (
+    <div style={{ padding: '0px 0px 8px 0px', width: '100%' }}>
+      {decodedMessage?.decoder === Decoder.SPARKPLUG && 'Decoded SparkplugB'}
+      {renderedValue}
+    </div>
+  )
 }
 
 const mapStateToProps = (state: AppState) => {

app/src/components/TopicPlot.tsx

@@ -2,12 +2,14 @@ import * as dotProp from 'dot-prop'
 import * as q from '../../../backend/src/Model'
 import * as React from 'react'
 import PlotHistory from './Chart/Chart'
-import { Base64Message } from '../../../backend/src/Model/Base64Message'
 import { toPlottableValue } from './Sidebar/CodeDiff/util'
 import { PlotCurveTypes } from '../reducers/Charts'
+import { DecoderFunction, useDecoder } from './hooks/useDecoder'
+
 const parseDuration = require('parse-duration')
 
 interface Props {
+  node?: q.TreeNode<any>
   history: q.MessageHistory
   dotPath?: string
   timeInterval?: string
@@ -25,21 +27,27 @@ function filterUsingTimeRange(startTime: number | undefined, data: Array<q.Messa
   return data
 }
 
-function nodeToHistory(startTime: number | undefined, history: q.MessageHistory) {
+function nodeToHistory(decodeMessage: DecoderFunction, startTime: number | undefined, history: q.MessageHistory) {
   return filterUsingTimeRange(startTime, history.toArray())
     .map((message: q.Message) => {
-      const value = message.payload ? toPlottableValue(Base64Message.toUnicodeString(message.payload)) : NaN
-      return { x: message.received.getTime(), y: toPlottableValue(value) }
+      const decoded = decodeMessage(message)?.message?.toUnicodeString()
+      return { x: message.received.getTime(), y: toPlottableValue(decoded) }
     })
     .filter(data => !isNaN(data.y as any)) as any
 }
 
-function nodeDotPathToHistory(startTime: number | undefined, history: q.MessageHistory, dotPath: string) {
+function nodeDotPathToHistory(
+  decodeMessage: DecoderFunction,
+  startTime: number | undefined,
+  history: q.MessageHistory,
+  dotPath: string
+) {
   return filterUsingTimeRange(startTime, history.toArray())
     .map((message: q.Message) => {
       let json: any = {}
       try {
-        json = message.payload ? JSON.parse(Base64Message.toUnicodeString(message.payload)) : {}
+        const decoded = decodeMessage(message)?.message
+        json = decoded ? JSON.parse(decoded.toUnicodeString()) : {}
       } catch (ignore) {}
 
       const value = dotProp.get(json, dotPath)
@@ -50,14 +58,17 @@ function nodeDotPathToHistory(startTime: number | undefined, history: q.MessageH
 }
 
 function TopicPlot(props: Props) {
+  const decodeMessage = useDecoder(props.node)
   const startOffset = props.timeInterval ? parseDuration(props.timeInterval) : undefined
-  const data = React.useMemo(
-    () =>
-      props.dotPath
-        ? nodeDotPathToHistory(startOffset, props.history, props.dotPath)
-        : nodeToHistory(startOffset, props.history),
-    [props.history.last(), startOffset, props.dotPath]
-  )
+  const data = React.useMemo(() => {
+    if (!props.node) {
+      return []
+    }
+
+    return props.dotPath
+      ? nodeDotPathToHistory(decodeMessage, startOffset, props.history, props.dotPath)
+      : nodeToHistory(decodeMessage, startOffset, props.history)
+  }, [props.history.last(), startOffset, props.dotPath])
 
   return (
     <PlotHistory

app/src/components/Tree/TreeNode/TreeNodeTitle.tsx

@@ -1,8 +1,8 @@
 import * as q from '../../../../../backend/src/Model'
 import React, { memo } from 'react'
-import { Base64Message } from '../../../../../backend/src/Model/Base64Message'
 import { Theme, withStyles } from '@material-ui/core'
 import { TopicViewModel } from '../../../model/TopicViewModel'
+import { useDecoder } from '../../hooks/useDecoder'
 
 export interface TreeNodeProps extends React.HTMLAttributes<HTMLElement> {
   treeNode: q.TreeNode<TopicViewModel>
@@ -14,67 +14,72 @@ export interface TreeNodeProps extends React.HTMLAttributes<HTMLElement> {
   classes: any
 }
 
-class TreeNodeTitle extends React.PureComponent<TreeNodeProps, {}> {
-  private renderSourceEdge() {
-    const name = this.props.name || (this.props.treeNode.sourceEdge && this.props.treeNode.sourceEdge.name)
+export const TreeNodeTitle = (props: TreeNodeProps) => {
+  const decodeMessage = useDecoder(props.treeNode)
+
+  function renderSourceEdge() {
+    const name = props.name || (props.treeNode.sourceEdge && props.treeNode.sourceEdge.name)
 
     return (
-      <span key="edge" className={this.props.classes.sourceEdge} data-test-topic={name}>
+      <span key="edge" className={props.classes.sourceEdge} data-test-topic={name}>
         {name}
       </span>
     )
   }
 
-  private truncatedMessage() {
+  function truncatedMessage() {
     const limit = 400
-    if (!this.props.treeNode.message || !this.props.treeNode.message.payload) {
+    if (!props.treeNode.message || !props.treeNode.message.payload) {
       return ''
     }
+    const [value = ''] = decodeMessage(props.treeNode.message)?.message?.format(props.treeNode.type) ?? []
 
-    const str = Base64Message.toUnicodeString(this.props.treeNode.message.payload)
-    return str.length > limit ? `${str.slice(0, limit)}…` : str
+    return value.length > limit ? `${value.slice(0, limit)}…` : value
   }
 
-  private renderValue() {
-    return this.props.treeNode.message &&
-      this.props.treeNode.message.payload &&
-      this.props.treeNode.message.length > 0 ? (
-      <span key="value" className={this.props.classes.value}>
+  function renderValue() {
+    return props.treeNode.message && props.treeNode.message.payload && props.treeNode.message.length > 0 ? (
+      <span key="value" className={props.classes.value}>
         {' '}
-        = {this.truncatedMessage()}
+        = {truncatedMessage()}
       </span>
     ) : null
   }
 
-  private renderExpander() {
-    if (this.props.treeNode.edgeCount() === 0) {
+  function renderExpander() {
+    if (props.treeNode.edgeCount() === 0) {
       return null
     }
 
     return (
-      <span key="expander" className={this.props.classes.expander} onClick={this.props.toggleCollapsed}>
-        {this.props.collapsed ? '▶' : '▼'}
+      <span key="expander" className={props.classes.expander} onClick={props.toggleCollapsed}>
+        {props.collapsed ? '▶' : '▼'}
       </span>
     )
   }
 
-  private renderMetadata() {
-    if (this.props.treeNode.edgeCount() === 0 || !this.props.collapsed) {
+  function renderMetadata() {
+    if (props.treeNode.edgeCount() === 0 || !props.collapsed) {
       return null
     }
 
-    const messages = this.props.treeNode.leafMessageCount()
-    const topicCount = this.props.treeNode.childTopicCount()
+    const messages = props.treeNode.leafMessageCount()
+    const topicCount = props.treeNode.childTopicCount()
     return (
-      <span key="metadata" className={this.props.classes.collapsedSubnodes}>{` (${topicCount} ${
+      <span key="metadata" className={props.classes.collapsedSubnodes}>{` (${topicCount} ${
         topicCount === 1 ? 'topic' : 'topics'
       }, ${messages} ${messages === 1 ? 'message' : 'messages'})`}</span>
     )
   }
 
-  public render() {
-    return [this.renderExpander(), this.renderSourceEdge(), this.renderMetadata(), this.renderValue()]
-  }
+  return (
+    <>
+      {renderExpander()}
+      {renderSourceEdge()}
+      {renderMetadata()}
+      {renderValue()}
+    </>
+  )
 }
 
 const styles = (theme: Theme) => ({

app/src/components/Tree/TreeNode/effects/useViewModel.tsx

@@ -0,0 +1,18 @@
+import * as q from '../../../../../../backend/src/Model'
+import { useEffect } from 'react'
+import { TopicViewModel } from '../../../../model/TopicViewModel'
+
+export function useViewModel(treeNode: q.TreeNode<TopicViewModel> | undefined) {
+  useEffect(() => {
+    if (treeNode && !treeNode?.viewModel) {
+      treeNode.viewModel = new TopicViewModel(treeNode)
+    }
+    treeNode?.viewModel?.retain()
+
+    return function cleanup() {
+      treeNode?.viewModel?.release()
+    }
+  }, [treeNode])
+
+  return treeNode?.viewModel
+}

app/src/components/Tree/TreeNode/effects/useViewModelSubscriptions.tsx

@@ -1,6 +1,8 @@
 import * as q from '../../../../../../backend/src/Model'
-import React, { useEffect } from 'react'
+import React, { useCallback } from 'react'
 import { TopicViewModel } from '../../../../model/TopicViewModel'
+import { useSubscription } from '../../../hooks/useSubscription'
+import { useViewModel } from './useViewModel'
 
 export function useViewModelSubscriptions(
   treeNode: q.TreeNode<TopicViewModel>,
@@ -8,37 +10,21 @@ export function useViewModelSubscriptions(
   setSelected: (value: boolean) => void,
   setCollapsedOverride: (value: boolean) => void
 ) {
-  useEffect(() => {
-    const selectionDidChange = () => {
-      const selected = treeNode.viewModel && treeNode.viewModel.isSelected()
-      treeNode.viewModel && setSelected(Boolean(selected))
+  const viewModel = useViewModel(treeNode)
 
-      if (selected && nodeRef && nodeRef.current) {
-        nodeRef.current.focus({ preventScroll: false })
-      }
-    }
+  const selectionDidChange = useCallback(() => {
+    const selected = viewModel && viewModel.isSelected()
+    viewModel && setSelected(Boolean(selected))
 
-    const expandedDidChange = () => {
-      treeNode.viewModel && setCollapsedOverride(!treeNode.viewModel.isExpanded())
+    if (selected && nodeRef && nodeRef.current) {
+      nodeRef.current.focus({ preventScroll: false })
     }
+  }, [viewModel])
 
-    function addSubscriber() {
-      treeNode.viewModel = new TopicViewModel()
-      treeNode.viewModel.selectionChange.subscribe(selectionDidChange)
-      treeNode.viewModel.expandedChange.subscribe(expandedDidChange)
-    }
+  const expandedDidChange = useCallback(() => {
+    viewModel && setCollapsedOverride(!viewModel.isExpanded())
+  }, [viewModel])
 
-    function removeSubscriber() {
-      if (treeNode.viewModel) {
-        treeNode.viewModel.selectionChange.unsubscribe(selectionDidChange)
-        treeNode.viewModel.expandedChange.unsubscribe(expandedDidChange)
-        treeNode.viewModel = undefined
-      }
-    }
-
-    addSubscriber()
-    return function cleanup() {
-      removeSubscriber()
-    }
-  }, [treeNode])
+  useSubscription(viewModel?.selectionChange, selectionDidChange)
+  useSubscription(viewModel?.expandedChange, expandedDidChange)
 }

app/src/components/UpdateNotifier.tsx

@@ -1,7 +1,6 @@
-import * as compareVersions from 'compare-versions'
-import * as electron from 'electron'
-import * as os from 'os'
-import * as React from 'react'
+import compareVersions from 'compare-versions'
+import electron from 'electron'
+import React from 'react'
 import axios from 'axios'
 import Close from '@material-ui/icons/Close'
 import CloudDownload from '@material-ui/icons/CloudDownload'
@@ -182,9 +181,10 @@ class UpdateNotifier extends React.PureComponent<Props, State> {
 
   private assetForCurrentPlatform(asset: GithubAsset) {
     let regex: RegExp
-    if (os.platform() === 'darwin') {
+    const platform = this.getPlatform()
+    if (platform === 'darwin') {
       regex = /\.dmg$/
-    } else if (os.platform() === 'win32') {
+    } else if (platform === 'win32') {
       regex = /\.exe$/
     } else {
       regex = /\.AppImage$/
@@ -193,6 +193,14 @@ class UpdateNotifier extends React.PureComponent<Props, State> {
     return regex.test(asset.name)
   }
 
+  private getPlatform(): string {
+    if (typeof window === 'undefined') return 'linux'
+    const userAgent = window.navigator.userAgent.toLowerCase()
+    if (userAgent.includes('mac')) return 'darwin'
+    if (userAgent.includes('win')) return 'win32'
+    return 'linux'
+  }
+
   private renderDownloads() {
     const latestUpdate = this.state.newerVersions[0]
     if (!latestUpdate || !latestUpdate.assets) {

app/src/components/helper/Copy.tsx

@@ -9,7 +9,8 @@ import { globalActions } from '../../actions'
 const copy = require('copy-text-to-clipboard')
 
 interface Props {
-  value: string
+  value?: string
+  getValue?: () => string | undefined
   actions: {
     global: typeof globalActions
   }
@@ -28,7 +29,7 @@ class Copy extends React.PureComponent<Props, State> {
   private handleClick = (event: React.MouseEvent) => {
     event.stopPropagation()
 
-    copy(this.props.value)
+    copy(this.props.value ?? this.props.getValue?.())
     this.props.actions.global.showNotification('Copied to clipboard')
     this.setState({ didCopy: true })
     setTimeout(() => {

app/src/components/helper/DateFormatter.tsx

@@ -1,5 +1,5 @@
-import * as moment from 'moment'
-import * as React from 'react'
+import moment from 'moment'
+import React from 'react'
 import { AppState } from '../../reducers'
 import { connect } from 'react-redux'
 
@@ -12,6 +12,7 @@ interface Props {
 }
 
 const unitMapping = {
+  ms: 'milliseconds',
   s: 'seconds',
   m: 'minutes',
   h: 'hours',
@@ -21,7 +22,7 @@ class DateFormatter extends React.PureComponent<Props, {}> {
   private intervalSince(intervalSince: Date) {
     const interval = intervalSince.getTime() - this.props.date.getTime()
     const unit = this.unitForInterval(interval)
-    return `${Math.round(moment.duration(interval).as(unit) * 100) / 100} ${unitMapping[unit]}`
+    return `${moment.duration(interval).as(unit).toFixed(3)} ${unitMapping[unit]}`
   }
 
   private legacyDate() {
@@ -31,10 +32,11 @@ class DateFormatter extends React.PureComponent<Props, {}> {
   private localizedDate(locale: string) {
     return moment(this.props.date)
       .locale(locale)
-      .format(this.props.timeFirst ? 'LTS L' : 'L LTS')
+      .format(this.props.timeFirst ? 'LTS.SSS L' : 'L LTS.SSS')
   }
 
   private unitForInterval(milliseconds: number) {
+    const oneSecond = 1000 * 1
     const oneMinute = 1000 * 60
     const oneHour = oneMinute * 60
 
@@ -46,7 +48,11 @@ class DateFormatter extends React.PureComponent<Props, {}> {
       return 'm'
     }
 
-    return 's'
+    if (milliseconds > oneSecond * 0.5) {
+      return 's'
+    }
+
+    return 'ms'
   }
 
   public render() {

app/src/components/helper/Save.tsx

@@ -0,0 +1,85 @@
+import * as React from 'react'
+import { connect } from 'react-redux'
+import Check from '@material-ui/icons/Check'
+import CustomIconButton from './CustomIconButton'
+
+import { SaveAlt } from '@material-ui/icons'
+import { bindActionCreators } from 'redux'
+import { rendererRpc, writeToFile } from '../../../../events'
+import { makeSaveDialogRpc } from '../../../../events/OpenDialogRequest'
+
+import { globalActions } from '../../actions'
+
+export async function saveToFile(data: string): Promise<string | undefined> {
+  const rejectReasons = {
+    errorWritingFile: 'Error writing file',
+  }
+
+  const { canceled, filePath } = await rendererRpc.call(makeSaveDialogRpc(), {
+    securityScopedBookmarks: true,
+  })
+
+  if (!canceled && filePath !== undefined) {
+    try {
+      const filename = await rendererRpc.call(writeToFile, { filePath, data })
+      return filePath
+    } catch (error) {
+      throw rejectReasons.errorWritingFile
+    }
+  }
+}
+
+interface Props {
+  getData: () => string | undefined
+  actions: {
+    global: typeof globalActions
+  }
+}
+
+interface State {
+  didSave: boolean
+}
+
+class Save extends React.PureComponent<Props, State> {
+  constructor(props: Props) {
+    super(props)
+    this.state = { didSave: false }
+  }
+
+  private handleClick = async (event: React.MouseEvent) => {
+    event.stopPropagation()
+    const data = this.props.getData()
+    if (data != undefined) {
+      const filename = await saveToFile(data)
+      this.props.actions.global.showNotification(`Saved to ${filename}`)
+      this.setState({ didSave: true })
+      setTimeout(() => {
+        this.setState({ didSave: false })
+      }, 1500)
+    }
+  }
+
+  public render() {
+    const icon = !this.state.didSave ? (
+      <SaveAlt fontSize="inherit" />
+    ) : (
+      <Check fontSize="inherit" style={{ cursor: 'default' }} />
+    )
+
+    return (
+      <CustomIconButton onClick={this.handleClick} tooltip="Save to file">
+        <div style={{ marginTop: '2px' }}>{icon}</div>
+      </CustomIconButton>
+    )
+  }
+}
+
+const mapDispatchToProps = (dispatch: any) => {
+  return {
+    actions: {
+      global: bindActionCreators(globalActions, dispatch),
+    },
+  }
+}
+
+export default connect(undefined, mapDispatchToProps)(Save)

app/src/components/hooks/useDecoder.ts

@@ -0,0 +1,31 @@
+import * as q from '../../../../backend/src/Model'
+import { useCallback, useState } from 'react'
+import { TopicViewModel } from '../../model/TopicViewModel'
+import { useSubscription } from './useSubscription'
+import { useViewModel } from '../Tree/TreeNode/effects/useViewModel'
+import { DecoderEnvelope } from '../../decoders/DecoderEnvelope'
+import { Decoder } from '../../../../backend/src/Model/Decoder'
+
+export type DecoderFunction = (message: q.Message) => DecoderEnvelope | undefined
+
+/**
+ * Provides the latest decoder for a topic
+ *
+ * @param treeNode
+ * @returns
+ */
+export function useDecoder(treeNode: q.TreeNode<TopicViewModel> | undefined): DecoderFunction {
+  const viewModel = useViewModel(treeNode)
+  const [decoder, setDecoder] = useState(viewModel?.decoder)
+
+  useSubscription(viewModel?.onDecoderChange, setDecoder)
+
+  return useCallback(
+    message => {
+      return decoder && message.payload
+        ? decoder.decoder.decode(message.payload, decoder.format)
+        : { message: message.payload ?? undefined, decoder: Decoder.NONE }
+    },
+    [decoder]
+  )
+}

app/src/components/hooks/useSubscription.ts

@@ -0,0 +1,10 @@
+import { useEffect } from 'react'
+import { EventDispatcher } from '../../../../events'
+
+export function useSubscription<T>(dispatcher: EventDispatcher<T> | undefined, callback: (value: T) => void) {
+  useEffect(() => {
+    dispatcher?.subscribe(callback)
+
+    return () => dispatcher?.unsubscribe(callback)
+  }, [dispatcher, callback])
+}

app/src/decoders/BinaryDecoder.ts

@@ -0,0 +1,56 @@
+import { Base64Message } from '../../../backend/src/Model/Base64Message'
+import { Decoder } from '../../../backend/src/Model/Decoder'
+import { DecoderEnvelope } from './DecoderEnvelope'
+import { MessageDecoder } from './MessageDecoder'
+
+type BinaryFormats =
+  | 'int8'
+  | 'int16'
+  | 'int32'
+  | 'int64'
+  | 'uint8'
+  | 'uint16'
+  | 'uint32'
+  | 'uint64'
+  | 'float'
+  | 'double'
+
+/**
+ * Binary decode primitive binary data type and arrays of these
+ */
+export const BinaryDecoder: MessageDecoder<BinaryFormats> = {
+  formats: ['int8', 'int16', 'int32', 'int64', 'uint8', 'uint16', 'uint32', 'uint64', 'float', 'double'],
+  decode(input: Base64Message, format: BinaryFormats): DecoderEnvelope {
+    const decodingOption = {
+      int8: [Buffer.prototype.readInt8, 1],
+      int16: [Buffer.prototype.readInt16LE, 2],
+      int32: [Buffer.prototype.readInt32LE, 4],
+      int64: [Buffer.prototype.readBigInt64LE, 8],
+      uint8: [Buffer.prototype.readUint8, 1],
+      uint16: [Buffer.prototype.readUint16LE, 2],
+      uint32: [Buffer.prototype.readUint32LE, 4],
+      uint64: [Buffer.prototype.readBigUint64LE, 8],
+      float: [Buffer.prototype.readFloatLE, 4],
+      double: [Buffer.prototype.readDoubleLE, 8],
+    } as const
+
+    const [readNumber, bytesToRead] = decodingOption[format]
+
+    const buf = input.toBuffer()
+    let str: String[] = []
+    if (buf.length % bytesToRead !== 0) {
+      return {
+        error: 'Data type does not align with message',
+        decoder: Decoder.NONE,
+      }
+    }
+    for (let index = 0; index < buf.length; index += bytesToRead) {
+      str.push((readNumber as any).apply(buf, [index]).toString())
+    }
+
+    return {
+      message: Base64Message.fromString(JSON.stringify(str.length === 1 ? str[0] : str)),
+      decoder: Decoder.NONE,
+    }
+  },
+}

app/src/decoders/DecoderEnvelope.ts

@@ -0,0 +1,8 @@
+import { Base64Message } from '../../../backend/src/Model/Base64Message'
+import { Decoder } from '../../../backend/src/Model/Decoder'
+
+export interface DecoderEnvelope {
+  message?: Base64Message
+  error?: string
+  decoder: Decoder
+}

app/src/decoders/MessageDecoder.ts

@@ -0,0 +1,13 @@
+import { Base64Message } from '../../../backend/src/Model/Base64Message'
+import { DecoderEnvelope } from './DecoderEnvelope'
+
+export interface MessageDecoder<T = string> {
+  /**
+   * Can be used to
+   * @param topic
+   */
+  formats: T[]
+  canDecodeTopic?(topic: string): boolean
+  canDecodeData?(data: Base64Message): boolean
+  decode(input: Base64Message, format: T | string | undefined): DecoderEnvelope
+}

app/src/decoders/SparkplugBDecoder.ts

@@ -0,0 +1,28 @@
+import { Base64Message } from '../../../backend/src/Model/Base64Message'
+import { Decoder } from '../../../backend/src/Model/Decoder'
+import { get } from 'sparkplug-payload'
+import { MessageDecoder } from './MessageDecoder'
+var sparkplug = get('spBv1.0')
+
+export const SparkplugDecoder: MessageDecoder = {
+  formats: ['Sparkplug'],
+  canDecodeTopic(topic: string) {
+    return !!topic.match(/^spBv1\.0\/[^/]+\/[ND](DATA|CMD|DEATH|BIRTH)\/[^/]+(\/[^/]+)?$/u)
+  },
+  decode(input) {
+    try {
+      const message = Base64Message.fromString(
+        JSON.stringify(
+          // @ts-ignore
+          sparkplug.decodePayload(new Uint8Array(input.toBuffer()))
+        )
+      )
+      return { message, decoder: Decoder.SPARKPLUG }
+    } catch {
+      return {
+        error: 'Failed to decode sparkplugb payload',
+        decoder: Decoder.NONE,
+      }
+    }
+  },
+}

app/src/decoders/StringDecoder.ts

@@ -0,0 +1,10 @@
+import { Base64Message } from '../../../backend/src/Model/Base64Message'
+import { Decoder } from '../../../backend/src/Model/Decoder'
+import { MessageDecoder } from './MessageDecoder'
+
+export const StringDecoder: MessageDecoder = {
+  formats: ['string'],
+  decode(input: Base64Message) {
+    return { message: input, decoder: Decoder.NONE }
+  },
+}

app/src/decoders/index.ts

@@ -0,0 +1,6 @@
+import { StringDecoder } from './StringDecoder'
+import { BinaryDecoder } from './BinaryDecoder'
+import { SparkplugDecoder } from './SparkplugBDecoder'
+export * from './MessageDecoder'
+
+export const decoders = [SparkplugDecoder, BinaryDecoder, StringDecoder] as const

app/src/index.tsx

@@ -10,6 +10,7 @@ import { connect, Provider } from 'react-redux'
 import { ThemeProvider } from '@material-ui/styles'
 import './utils/tracking'
 import { themes } from './theme'
+import { BrowserAuthWrapper } from './components/BrowserAuthWrapper'
 
 const composeEnhancers = (window as any).__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose
 const store = createStore(reducers, composeEnhancers(applyMiddleware(reduxThunk, batchDispatchMiddleware)))
@@ -33,7 +34,9 @@ const Application = connect(mapStateToProps)(ApplicationRenderer)
 
 ReactDOM.render(
   <Provider store={store}>
-    <Application />
+    <BrowserAuthWrapper>
+      <Application />
+    </BrowserAuthWrapper>
   </Provider>,
   document.getElementById('app')
 )

app/src/mocks/electron.ts

@@ -0,0 +1,12 @@
+// Mock electron module for browser environment
+export const shell = {
+  openExternal: (url: string) => {
+    if (typeof window !== 'undefined') {
+      window.open(url, '_blank')
+    }
+  },
+}
+
+export default {
+  shell,
+}

app/src/model/LegacyConnectionSettings.ts

@@ -1,5 +1,4 @@
 import { ConnectionOptions, createEmptyConnection } from './ConnectionOptions'
-import { v4 } from 'uuid'
 
 interface LegacyConnectionSettings {
   host: string

app/src/model/TopicViewModel.ts

@@ -1,19 +1,77 @@
+import * as q from '../../../backend/src/Model'
 import { Destroyable } from '../../../backend/src/Model/Destroyable'
+import { MessageDecoder, decoders } from '../decoders'
 import { EventDispatcher } from '../../../events'
 
+function findDecoder<T extends Destroyable>(node: q.TreeNode<T>): TopicDecoder | undefined {
+  const decoder = decoders.find(
+    decoder =>
+      decoder.canDecodeTopic?.(node.path()) || (node.message?.payload && decoder.canDecodeData?.(node.message?.payload))
+  )
+
+  return decoder
+    ? {
+        decoder,
+        format: undefined,
+      }
+    : undefined
+}
+
+type TopicDecoder = { decoder: MessageDecoder; format: string | undefined }
+
 export class TopicViewModel implements Destroyable {
   private selected: boolean
   private expanded: boolean
+  private owner: q.TreeNode<TopicViewModel> | undefined
+  private _decoder?: TopicDecoder
+  /**
+   * Reference counter for useViewModel hook
+   */
+  private referenceCounter = 0
   public selectionChange = new EventDispatcher<void>()
   public expandedChange = new EventDispatcher<void>()
+  public onDecoderChange = new EventDispatcher<TopicDecoder | undefined>()
 
-  public constructor() {
+  get decoder(): TopicDecoder | undefined {
+    if (!this._decoder) {
+      this._decoder = this.owner && findDecoder(this.owner)
+    }
+
+    return this._decoder
+  }
+
+  set decoder(override: TopicDecoder | undefined) {
+    this._decoder = override
+
+    this.onDecoderChange.dispatch(override)
+  }
+
+  public constructor(treeNode: q.TreeNode<TopicViewModel>) {
+    this.owner = treeNode
     this.selected = false
     this.expanded = false
   }
 
+  public retain() {
+    this.referenceCounter += 1
+  }
+
+  public release() {
+    this.referenceCounter -= 1
+    if (this.referenceCounter <= 0) {
+      this.destroy()
+    }
+  }
+
   public destroy() {
+    console.log('destroy', this.referenceCounter)
+    if (this.owner) {
+      this.owner.viewModel = undefined
+      this.owner = undefined
+    }
     this.selectionChange.removeAllListeners()
+    this.onDecoderChange.removeAllListeners()
+    this.expandedChange.removeAllListeners()
   }
 
   public isSelected() {

app/tsconfig.json

@@ -4,38 +4,26 @@
     "noImplicitAny": true,
     "strictNullChecks": true,
     "strict": true,
-    "lib": [
-      "es2017",
-      "dom"
-    ],
+    "lib": ["es2019", "dom"],
     "moduleResolution": "node",
     "outDir": "./build/",
     "sourceMap": true,
     "module": "esnext",
-    "target": "es2017",
+    "target": "ES2017",
     "jsx": "react",
     "paths": {
-      "react": [
-        "./node_modules/@types/react"
-      ]
+      "react": ["./node_modules/@types/react"]
     },
-    "types": [
-      "react"
-    ],
+    "types": ["react"],
     "allowSyntheticDefaultImports": true,
-    "skipLibCheck": true
+    "skipLibCheck": true,
+    "esModuleInterop": true
   },
-  "include": [
-    "./src/**/*"
-  ],
-  "exclude": [
-    "**/*.d.ts",
-    ".src/**/*.png",
-    "./node_modules"
-  ],
+  "include": ["./src/**/*"],
+  "exclude": ["**/*.d.ts", ".src/**/*.png", "./node_modules"],
   "awesomeTypescriptLoaderOptions": {
     "useCache": true,
     "transpileModule": true,
     "errorsAsWarnings": true
   }
-}
+}

app/webpack.browser.config.js

@@ -0,0 +1,102 @@
+// Browser-specific webpack configuration
+const HtmlWebpackPlugin = require('html-webpack-plugin')
+const webpack = require('webpack')
+const path = require('path')
+
+module.exports = {
+  entry: {
+    app: './src/index.tsx',
+    bugtracking: './src/utils/bugtracking.ts',
+  },
+  output: {
+    chunkFilename: '[name].bundle.js',
+    filename: '[name].bundle.js',
+    path: `${__dirname}/build`,
+  },
+  optimization: {
+    minimize: false,
+    splitChunks: {
+      chunks: 'all',
+      minSize: 30000,
+      minChunks: 1,
+      maxAsyncRequests: 5,
+      maxInitialRequests: 3,
+      automaticNameDelimiter: '~',
+      cacheGroups: {
+        vendors: {
+          test: /[\\/]node_modules[\\/](react|react-dom|@material-ui|popper\.js|react|react-redux|prop-types|jss|redux|scheduler|react-transition-group)[\\/]/,
+          name: 'vendors',
+          chunks: 'all',
+          priority: -10,
+        },
+        default: {
+          name: 'default',
+          minChunks: 2,
+          priority: -20,
+          reuseExistingChunk: true,
+        },
+      },
+    },
+    runtimeChunk: 'single',
+  },
+  devServer: {
+    hot: true,
+    liveReload: true,
+  },
+  target: 'web', // Changed from 'electron-renderer' to 'web'
+  mode: 'production',
+  devtool: 'source-map',
+  resolve: {
+    extensions: ['.ts', '.mjs', '.m.js', '.tsx', '.js', '.json'],
+    modules: ['node_modules', path.resolve(__dirname, 'node_modules')],
+    alias: {
+      electron: require.resolve('./src/mocks/electron.ts'),
+    },
+    fallback: {
+      // Browser fallbacks for Node.js modules
+      path: require.resolve('path-browserify'),
+      fs: false,
+      crypto: false,
+      url: require.resolve('url/'),
+      os: require.resolve('os-browserify/browser'),
+      events: require.resolve('events/'),
+    },
+  },
+  module: {
+    rules: [
+      {
+        test: /\.tsx?$/,
+        use: [
+          {
+            loader: 'ts-loader',
+            options: {
+              transpileOnly: true, // Skip type checking, we already did it with tsc
+            },
+          },
+        ],
+        exclude: /node_modules/,
+      },
+      { enforce: 'pre', test: /\.js$/, loader: 'source-map-loader' },
+      {
+        test: /\.css$/,
+        use: ['style-loader', 'css-loader'],
+      },
+      {
+        test: /\.(png|jpg|gif)$/i,
+        type: 'asset/resource',
+      },
+    ],
+  },
+  plugins: [
+    new HtmlWebpackPlugin({ template: './index.html', file: './build/index.html', inject: false }),
+    new webpack.DefinePlugin({
+      'process.env.BROWSER_MODE': JSON.stringify('true'),
+    }),
+    new webpack.NormalModuleReplacementPlugin(/EventSystem[\\/]EventBus$/, resource => {
+      console.log('Replacing EventBus:', resource.request);
+      resource.request = resource.request.replace(/EventBus$/, 'BrowserEventBus');
+    }),
+  ],
+  externals: {},
+  cache: false,
+}

app/webpack.config.js

@@ -41,6 +41,7 @@ module.exports = {
   devServer: {
     // contentBase: './dist', // content not from webpack
     hot: true,
+    liveReload: true,
   },
   target: 'electron-renderer',
   mode: 'production',
@@ -54,7 +55,15 @@ module.exports = {
       // All files with a '.ts' or '.tsx' extension will be handled by 'awesome-typescript-loader'.
       {
         test: /\.tsx?$/,
-        loader: 'ts-loader',
+        use: [
+          {
+            loader: 'ts-loader',
+            // options: {
+            //   configFile: './tsconfig.json',
+            // },
+          },
+        ],
+        exclude: /node_modules/,
       },
       // All output '.js' files will have any sourcemaps re-processed by 'source-map-loader'.
       { enforce: 'pre', test: /\.js$/, loader: 'source-map-loader' },
@@ -81,7 +90,6 @@ module.exports = {
   plugins: [
     new HtmlWebpackPlugin({ template: './index.html', file: './build/index.html', inject: false }),
     // new BundleAnalyzerPlugin(),
-    new webpack.HotModuleReplacementPlugin(),
     // new webpack.IgnorePlugin({
     //   resourceRegExp: /\.\/build\/Debug\/addon/,
     //   contextRegExp: /heapdump$/
@@ -96,4 +104,10 @@ module.exports = {
     // "react": "React",
     // "react-dom": "ReactDOM"
   },
+  cache: {
+    type: 'filesystem',
+  },
+  optimization: {
+    runtimeChunk: 'single',
+  },
 }

backend/package.json

@@ -4,15 +4,14 @@
   "description": "",
   "main": "build/index.js",
   "scripts": {
-    "test": "mocha --require ts-node/register --require source-map-support/register --recursive ./src/*/**/*.spec.ts",
+    "test": "NODE_PATH=../node_modules TS_NODE_PROJECT=./tsconfig.json mocha --require ts-node/register --require source-map-support/register --recursive ./src/*/**/*.spec.ts",
     "build": "tsc",
-    "test-inspect": "mocha --inspect-brk --require ts-node/register --require source-map-support/register --recursive ./src/*/**/*.spec.ts",
-    "coverage": "nyc mocha --require ts-node/register --require source-map-support/register --recursive ./src/*/**/*.spec.ts",
-    "debug": "ts-node --inspect ./src/index.ts",
-    "postinstall": "yarn build"
+    "test-inspect": "NODE_PATH=../node_modules TS_NODE_PROJECT=./tsconfig.json mocha --inspect-brk --require ts-node/register --require source-map-support/register --recursive ./src/*/**/*.spec.ts",
+    "coverage": "NODE_PATH=../node_modules TS_NODE_PROJECT=./tsconfig.json nyc mocha --require ts-node/register --require source-map-support/register --recursive ./src/*/**/*.spec.ts",
+    "debug": "ts-node --inspect ./src/index.ts"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=20"
   },
   "author": "",
   "license": "CC-BY-ND-4.0",
@@ -38,12 +37,31 @@
     "sourceMap": true,
     "instrument": true
   },
-  "peerDependencies": {
-    "fs-extra": "^8.0.1",
-    "js-base64": "^2.5.1",
-    "long": "^4.0.0",
+  "dependencies": {
+    "@types/sha1": "^1.1.5",
+    "builder-util-runtime": "^9",
+    "fs-extra": "9",
+    "js-base64": "^3.7.2",
     "lowdb": "^1.0.0",
-    "mqtt": "^3.0.0",
-    "protobufjs": "^6.11.4"
+    "mqtt": "^4.3.6",
+    "protobufjs": "^8.0.0",
+    "sha1": "^1.1.1",
+    "uuid": "^8.3.2"
+  },
+  "devDependencies": {
+    "@types/chai": "^4.1.7",
+    "@types/fs-extra": "8",
+    "@types/lowdb": "^1.0.6",
+    "@types/mocha": "^7.0.2",
+    "@types/node": "^25.0.3",
+    "@types/sha1": "^1.1.1",
+    "@types/uuid": "^8.3.4",
+    "chai": "^4.2.0",
+    "electron": "29.2.0",
+    "mocha": "^10.4.0",
+    "nyc": "15",
+    "source-map-support": "^0.5.9",
+    "ts-node": "^10.9.2",
+    "typescript": "^4.5.5"
   }
-}
+}

backend/src/ConfigStorage.ts

@@ -1,15 +1,18 @@
-import * as FileAsync from 'lowdb/adapters/FileAsync'
-import * as fs from 'fs-extra'
-import * as lowdb from 'lowdb'
-import * as path from 'path'
-import { backendRpc } from '../../events'
+import FileAsync from 'lowdb/adapters/FileAsync'
+import fs from 'fs-extra'
+import lowdb from 'lowdb'
+import path from 'path'
+import { Rpc } from '../../events/EventSystem/Rpc'
 import { storageClearEvent, storageLoadEvent, storageStoreEvent } from '../../events/StorageEvents'
 
 export default class ConfigStorage {
   private file: string
   private database: any
-  constructor(file: string) {
+  private rpc: Rpc
+
+  constructor(file: string, rpc: Rpc) {
     this.file = file
+    this.rpc = rpc
   }
 
   private async getDb() {
@@ -26,13 +29,13 @@ export default class ConfigStorage {
   }
 
   public async init() {
-    backendRpc.on(storageStoreEvent, async event => {
+    this.rpc.on(storageStoreEvent, async event => {
       const db = await this.getDb()
       await db.set(event.store, event.data).write()
       return
     })
 
-    backendRpc.on(storageLoadEvent, async event => {
+    this.rpc.on(storageLoadEvent, async event => {
       const db = await this.getDb()
       const data = await db.get(event.store).value()
       return {
@@ -41,7 +44,7 @@ export default class ConfigStorage {
       }
     })
 
-    backendRpc.on(storageClearEvent, async event => {
+    this.rpc.on(storageClearEvent, async event => {
       const db = await this.getDb()
       const keys = await db.keys().value()
       for (const key of keys) {

backend/src/DataSource/MqttSource.ts

@@ -98,7 +98,7 @@ export class MqttSource implements DataSource<MqttOptions> {
 
   public publish(msg: MqttMessage) {
     if (this.client) {
-      this.client.publish(msg.topic, msg.payload ? Base64Message.toUnicodeString(msg.payload) : '', {
+      this.client.publish(msg.topic, (msg.payload && new Base64Message(msg.payload))?.toBuffer() ?? '', {
         qos: msg.qos,
         retain: msg.retain,
       })

backend/src/Model/Base64Message.ts

@@ -1,31 +1,93 @@
 import { Base64 } from 'js-base64'
-import { Decoder } from './Decoder'
+import { TopicDataType } from './TreeNode'
+
+export type Base64MessageDTO = Pick<Base64Message, 'base64Message'>
 
 export class Base64Message {
-  private base64Message: string
-  private unicodeValue: string
-  public decoder: Decoder
-  public length: number
+  public base64Message: string
+  private _unicodeValue: string | undefined
 
-  private constructor(base64Str: string) {
-    this.base64Message = base64Str
-    this.unicodeValue = Base64.decode(base64Str)
-    this.length = base64Str.length
-    this.decoder = Decoder.NONE
+  // Todo: Rename to `encodedLength`
+  public get length(): number {
+    return this.base64Message.length
   }
 
-  public static toUnicodeString(message: Base64Message) {
-    return message.unicodeValue || ''
+  private get unicodeValue(): string {
+    if (!this._unicodeValue) {
+      this._unicodeValue = Base64.decode(this.base64Message ?? '')
+    }
+
+    return this._unicodeValue
+  }
+
+  constructor(base64Str?: string | Base64MessageDTO, error?: string) {
+    if (typeof base64Str === 'string' || typeof base64Str === 'undefined') {
+      this.base64Message = base64Str ?? ''
+    } else {
+      if (typeof base64Str.base64Message !== 'string') {
+        throw new Error('Received unexpected type in copy constructor')
+      }
+      this.base64Message = base64Str.base64Message
+    }
+  }
+
+  /**
+   * Override default JSON serialization behavior to only return the DTO
+   * @returns
+   */
+  public toJSON(): Base64MessageDTO {
+    return { base64Message: this.base64Message }
+  }
+
+  public toUnicodeString() {
+    return this.unicodeValue || ''
   }
 
   public static fromBuffer(buffer: Buffer) {
     return new Base64Message(buffer.toString('base64'))
   }
 
+  public toBuffer(): Buffer {
+    return Buffer.from(this.base64Message, 'base64')
+  }
+
   public static fromString(str: string) {
     return new Base64Message(Base64.encode(str))
   }
 
+  public format(type: TopicDataType = 'string'): [string, 'json' | undefined] {
+    try {
+      switch (type) {
+        case 'json': {
+          const json = JSON.parse(this.toUnicodeString())
+          return [JSON.stringify(json, undefined, '  '), 'json']
+        }
+        case 'hex': {
+          const hex = Base64Message.toHex(this)
+          return [hex, undefined]
+        }
+        default: {
+          const str = this.toUnicodeString()
+          return [str, undefined]
+        }
+      }
+    } catch (error) {
+      const str = this.toUnicodeString()
+      return [str, undefined]
+    }
+  }
+
+  public static toHex(message: Base64Message) {
+    const buf = Buffer.from(message.base64Message, 'base64')
+
+    let str: string = ''
+    buf.forEach(element => {
+      const hex = element.toString(16).toUpperCase()
+      str += `0x${hex.length < 2 ? '0' + hex : hex} `
+    })
+    return str.trimRight()
+  }
+
   public static toDataUri(message: Base64Message, mimeType: string) {
     return `data:${mimeType};base64,${message.base64Message}`
   }

backend/src/Model/ChangeBuffer.ts

@@ -15,7 +15,7 @@ export class ChangeBuffer {
   public push(val: MqttMessage) {
     if (!this.isFull()) {
       this.buffer.push({ message: val, received: new Date() })
-      this.size += this.estimatedMessageOverhead + (val.payload ? val.payload.length : 0)
+      this.size += this.estimatedMessageOverhead + (val.payload?.base64Message.length ?? 0)
       this.length += 1
     }
   }

backend/src/Model/Message.ts

@@ -1,7 +1,8 @@
 import { Base64Message } from './Base64Message'
 import { QoS } from '../DataSource/MqttSource'
+import { MemoryConsumptionExpressedByLength } from './RingBuffer'
 
-export interface Message {
+export interface Message extends MemoryConsumptionExpressedByLength {
   // mqtt based info
   payload: Base64Message | null
   messageId?: number

backend/src/Model/TreeNode.ts

@@ -2,6 +2,8 @@ import { Destroyable } from './Destroyable'
 import { Edge, Message, RingBuffer, MessageHistory } from './'
 import { EventDispatcher } from '../../../events'
 
+export type TopicDataType = 'string' | 'json' | 'hex'
+
 export class TreeNode<ViewModel extends Destroyable> {
   public sourceEdge?: Edge<ViewModel>
   public message?: Message
@@ -17,6 +19,7 @@ export class TreeNode<ViewModel extends Destroyable> {
   public onMessage = new EventDispatcher<Message>()
   public onDestroy = new EventDispatcher<TreeNode<ViewModel>>()
   public isTree = false
+  public type: TopicDataType = 'json'
 
   private cachedPath?: string
   private cachedChildTopics?: Array<TreeNode<ViewModel>>
@@ -153,7 +156,7 @@ export class TreeNode<ViewModel extends Destroyable> {
 
   public path(): string {
     if (!this.cachedPath) {
-      return this.branch()
+      this.cachedPath = this.branch()
         .map(node => node.sourceEdge && node.sourceEdge.name)
         .filter(name => name !== undefined)
         .join('/')

backend/src/Model/TreeNodeFactory.ts

@@ -1,6 +1,7 @@
 import { Destroyable } from './Destroyable'
 import { Edge, Tree, TreeNode } from './'
 import { MqttMessage } from '../../../events'
+import { Base64Message } from './Base64Message'
 
 export abstract class TreeNodeFactory {
   private static messageCounter = 0
@@ -30,7 +31,8 @@ export abstract class TreeNodeFactory {
     mqttMessage.retain
     node.setMessage({
       ...mqttMessage,
-      length: mqttMessage.payload?.length ?? 0,
+      payload: mqttMessage.payload && new Base64Message(mqttMessage.payload?.base64Message),
+      length: mqttMessage.payload?.base64Message.length ?? 0,
       received: receiveDate,
       messageNumber: this.messageCounter,
     })

backend/src/Model/index.ts

@@ -1,5 +1,5 @@
 export { Edge } from './Edge'
-export { TreeNode } from './TreeNode'
+export { TreeNode, TopicDataType } from './TreeNode'
 export { Message } from './Message'
 export { TreeNodeFactory } from './TreeNodeFactory'
 export { Tree } from './Tree'

backend/src/Model/sparkplugb.ts

@@ -1,21 +0,0 @@
-import { Base64Message } from './Base64Message'
-import { Decoder } from './Decoder'
-import { get } from 'sparkplug-payload'
-var sparkplug = get("spBv1.0")
-
-export const SparkplugDecoder = {
-  decode(input: Buffer): Base64Message {
-    try {
-      const message = Base64Message.fromString(JSON.stringify(
-        // @ts-ignore
-        sparkplug.decodePayload(new Uint8Array(input)))
-      )
-      message.decoder = Decoder.SPARKPLUG
-      return message
-    } catch {
-      const message = Base64Message.fromString("Failed to decode sparkplugb payload")
-      message.decoder = Decoder.NONE
-      return message
-    }
-  },
-}

backend/src/Model/spec/TreeNode.spec.ts

@@ -1,7 +1,6 @@
 import 'mocha'
 
 import { expect } from 'chai'
-import { Base64Message } from '../Base64Message'
 import { makeTreeNode } from './makeTreeNode'
 
 describe('TreeNode', () => {
@@ -14,7 +13,7 @@ describe('TreeNode', () => {
   it('updateWithNode should update value', () => {
     const topics = 'foo/bar'.split('/')
     const leaf = makeTreeNode('foo/bar', '3')
-    expect(Base64Message.toUnicodeString(leaf.message!.payload!)).to.eq('3')
+    expect(leaf.message!.payload!.toUnicodeString()).to.eq('3')
 
     const updateLeave = makeTreeNode('foo/bar', '5')
 
@@ -22,13 +21,13 @@ describe('TreeNode', () => {
     root.updateWithNode(updateLeave.firstNode())
 
     expect(root.sourceEdge).to.eq(undefined)
-    expect(Base64Message.toUnicodeString(leaf.message!.payload!)).to.eq('5')
+    expect(leaf.message!.payload!.toUnicodeString()).to.eq('5')
   })
 
   it('updateWithNode should update intermediate nodes', () => {
     const topics1 = 'foo/bar/baz'.split('/')
     const leaf = makeTreeNode('foo/bar/baz', '3')
-    expect(Base64Message.toUnicodeString(leaf.message!.payload!)).to.eq('3')
+    expect(leaf.message!.payload!.toUnicodeString()).to.eq('3')
 
     const topics2 = 'foo/bar'.split('/')
     const updateLeave = makeTreeNode('foo/bar', '5')
@@ -37,10 +36,10 @@ describe('TreeNode', () => {
 
     const barNode = leaf.firstNode().findNode('foo/bar')
     expect(barNode && barNode.sourceEdge && barNode.sourceEdge.name).to.eq('bar')
-    expect(Base64Message.toUnicodeString(barNode!.message!.payload!)).to.eq('5')
+    expect(barNode!.message!.payload!.toUnicodeString()).to.eq('5')
 
     expect(leaf.sourceEdge && leaf.sourceEdge.name).to.eq('baz')
-    expect(Base64Message.toUnicodeString(leaf.message!.payload!)).to.eq('3')
+    expect(leaf.message!.payload!.toUnicodeString()).to.eq('3')
   })
 
   it('updateWithNode should add nodes to the tree', () => {

backend/src/Model/spec/TreeNodeFactory.spec.ts

@@ -1,6 +1,5 @@
 import 'mocha'
 import { expect } from 'chai'
-import { Base64Message } from '../Base64Message'
 import { makeTreeNode } from './makeTreeNode'
 
 describe('TreeNodeFactory', () => {
@@ -20,7 +19,7 @@ describe('TreeNodeFactory', () => {
 
     expect(node).to.not.eq(undefined)
     expect(node.sourceEdge.name).to.eq('bar')
-    expect(Base64Message.toUnicodeString(node.message.payload!)).to.eq('5')
+    expect(node.message.payload!.toUnicodeString()).to.eq('5')
 
     const foo = node.firstNode().findNode('foo')
     expect(foo && foo.sourceEdge && foo.sourceEdge.name).to.eq('foo')
@@ -34,7 +33,7 @@ describe('TreeNodeFactory', () => {
       return
     }
 
-    expect(Base64Message.toUnicodeString(node.message.payload!)).to.eq('5')
+    expect(node.message.payload!.toUnicodeString()).to.eq('5')
     expect(node.sourceEdge.name).to.eq('baz')
 
     const barNode = node.sourceEdge.source

backend/src/index.ts

@@ -4,16 +4,20 @@ import {
   AddMqttConnection,
   MqttMessage,
   addMqttConnectionEvent,
-  backendEvents,
   makeConnectionMessageEvent,
   makeConnectionStateEvent,
   makePublishEvent,
   removeConnection,
 } from '../../events'
-import { SparkplugDecoder } from './Model/sparkplugb'
+import { EventBusInterface } from '../../events/EventSystem/EventBusInterface'
 
 export class ConnectionManager {
   private connections: { [s: string]: DataSource<any> } = {}
+  private backendEvents: EventBusInterface
+
+  constructor(backendEvents: EventBusInterface) {
+    this.backendEvents = backendEvents
+  }
 
   private handleConnectionRequest = (event: AddMqttConnection) => {
     const connectionId = event.id
@@ -29,12 +33,12 @@ export class ConnectionManager {
 
     const connectionStateEvent = makeConnectionStateEvent(connectionId)
     connection.stateMachine.onUpdate.subscribe(state => {
-      backendEvents.emit(connectionStateEvent, state)
+      this.backendEvents.emit(connectionStateEvent, state)
     })
 
     connection.connect(options)
     this.handleNewMessagesForConnection(connectionId, connection)
-    backendEvents.subscribe(makePublishEvent(connectionId), (msg: MqttMessage) => {
+    this.backendEvents.subscribe(makePublishEvent(connectionId), (msg: MqttMessage) => {
       this.connections[connectionId].publish(msg)
     })
   }
@@ -48,14 +52,9 @@ export class ConnectionManager {
       }
 
       let decoded_payload = null
-      // spell-checker: disable-next-line
-      if (topic.match(/^spBv1\.0\/[^/]+\/[ND](DATA|CMD|DEATH|BIRTH)\/[^/]+(\/[^/]+)?$/u)) {
-        decoded_payload = SparkplugDecoder.decode(buffer)
-      } else {
-        decoded_payload = Base64Message.fromBuffer(buffer)
-      }
+      decoded_payload = Base64Message.fromBuffer(buffer)
 
-      backendEvents.emit(messageEvent, {
+      this.backendEvents.emit(messageEvent, {
         topic,
         payload: decoded_payload,
         qos: packet.qos,
@@ -66,8 +65,8 @@ export class ConnectionManager {
   }
 
   public manageConnections() {
-    backendEvents.subscribe(addMqttConnectionEvent, this.handleConnectionRequest)
-    backendEvents.subscribe(removeConnection, (connectionId: string) => {
+    this.backendEvents.subscribe(addMqttConnectionEvent, this.handleConnectionRequest)
+    this.backendEvents.subscribe(removeConnection, (connectionId: string) => {
       this.removeConnection(connectionId)
     })
   }
@@ -75,7 +74,7 @@ export class ConnectionManager {
   public removeConnection(connectionId: string) {
     const connection = this.connections[connectionId]
     if (connection) {
-      backendEvents.unsubscribeAll(makePublishEvent(connectionId))
+      this.backendEvents.unsubscribeAll(makePublishEvent(connectionId))
       connection.disconnect()
       delete this.connections[connectionId]
       connection.stateMachine.onUpdate.removeAllListeners()

backend/tsconfig.json

@@ -6,11 +6,21 @@
     "strictNullChecks": true,
     "outDir": "./build",
     "strict": true,
+    "module": "commonjs",
+    "moduleResolution": "node",
+    "target": "ES2017",
     "lib": [
       "es2017",
       "dom"
     ],
-    "sourceMap": true
+    "sourceMap": true,
+    "esModuleInterop": true
+  },
+  "ts-node": {
+    "compilerOptions": {
+      "module": "commonjs"
+    },
+    "transpileOnly": true
   },
   "includes": [
     "src/**/*.ts"
@@ -20,6 +30,8 @@
     "node_modules",
     "src/**/*.spec.ts",
     "**/*.d.ts",
-    "typings"
+    "typings",
+    "../events",
+    "../app"
   ]
 }

events/EventSystem/BrowserEventBus.ts

@@ -0,0 +1,29 @@
+// Browser-specific EventBus implementation using Socket.io
+import io from 'socket.io-client'
+import { SocketIOClientEventBus } from './SocketIOClientEventBus'
+import { Rpc } from './Rpc'
+
+// Get auth from sessionStorage or use empty (will show login dialog)
+const username = typeof sessionStorage !== 'undefined' ? sessionStorage.getItem('mqtt-explorer-username') || '' : ''
+const password = typeof sessionStorage !== 'undefined' ? sessionStorage.getItem('mqtt-explorer-password') || '' : ''
+
+// Connect to the server (same origin in browser mode)
+const socket = io({
+  auth: {
+    username,
+    password,
+  },
+  reconnection: true,
+  reconnectionDelay: 1000,
+  reconnectionDelayMax: 5000,
+  reconnectionAttempts: Infinity,
+  transports: ['websocket', 'polling'],
+})
+
+export const rendererEvents = new SocketIOClientEventBus(socket)
+export const rendererRpc = new Rpc(rendererEvents)
+
+// In browser mode, the backend is on the server
+// For compatibility, export same instances (renderer communicates with server backend via socket)
+export const backendEvents = rendererEvents
+export const backendRpc = rendererRpc

events/EventSystem/IpcMainEventBus.ts

@@ -1,24 +1,54 @@
-import { IpcMain } from 'electron'
+import { IpcMain, WebContents } from 'electron'
 import { Event } from '../Events'
 import { EventBusInterface } from './EventBusInterface'
 
 export class IpcMainEventBus implements EventBusInterface {
   private ipc: IpcMain
-  private client: any
+  private clients: Map<number, WebContents> = new Map() // webContentsId -> WebContents
+  private connectionOwners: Map<string, number> = new Map() // connectionId -> webContentsId
+  private currentClient: WebContents | undefined
+
   constructor(ipc: IpcMain) {
     this.ipc = ipc
   }
 
   public subscribe<MessageType>(subscribeEvent: Event<MessageType>, callback: (msg: MessageType) => void) {
-    console.log('subscribing', subscribeEvent.topic)
     this.ipc.on(subscribeEvent.topic, (event: any, arg: any) => {
-      this.client = event.sender
+      const sender = event.sender as WebContents
+      this.currentClient = sender
+
+      // Track the client (O(1) operation)
+      if (!this.clients.has(sender.id)) {
+        this.clients.set(sender.id, sender)
+
+        // Clean up when window is closed
+        sender.once('destroyed', () => {
+          this.clients.delete(sender.id)
+
+          // Clean up owned connections
+          Array.from(this.connectionOwners.entries()).forEach(([connectionId, webContentsId]) => {
+            if (webContentsId === sender.id) {
+              this.connectionOwners.delete(connectionId)
+            }
+          })
+        })
+      }
+
+      // Track connection ownership
+      if (subscribeEvent.topic === 'connection/add/mqtt' && arg?.id) {
+        this.connectionOwners.set(arg.id, sender.id)
+      }
+
+      // Remove connection ownership
+      if (subscribeEvent.topic === 'connection/remove' && typeof arg === 'string') {
+        this.connectionOwners.delete(arg)
+      }
+
       callback(arg)
     })
   }
 
   public unsubscribeAll<MessageType>(event: Event<MessageType>) {
-    console.log('unsubscribeAll', event.topic)
     this.ipc.removeAllListeners(event.topic)
   }
 
@@ -27,8 +57,44 @@ export class IpcMainEventBus implements EventBusInterface {
   }
 
   public emit<MessageType>(event: Event<MessageType>, msg: MessageType) {
-    if (!this.client.isDestroyed()) {
-      this.client.send(event.topic, msg)
+    const topic = event.topic
+
+    // RPC responses go only to the requesting client
+    if (topic.includes('/response/')) {
+      if (this.currentClient && !this.currentClient.isDestroyed()) {
+        this.currentClient.send(topic, msg)
+      }
+      return
     }
+
+    // Connection-specific events - optimized with early pattern match
+    if (topic.startsWith('conn/')) {
+      const parts = topic.split('/')
+      let connectionId: string | undefined
+
+      if (parts.length === 2) {
+        connectionId = parts[1]
+      } else if (parts.length === 3 && (parts[1] === 'state' || parts[1] === 'publish')) {
+        connectionId = parts[2]
+      }
+
+      if (connectionId) {
+        const ownerWebContentsId = this.connectionOwners.get(connectionId)
+        if (ownerWebContentsId !== undefined) {
+          const ownerClient = this.clients.get(ownerWebContentsId)
+          if (ownerClient && !ownerClient.isDestroyed()) {
+            ownerClient.send(topic, msg)
+            return
+          }
+        }
+      }
+    }
+
+    // All other events go to all clients
+    this.clients.forEach(client => {
+      if (!client.isDestroyed()) {
+        client.send(topic, msg)
+      }
+    })
   }
 }

events/EventSystem/IpcMainEventBusV2.ts

@@ -0,0 +1,61 @@
+import { IpcMain } from 'electron'
+import { Event } from '../Events'
+import { EventBusInterface } from './EventBusInterface'
+import { MessageCodec } from './MessageCodec'
+
+/**
+ * Enhanced IPC Main Event Bus with Protobuf support
+ *
+ * This version uses binary serialization for better performance
+ * while maintaining backward compatibility with the old JSON-based system.
+ */
+export class IpcMainEventBusV2 implements EventBusInterface {
+  private ipc: IpcMain
+  private client: any
+  private useBinary: boolean
+
+  constructor(ipc: IpcMain, useBinary: boolean = true) {
+    this.ipc = ipc
+    this.useBinary = useBinary
+  }
+
+  public subscribe<MessageType>(subscribeEvent: Event<MessageType>, callback: (msg: MessageType) => void) {
+    console.log('subscribing', subscribeEvent.topic, this.useBinary ? '(binary)' : '(json)')
+    this.ipc.on(subscribeEvent.topic, (event: any, arg: any) => {
+      this.client = event.sender
+
+      if (this.useBinary && arg instanceof Uint8Array) {
+        // Binary message - decode it
+        const { data } = MessageCodec.decodeWithPayload<MessageType>(arg)
+        callback(data)
+      } else {
+        // Regular JSON message
+        callback(arg)
+      }
+    })
+  }
+
+  public unsubscribeAll<MessageType>(event: Event<MessageType>) {
+    console.log('unsubscribeAll', event.topic)
+    this.ipc.removeAllListeners(event.topic)
+  }
+
+  public unsubscribe<MessageType>(event: Event<MessageType>, callback: any) {
+    throw new Error('Not implemented') // Todo: implement
+  }
+
+  public emit<MessageType>(event: Event<MessageType>, msg: MessageType) {
+    if (!this.client || this.client.isDestroyed()) {
+      return
+    }
+
+    if (this.useBinary) {
+      // Encode as binary
+      const binary = MessageCodec.encode(event.topic, msg)
+      this.client.send(event.topic, binary)
+    } else {
+      // Send as JSON (legacy)
+      this.client.send(event.topic, msg)
+    }
+  }
+}

events/EventSystem/IpcRendererEventBusV2.ts

@@ -0,0 +1,65 @@
+import { CallbackStore } from './CallbackStore'
+import { EventBusInterface } from './EventBusInterface'
+import { Event } from '../Events'
+import { IpcRenderer } from 'electron'
+import { MessageCodec } from './MessageCodec'
+
+/**
+ * Enhanced IPC Renderer Event Bus with Protobuf support
+ *
+ * This version uses binary serialization for better performance
+ * while maintaining backward compatibility with the old JSON-based system.
+ */
+export class IpcRendererEventBusV2 implements EventBusInterface {
+  private ipc: IpcRenderer
+  private callbacks: Array<CallbackStore> = []
+  private useBinary: boolean
+
+  constructor(ipc: IpcRenderer, useBinary: boolean = true) {
+    this.ipc = ipc
+    this.useBinary = useBinary
+  }
+
+  public subscribe<MessageType>(event: Event<MessageType>, callback: (msg: MessageType) => void) {
+    const wrappedCallback = (_: any, arg: any) => {
+      if (this.useBinary && arg instanceof Uint8Array) {
+        // Binary message - decode it
+        const { data } = MessageCodec.decodeWithPayload<MessageType>(arg)
+        callback(data)
+      } else {
+        // Regular JSON message
+        callback(arg)
+      }
+    }
+    console.log('subscribing', event.topic, this.useBinary ? '(binary)' : '(json)')
+    this.ipc.on(event.topic, wrappedCallback)
+    this.callbacks.push({
+      callback,
+      wrappedCallback,
+    })
+  }
+
+  public unsubscribeAll<MessageType>(event: Event<MessageType>) {
+    this.ipc.removeAllListeners(event.topic)
+  }
+
+  public unsubscribe<MessageType>(event: Event<MessageType>, callback: any) {
+    const item = this.callbacks.find(store => store.callback === callback)
+    if (!item) {
+      return
+    }
+    this.ipc.removeListener(event.topic, item.wrappedCallback)
+    this.callbacks = this.callbacks.filter(a => a !== item)
+  }
+
+  public emit<MessageType>(event: Event<MessageType>, msg: MessageType) {
+    if (this.useBinary) {
+      // Encode as binary
+      const binary = MessageCodec.encode(event.topic, msg)
+      this.ipc.send(event.topic, binary)
+    } else {
+      // Send as JSON (legacy)
+      this.ipc.send(event.topic, msg)
+    }
+  }
+}

events/EventSystem/MessageCodec.ts

@@ -0,0 +1,74 @@
+/**
+ * Binary Message Codec using Protobuf
+ *
+ * This provides efficient binary serialization for IPC messages,
+ * avoiding JSON stringify/parse overhead.
+ */
+
+import * as protobuf from 'protobufjs'
+
+// Define message schema
+const messageSchema = {
+  nested: {
+    mqtt: {
+      nested: {
+        Envelope: {
+          fields: {
+            topic: { type: 'string', id: 1 },
+            payload: { type: 'bytes', id: 2 },
+          },
+        },
+      },
+    },
+  },
+}
+
+// Create root from JSON schema
+const root = protobuf.Root.fromJSON(messageSchema)
+const Envelope = root.lookupType('mqtt.Envelope')
+
+export interface BinaryMessage {
+  topic: string
+  payload: Uint8Array
+}
+
+export class MessageCodec {
+  /**
+   * Encode a message to binary format
+   */
+  public static encode(topic: string, data: any): Uint8Array {
+    // Serialize the payload to JSON, then to bytes
+    const jsonString = JSON.stringify(data)
+    const payloadBytes = new TextEncoder().encode(jsonString)
+
+    // Create protobuf envelope
+    const message = Envelope.create({
+      topic,
+      payload: payloadBytes,
+    })
+
+    // Encode to binary
+    return Envelope.encode(message).finish()
+  }
+
+  /**
+   * Decode a binary message
+   */
+  public static decode(binary: Uint8Array): BinaryMessage {
+    const message = Envelope.decode(binary) as any
+    return {
+      topic: message.topic,
+      payload: message.payload,
+    }
+  }
+
+  /**
+   * Decode and parse payload as JSON
+   */
+  public static decodeWithPayload<T>(binary: Uint8Array): { topic: string; data: T } {
+    const { topic, payload } = this.decode(binary)
+    const jsonString = new TextDecoder().decode(payload)
+    const data = JSON.parse(jsonString)
+    return { topic, data }
+  }
+}

events/EventSystem/SocketIOClientEventBus.ts

@@ -0,0 +1,42 @@
+import { Socket } from 'socket.io-client'
+import { CallbackStore } from './CallbackStore'
+import { EventBusInterface } from './EventBusInterface'
+import { Event } from '../Events'
+
+export class SocketIOClientEventBus implements EventBusInterface {
+  private socket: Socket
+  private callbacks: Array<CallbackStore> = []
+
+  constructor(socket: Socket) {
+    this.socket = socket
+  }
+
+  public subscribe<MessageType>(event: Event<MessageType>, callback: (msg: MessageType) => void) {
+    const wrappedCallback = (arg: any) => {
+      callback(arg)
+    }
+    console.log('subscribing', event.topic)
+    this.socket.on(event.topic, wrappedCallback)
+    this.callbacks.push({
+      callback,
+      wrappedCallback,
+    })
+  }
+
+  public unsubscribeAll<MessageType>(event: Event<MessageType>) {
+    this.socket.removeAllListeners(event.topic)
+  }
+
+  public unsubscribe<MessageType>(event: Event<MessageType>, callback: any) {
+    const item = this.callbacks.find(store => store.callback === callback)
+    if (!item) {
+      return
+    }
+    this.socket.off(event.topic, item.wrappedCallback)
+    this.callbacks = this.callbacks.filter(a => a !== item)
+  }
+
+  public emit<MessageType>(event: Event<MessageType>, msg: MessageType) {
+    this.socket.emit(event.topic, msg)
+  }
+}

events/EventSystem/SocketIOServerEventBus.ts

@@ -0,0 +1,274 @@
+import { Server as SocketIOServer, Socket } from 'socket.io'
+import { Event } from '../Events'
+import { EventBusInterface } from './EventBusInterface'
+import Debug from 'debug'
+
+const debug = Debug('mqtt-explorer:socketio')
+const debugConnect = Debug('mqtt-explorer:socketio:connect')
+const debugDisconnect = Debug('mqtt-explorer:socketio:disconnect')
+const debugSubscriptions = Debug('mqtt-explorer:socketio:subscriptions')
+const debugConnections = Debug('mqtt-explorer:socketio:connections')
+const debugEmit = Debug('mqtt-explorer:socketio:emit')
+
+interface SocketSubscription {
+  topic: string
+  handler: (arg: any) => void
+}
+
+export class SocketIOServerEventBus implements EventBusInterface {
+  private io: SocketIOServer
+  private clients: Map<string, Socket> = new Map() // socketId -> Socket
+
+  // Global handlers that apply to ALL sockets (like RPC endpoints)
+  private globalHandlers: Map<string, (socket: Socket, arg: any) => void> = new Map()
+
+  // Per-socket subscriptions for cleanup
+  private socketSubscriptions: Map<string, Array<SocketSubscription>> = new Map()
+
+  // Track which socket is currently processing a request
+  private currentSocket: Socket | undefined
+
+  // Map connectionId -> socketId to route messages to correct client
+  private connectionOwners: Map<string, string> = new Map()
+
+  // Track which connections to close when a socket disconnects
+  private socketConnections: Map<string, Set<string>> = new Map()
+
+  constructor(io: SocketIOServer) {
+    this.io = io
+
+    // Register connection handler once
+    this.io.on('connection', socket => {
+      debugConnect('Client connected: %s', socket.id)
+      this.clients.set(socket.id, socket)
+      this.socketSubscriptions.set(socket.id, [])
+      this.socketConnections.set(socket.id, new Set())
+
+      // Register all global handlers on this socket
+      this.globalHandlers.forEach((handler, topic) => {
+        this.registerHandlerOnSocket(socket, topic, handler)
+      })
+
+      // Log connection metrics
+      this.logConnectionMetrics('connect', socket.id)
+
+      socket.on('disconnect', () => {
+        debugDisconnect('Client disconnected: %s', socket.id)
+        this.cleanupSocket(socket)
+        this.clients.delete(socket.id)
+        this.logConnectionMetrics('disconnect', socket.id)
+      })
+    })
+  }
+
+  private logConnectionMetrics(event: 'connect' | 'disconnect', socketId: string) {
+    const totalClients = this.clients.size
+    const totalSubscriptions = Array.from(this.socketSubscriptions.values()).reduce((sum, subs) => sum + subs.length, 0)
+    const totalConnections = this.connectionOwners.size
+    const socketSubs = this.socketSubscriptions.get(socketId)?.length || 0
+    const socketConns = this.socketConnections.get(socketId)?.size || 0
+
+    debug(
+      '[%s] clients=%d subscriptions=%d mqttConns=%d | socket[%s]: subs=%d conns=%d',
+      event,
+      totalClients,
+      totalSubscriptions,
+
+      totalConnections,
+      socketId.substring(0, 8),
+      socketSubs,
+      socketConns
+    )
+
+    debugSubscriptions(
+      'Total subscriptions: %d across %d sockets (avg: %d per socket)',
+      totalSubscriptions,
+      totalClients,
+      totalClients > 0 ? Math.round(totalSubscriptions / totalClients) : 0
+    )
+
+    debugConnections(
+      'MQTT connections: %d total, %d owned by socket %s',
+      totalConnections,
+      socketConns,
+      socketId.substring(0, 8)
+    )
+  }
+
+  private registerHandlerOnSocket(socket: Socket, topic: string, handler: (socket: Socket, arg: any) => void) {
+    const wrappedHandler = (arg: any) => {
+      this.currentSocket = socket
+
+      // Track connection ownership when a connection is added
+      if (topic === 'connection/add/mqtt' && arg?.id) {
+        this.connectionOwners.set(arg.id, socket.id)
+        const socketConns = this.socketConnections.get(socket.id)
+        if (socketConns) {
+          socketConns.add(arg.id)
+        }
+        debugConnections(
+          'Connection %s owned by socket %s (total: %d)',
+          arg.id,
+          socket.id.substring(0, 8),
+          socketConns?.size || 0
+        )
+      }
+
+      // Remove connection ownership when a connection is removed
+      if (topic === 'connection/remove' && typeof arg === 'string') {
+        this.connectionOwners.delete(arg)
+        const socketConns = this.socketConnections.get(socket.id)
+        if (socketConns) {
+          socketConns.delete(arg)
+        }
+        debugConnections(
+          'Connection %s removed (socket %s remaining: %d)',
+          arg,
+          socket.id.substring(0, 8),
+          socketConns?.size || 0
+        )
+      }
+
+      handler(socket, arg)
+    }
+
+    socket.on(topic, wrappedHandler)
+
+    // Track subscription for cleanup
+    const subscriptions = this.socketSubscriptions.get(socket.id)
+    if (subscriptions) {
+      subscriptions.push({ topic, handler: wrappedHandler })
+    }
+  }
+
+  private cleanupSocket(socket: Socket) {
+    debugDisconnect('Cleaning up socket %s', socket.id)
+
+    // Remove all event listeners for this socket
+    const subscriptions = this.socketSubscriptions.get(socket.id)
+    if (subscriptions) {
+      subscriptions.forEach(({ topic, handler }) => {
+        socket.off(topic, handler)
+      })
+      this.socketSubscriptions.delete(socket.id)
+      debugSubscriptions('Removed %d subscriptions for socket %s', subscriptions.length, socket.id.substring(0, 8))
+    }
+
+    // Close all MQTT connections owned by this socket
+    const ownedConnections = this.socketConnections.get(socket.id)
+    if (ownedConnections && ownedConnections.size > 0) {
+      debugConnections(
+        'Socket %s owned %d connections, requesting cleanup',
+        socket.id.substring(0, 8),
+        ownedConnections.size
+      )
+
+      // Emit connection/remove for each owned connection
+      // This will be handled by ConnectionManager to actually close the MQTT connection
+      ownedConnections.forEach(connectionId => {
+        debugConnections('Auto-closing connection %s (owner disconnected)', connectionId)
+        // Simulate a remove request from this socket
+        const removeHandler = this.globalHandlers.get('connection/remove')
+        if (removeHandler) {
+          this.currentSocket = socket
+          removeHandler(socket, connectionId)
+        }
+        this.connectionOwners.delete(connectionId)
+      })
+
+      this.socketConnections.delete(socket.id)
+    }
+
+    // Remove from clients set
+    this.clients.delete(socket.id)
+
+    // Clear current socket if it was this one
+    if (this.currentSocket === socket) {
+      this.currentSocket = undefined
+    }
+
+    debugDisconnect('Cleanup complete for socket %s', socket.id.substring(0, 8))
+  }
+
+  public subscribe<MessageType>(subscribeEvent: Event<MessageType>, callback: (msg: MessageType) => void) {
+    const handler = (socket: Socket, arg: any) => {
+      this.currentSocket = socket
+      callback(arg)
+    }
+
+    // Store as global handler
+    this.globalHandlers.set(subscribeEvent.topic, handler)
+
+    // Register on all currently connected clients
+    this.clients.forEach(client => {
+      this.registerHandlerOnSocket(client, subscribeEvent.topic, handler)
+    })
+  }
+
+  public unsubscribeAll<MessageType>(event: Event<MessageType>) {
+    // Remove from global handlers
+    this.globalHandlers.delete(event.topic)
+
+    // Remove from all sockets
+    this.clients.forEach(client => {
+      const subscriptions = this.socketSubscriptions.get(client.id)
+      if (subscriptions) {
+        const toRemove = subscriptions.filter(s => s.topic === event.topic)
+        toRemove.forEach(({ handler }) => {
+          client.off(event.topic, handler)
+        })
+
+        // Update subscriptions list
+        this.socketSubscriptions.set(
+          client.id,
+          subscriptions.filter(s => s.topic !== event.topic)
+        )
+      }
+    })
+  }
+
+  public unsubscribe<MessageType>(event: Event<MessageType>, callback: any) {
+    throw new Error('Not implemented - use unsubscribeAll instead')
+  }
+
+  public emit<MessageType>(event: Event<MessageType>, msg: MessageType) {
+    const topic = event.topic
+
+    // Check if this is an RPC response (contains /response/ in topic)
+    if (topic.includes('/response/')) {
+      if (this.currentSocket && this.currentSocket.connected) {
+        this.currentSocket.emit(topic, msg)
+      }
+      return
+    }
+
+    // Check if this is a connection-specific event - optimized with early pattern match
+    // Patterns: conn/${connectionId}, conn/state/${connectionId}, conn/publish/${connectionId}
+    if (topic.startsWith('conn/')) {
+      const parts = topic.split('/')
+      let connectionId: string | undefined
+
+      if (parts.length === 2) {
+        // conn/${connectionId}
+        connectionId = parts[1]
+      } else if (parts.length === 3 && (parts[1] === 'state' || parts[1] === 'publish')) {
+        // conn/state/${connectionId} or conn/publish/${connectionId}
+        connectionId = parts[2]
+      }
+
+      if (connectionId) {
+        const ownerSocketId = this.connectionOwners.get(connectionId)
+        if (ownerSocketId) {
+          const ownerSocket = this.clients.get(ownerSocketId)
+          if (ownerSocket && ownerSocket.connected) {
+            ownerSocket.emit(topic, msg)
+            return
+          }
+        }
+      }
+    }
+
+    // All other events go to all clients
+    this.io.emit(topic, msg)
+  }
+}

events/Events.ts

@@ -1,4 +1,4 @@
-import { Base64Message } from '../backend/src/Model/Base64Message'
+import { Base64MessageDTO } from '../backend/src/Model/Base64Message'
 import { DataSourceState, MqttOptions } from '../backend/src/DataSource'
 import { UpdateInfo } from 'builder-util-runtime'
 import { RpcEvent } from './EventSystem/Rpc'
@@ -32,7 +32,7 @@ export const updateAvailable: Event<UpdateInfo> = {
 
 export interface MqttMessage {
   topic: string
-  payload: Base64Message | null
+  payload: Base64MessageDTO | null
   qos: 0 | 1 | 2
   retain: boolean
   // Set if QoS is > 0 on received messages
@@ -54,3 +54,11 @@ export function makeConnectionMessageEvent(connectionId: string): Event<MqttMess
 export const getAppVersion: RpcEvent<void, string> = {
   topic: 'getAppVersion',
 }
+
+export const writeToFile: RpcEvent<{ filePath: string; data: string; encoding?: string }, void> = {
+  topic: 'writeFile',
+}
+
+export const readFromFile: RpcEvent<{ filePath: string; encoding?: string }, Buffer> = {
+  topic: 'readFromFile',
+}

events/EventsV2.ts

@@ -0,0 +1,71 @@
+/**
+ * Simplified Event System V2
+ *
+ * This provides a simpler, more type-safe way to define and use events.
+ * Instead of factory functions like makeConnectionStateEvent(id),
+ * you can now use: Events.connectionState(id)
+ */
+
+import { Base64MessageDTO } from '../backend/src/Model/Base64Message'
+import { DataSourceState, MqttOptions } from '../backend/src/DataSource'
+import { UpdateInfo } from 'builder-util-runtime'
+import { RpcEvent } from './EventSystem/Rpc'
+
+export type EventV2<MessageType> = {
+  topic: string
+}
+
+// Simple event definitions (no parameters)
+export const Events = {
+  // Connection management
+  addMqttConnection: { topic: 'connection/add/mqtt' } as EventV2<AddMqttConnectionV2>,
+  removeConnection: { topic: 'connection/remove' } as EventV2<string>,
+  updateAvailable: { topic: 'app/update/available' } as EventV2<UpdateInfo>,
+
+  // Parameterized events (for connection-specific events)
+  connectionState: (connectionId: string) => ({ topic: `conn/state/${connectionId}` }) as EventV2<DataSourceState>,
+  connectionMessage: (connectionId: string) => ({ topic: `conn/${connectionId}` }) as EventV2<MqttMessageV2>,
+  publish: (connectionId: string) => ({ topic: `conn/publish/${connectionId}` }) as EventV2<MqttMessageV2>,
+}
+
+// RPC Events - type-safe request/response patterns
+export const RpcEvents = {
+  getAppVersion: { topic: 'getAppVersion' } as RpcEvent<void, string>,
+  writeToFile: { topic: 'writeFile' } as RpcEvent<{ filePath: string; data: string; encoding?: string }, void>,
+  readFromFile: { topic: 'readFromFile' } as RpcEvent<{ filePath: string; encoding?: string }, Buffer>,
+  openDialog: { topic: 'openDialog' } as RpcEvent<OpenDialogOptionsV2, OpenDialogReturnValueV2>,
+  saveDialog: { topic: 'saveDialog' } as RpcEvent<SaveDialogOptionsV2, SaveDialogReturnValueV2>,
+  uploadCertificate: { topic: 'uploadCertificate' } as RpcEvent<CertificateUploadRequest, CertificateUploadResponse>,
+}
+
+// Type definitions
+export interface AddMqttConnectionV2 {
+  id: string
+  options: MqttOptions
+}
+
+export interface MqttMessageV2 {
+  topic: string
+  payload: Base64MessageDTO | null
+  qos: 0 | 1 | 2
+  retain: boolean
+  messageId: number | undefined
+}
+
+export interface CertificateUploadRequest {
+  filename: string
+  data: string // base64 encoded
+}
+
+export interface CertificateUploadResponse {
+  name: string
+  data: string // base64 encoded
+}
+
+// Electron dialog types (re-exported for convenience)
+import { OpenDialogOptions, OpenDialogReturnValue, SaveDialogOptions, SaveDialogReturnValue } from 'electron'
+
+export type OpenDialogOptionsV2 = OpenDialogOptions
+export type OpenDialogReturnValueV2 = OpenDialogReturnValue
+export type SaveDialogOptionsV2 = SaveDialogOptions
+export type SaveDialogReturnValueV2 = SaveDialogReturnValue

events/OpenDialogRequest.ts

@@ -1,8 +1,15 @@
-import { OpenDialogOptions, OpenDialogReturnValue } from 'electron'
+import { OpenDialogOptions, OpenDialogReturnValue, SaveDialogOptions, SaveDialogReturnValue } from 'electron'
 import { RpcEvent } from './EventSystem/Rpc'
 
+// Legacy functions - use RpcEvents from EventsV2.ts for new code
 export function makeOpenDialogRpc(): RpcEvent<OpenDialogOptions, OpenDialogReturnValue> {
   return {
     topic: 'openDialog',
   }
 }
+
+export function makeSaveDialogRpc(): RpcEvent<SaveDialogOptions, SaveDialogReturnValue> {
+  return {
+    topic: 'saveDialog',
+  }
+}

events/index.ts

@@ -1,4 +1,5 @@
 export * from './Events'
+export * from './EventsV2'
 export * from './EventSystem/EventDispatcher'
 export * from './EventSystem/EventBus'
 export * from './EventSystem/EventBusInterface'

mcp.json

@@ -0,0 +1,14 @@
+{
+  "mcpServers": {
+    "playwright": {
+      "command": "npx",
+      "args": [
+        "-y",
+        "@modelcontextprotocol/server-playwright"
+      ],
+      "env": {
+        "PLAYWRIGHT_BROWSERS_PATH": "0"
+      }
+    }
+  }
+}

package.json

@@ -4,18 +4,24 @@
   "description": "Explore your message queues",
   "main": "dist/src/electron.js",
   "engines": {
-    "node": ">=18"
+    "node": ">=20"
   },
   "private": "true",
   "scripts": {
     "start": "electron .",
+    "start:server": "npx tsc && node dist/src/server.js",
     "test": "yarn test:app && yarn test:backend",
     "test:app": "cd app && yarn test",
     "test:backend": "cd backend && yarn test",
+    "test:ui": "tsc && mocha --require source-map-support/register dist/src/spec/ui-tests.spec.js",
+    "test:mcp": "tsc && node dist/src/spec/testMcpIntrospection.js",
     "install": "cd app && yarn && cd ..",
     "dev": "npm-run-all --parallel dev:*",
     "dev:app": "cd app && npm run dev",
     "dev:electron": "tsc && electron . --development",
+    "dev:server": "npm-run-all --parallel dev:server:*",
+    "dev:server:app": "cd app && npx webpack-dev-server --config webpack.browser.config.js --mode development --progress",
+    "dev:server:backend": "tsc && node dist/src/server.js",
     "lint": "npm-run-all --parallel lint:prettier lint:tslint lint:spellcheck",
     "lint:fix": "npm-run-all lint:tslint:fix lint:prettier:fix",
     "lint:prettier": "prettier --check \"**/*.ts{x,}\"",
@@ -24,6 +30,7 @@
     "lint:tslint:fix": "tslint -p ./ --fix",
     "lint:spellcheck": "cspell -e ./build -e \"node_modules\" \"**/*.ts{x,}\"",
     "build": "tsc && cd app && yarn run build && cd ..",
+    "build:server": "npx tsc && cd app && npx webpack --config webpack.browser.config.js --mode production && cd ..",
     "prepare-release": "ts-node scripts/prepare-release.ts",
     "package": "ts-node package.ts",
     "ui-test": "./scripts/uiTests.sh",
@@ -82,20 +89,23 @@
     "@semantic-release/changelog": "^6.0.3",
     "@semantic-release/commit-analyzer": "^12.0.0",
     "@semantic-release/git": "^10.0.1",
+    "@types/bcryptjs": "^3.0.0",
     "@types/chai": "^4.1.7",
+    "@types/express": "^5.0.6",
     "@types/fs-extra": "8",
     "@types/lowdb": "^1.0.6",
     "@types/mime": "^2.0.0",
     "@types/mocha": "^7.0.2",
     "@types/mustache": "4",
-    "@types/node": "^12.6.8",
+    "@types/node": "^25.0.3",
     "@types/semver": "7",
     "@types/sha1": "^1.1.1",
+    "@types/socket.io": "^3.0.2",
     "@types/uuid": "^8.3.4",
     "builder-util-runtime": "^9",
     "chai": "^4.2.0",
     "cspell": "^8.6.1",
-    "electron": "29.2.0",
+    "electron": "39.2.7",
     "electron-builder": "^24.13.3",
     "mocha": "^10.4.0",
     "mustache": "4",
@@ -118,16 +128,21 @@
   "dependencies": {
     "about-window": "^1.12.1",
     "axios": "^0.28.0",
+    "bcryptjs": "^3.0.3",
+    "debug": "^4.3.4",
     "dot-prop": "^5.0.0",
     "electron-log": "4.4.6",
     "electron-updater": "^4.6",
+    "express": "^5.2.1",
     "fs-extra": "9",
     "js-base64": "^3.7.2",
     "json-to-ast": "^2.1.0",
     "lowdb": "^1.0.0",
     "mime": "^2.4.4",
     "mqtt": "^4.3.6",
+    "protobufjs": "^8.0.0",
     "sha1": "^1.1.1",
+    "socket.io": "^4.8.1",
     "sparkplug-payload": "^1.0.3",
     "uuid": "^8.3.2",
     "yarn-run-all": "^3.1.1"

scripts/runUiTests.sh

@@ -0,0 +1,39 @@
+#!/bin/bash
+set -e
+
+function finish {
+  set +e
+  echo "Exiting, cleaning up.."
+
+  if [[ ! -z "$PID_MOSQUITTO" ]]; then
+    echo "Stopping mosquitto ($PID_MOSQUITTO).."
+    kill "$PID_MOSQUITTO" || echo "Already stopped"
+  fi
+
+  if [[ ! -z "$PID_XVFB" ]]; then
+    echo "Stopping XVFB ($PID_XVFB).."
+    kill "$PID_XVFB" || echo "Already stopped"
+  fi
+}
+
+trap finish EXIT
+
+DIMENSIONS="1024x720"
+SCR=99
+
+# Start new window manager
+Xvfb :$SCR -screen 0 "$DIMENSIONS"x24 -ac &
+export PID_XVFB=$!
+sleep 2
+
+# Start mqtt broker
+mosquitto &
+export PID_MOSQUITTO=$!
+sleep 1
+
+# Run UI tests
+DISPLAY=:$SCR yarn test:ui
+TEST_EXIT_CODE=$?
+
+echo "UI tests exited with $TEST_EXIT_CODE"
+exit $TEST_EXIT_CODE

src/AuthManager.ts

@@ -0,0 +1,94 @@
+import * as fs from 'fs'
+import * as path from 'path'
+import * as bcrypt from 'bcryptjs'
+import { v4 as uuidv4 } from 'uuid'
+
+export interface Credentials {
+  username: string
+  passwordHash: string
+}
+
+export class AuthManager {
+  private credentialsPath: string
+  private credentials: Credentials | undefined
+
+  constructor(credentialsPath: string) {
+    this.credentialsPath = credentialsPath
+  }
+
+  public async initialize(): Promise<void> {
+    // Try to get credentials from environment variables
+    const envUsername = process.env.MQTT_EXPLORER_USERNAME
+    const envPassword = process.env.MQTT_EXPLORER_PASSWORD
+
+    if (envUsername && envPassword) {
+      // Use environment credentials
+      console.log('Using credentials from environment variables')
+      console.log('Username:', envUsername)
+      this.credentials = {
+        username: envUsername,
+        passwordHash: await bcrypt.hash(envPassword, 10),
+      }
+      return
+    }
+
+    // Try to load from file
+    if (fs.existsSync(this.credentialsPath)) {
+      try {
+        const data = fs.readFileSync(this.credentialsPath, 'utf8')
+        this.credentials = JSON.parse(data)
+        console.log('Loaded credentials from', this.credentialsPath)
+        console.log('Username:', this.credentials!.username)
+        return
+      } catch (error) {
+        console.error('Failed to load credentials from file:', error)
+      }
+    }
+
+    // Generate new credentials
+    const username = `user-${uuidv4().substring(0, 8)}`
+    const password = uuidv4()
+
+    console.log('='.repeat(60))
+    console.log('Generated new credentials:')
+    console.log('Username:', username)
+    console.log('Password:', password)
+    console.log('='.repeat(60))
+    console.log('Please save these credentials. They will be persisted to:')
+    console.log(this.credentialsPath)
+    console.log('='.repeat(60))
+
+    this.credentials = {
+      username,
+      passwordHash: await bcrypt.hash(password, 10),
+    }
+
+    // Save to file
+    try {
+      const dir = path.dirname(this.credentialsPath)
+      if (!fs.existsSync(dir)) {
+        fs.mkdirSync(dir, { recursive: true })
+      }
+      fs.writeFileSync(this.credentialsPath, JSON.stringify(this.credentials, null, 2))
+      console.log('Credentials saved successfully')
+    } catch (error) {
+      console.error('Failed to save credentials:', error)
+    }
+  }
+
+  public async verifyCredentials(username: string, password: string): Promise<boolean> {
+    if (!this.credentials) {
+      return false
+    }
+
+    if (username !== this.credentials.username) {
+      return false
+    }
+
+    return bcrypt.compare(password, this.credentials.passwordHash)
+  }
+
+  public getUsername(): string | undefined {
+    return this.credentials?.username
+  }
+}

src/development.ts

@@ -32,3 +32,22 @@ export function isDev() {
 export function runningUiTestOnCi() {
   return Boolean(process.argv.find(arg => arg === '--runningUiTestOnCi'))
 }
+
+export function enableMcpIntrospection() {
+  return Boolean(process.argv.find(arg => arg === '--enable-mcp-introspection'))
+}
+
+export function getRemoteDebuggingPort() {
+  const portArg = process.argv.find(arg => arg.startsWith('--remote-debugging-port='))
+  if (portArg) {
+    const parts = portArg.split('=')
+    if (parts.length === 2 && parts[1]) {
+      const port = parseInt(parts[1], 10)
+      // Return the port only if it's a valid number between 1 and 65535
+      if (!isNaN(port) && port > 0 && port <= 65535) {
+        return port
+      }
+    }
+  }
+  return enableMcpIntrospection() ? 9222 : undefined
+}

src/electron.ts

@@ -4,14 +4,23 @@ import ConfigStorage from '../backend/src/ConfigStorage'
 import { app, BrowserWindow, Menu, dialog } from 'electron'
 import { autoUpdater } from 'electron-updater'
 import { ConnectionManager } from '../backend/src/index'
+import { promises as fsPromise } from 'fs'
 // import { electronTelemetryFactory } from 'electron-telemetry'
 import { menuTemplate } from './MenuTemplate'
 import buildOptions from './buildOptions'
-import { waitForDevServer, isDev, runningUiTestOnCi, loadDevTools } from './development'
+import {
+  waitForDevServer,
+  isDev,
+  runningUiTestOnCi,
+  loadDevTools,
+  enableMcpIntrospection,
+  getRemoteDebuggingPort,
+} from './development'
 import { shouldAutoUpdate, handleAutoUpdate } from './autoUpdater'
 import { registerCrashReporter } from './registerCrashReporter'
-import { makeOpenDialogRpc } from '../events/OpenDialogRequest'
-import { backendRpc, getAppVersion } from '../events'
+import { makeOpenDialogRpc, makeSaveDialogRpc } from '../events/OpenDialogRequest'
+import { backendRpc, backendEvents, getAppVersion, writeToFile, readFromFile } from '../events'
+import { RpcEvents } from '../events/EventsV2'
 
 registerCrashReporter()
 
@@ -19,21 +28,57 @@ registerCrashReporter()
 //   const electronTelemetry = electronTelemetryFactory('9b0c8ca04a361eb8160d98c5', buildOptions)
 // }
 
-app.commandLine.appendSwitch('--no-sandbox')
+// disable-dev-shm-usage is required to run the debug console
+app.commandLine.appendSwitch('--no-sandbox --disable-dev-shm-usage')
+
+// Enable remote debugging for MCP introspection
+const remoteDebuggingPort = getRemoteDebuggingPort()
+if (remoteDebuggingPort) {
+  app.commandLine.appendSwitch('--remote-debugging-port', remoteDebuggingPort.toString())
+  log.info(`Remote debugging enabled on port ${remoteDebuggingPort}`)
+}
+
 app.whenReady().then(() => {
   backendRpc.on(makeOpenDialogRpc(), async request => {
     return dialog.showOpenDialog(BrowserWindow.getFocusedWindow() ?? BrowserWindow.getAllWindows()[0], request)
   })
+
+  backendRpc.on(makeSaveDialogRpc(), async request => {
+    return dialog.showSaveDialog(BrowserWindow.getFocusedWindow() ?? BrowserWindow.getAllWindows()[0], request)
+  })
+
   backendRpc.on(getAppVersion, async () => app.getVersion())
+
+  backendRpc.on(writeToFile, async ({ filePath, data, encoding }) => {
+    await fsPromise.writeFile(filePath, Buffer.from(data, 'base64'), { encoding: encoding as BufferEncoding })
+  })
+
+  backendRpc.on(readFromFile, async ({ filePath, encoding }) => {
+    if (encoding) {
+      const content = await fsPromise.readFile(filePath, { encoding: encoding as BufferEncoding })
+      return Buffer.from(content)
+    }
+    return fsPromise.readFile(filePath)
+  })
+
+  // Certificate upload handler - works for both Electron and browser mode via IPC
+  backendRpc.on(RpcEvents.uploadCertificate, async ({ filename, data }) => {
+    // In Electron, we just return the data as-is since it's already read
+    // The client will use it directly
+    return {
+      name: filename,
+      data,
+    }
+  })
 })
 
 autoUpdater.logger = log
 log.info('App starting...')
 
-const connectionManager = new ConnectionManager()
+const connectionManager = new ConnectionManager(backendEvents)
 connectionManager.manageConnections()
 
-const configStorage = new ConfigStorage(path.join(app.getPath('userData'), 'settings.json'))
+const configStorage = new ConfigStorage(path.join(app.getPath('userData'), 'settings.json'), backendRpc)
 configStorage.init()
 
 // Keep a global reference of the window object, if you don't, the window will
@@ -69,8 +114,6 @@ async function createWindow() {
     }
   })
 
-  console.log('icon path', iconPath)
-
   // Load the index.html of the app.
   if (isDev()) {
     mainWindow.loadURL('http://localhost:8080')

src/server.ts

@@ -0,0 +1,177 @@
+import express from 'express'
+import * as http from 'http'
+import * as path from 'path'
+import { Server } from 'socket.io'
+import { promises as fsPromise } from 'fs'
+import { Request, Response } from 'express'
+import { AuthManager } from './AuthManager'
+import { ConnectionManager } from '../backend/src/index'
+import ConfigStorage from '../backend/src/ConfigStorage'
+import { SocketIOServerEventBus } from '../events/EventSystem/SocketIOServerEventBus'
+import { Rpc } from '../events/EventSystem/Rpc'
+import { makeOpenDialogRpc, makeSaveDialogRpc } from '../events/OpenDialogRequest'
+import { getAppVersion, writeToFile, readFromFile } from '../events'
+import { RpcEvents } from '../events/EventsV2'
+
+const PORT = process.env.PORT || 3000
+const CREDENTIALS_PATH = path.join(process.cwd(), 'data', 'credentials.json')
+
+async function startServer() {
+  // Initialize authentication
+  const authManager = new AuthManager(CREDENTIALS_PATH)
+  await authManager.initialize()
+
+  // Create Express app
+  const app = express()
+  const server = http.createServer(app)
+  const io = new Server(server, {
+    cors: {
+      origin: '*',
+      methods: ['GET', 'POST'],
+    },
+    allowEIO3: true, // Allow Engine.IO v3 clients (backwards compatibility)
+    transports: ['websocket', 'polling'], // Support both transports
+    pingTimeout: 60000, // Increase ping timeout
+    pingInterval: 25000, // Ping interval
+  })
+
+  // Authentication middleware for Socket.io
+  io.use(async (socket, next) => {
+    const { username, password } = socket.handshake.auth
+
+    if (!username || !password) {
+      return next(new Error('Authentication required'))
+    }
+
+    const isValid = await authManager.verifyCredentials(username, password)
+    if (!isValid) {
+      return next(new Error('Invalid credentials'))
+    }
+
+    console.log('Client authenticated:', username)
+    next()
+  })
+
+  // Initialize backend event bus with Socket.io
+  const backendEvents = new SocketIOServerEventBus(io)
+  const backendRpc = new Rpc(backendEvents)
+
+  // Initialize connection manager
+  const connectionManager = new ConnectionManager(backendEvents)
+  connectionManager.manageConnections()
+
+  // Initialize config storage
+  const configStorage = new ConfigStorage(path.join(process.cwd(), 'data', 'settings.json'), backendRpc)
+  configStorage.init()
+
+  // Setup RPC handlers for file operations
+  backendRpc.on(makeOpenDialogRpc(), async request => {
+    // In browser mode, file selection is handled client-side via upload
+    // Return empty result as this will be handled differently
+    return { canceled: true, filePaths: [] }
+  })
+
+  backendRpc.on(makeSaveDialogRpc(), async request => {
+    // In browser mode, file saving is handled client-side via download
+    return { canceled: true, filePath: '' }
+  })
+
+  backendRpc.on(getAppVersion, async () => {
+    // Return version from package.json
+    try {
+      const packageJsonPath = path.join(__dirname, '..', '..', 'package.json')
+      const packageJsonData = await fsPromise.readFile(packageJsonPath, 'utf8')
+      const packageJson = JSON.parse(packageJsonData)
+      return packageJson.version
+    } catch (e) {
+      return '0.0.0'
+    }
+  })
+
+  backendRpc.on(writeToFile, async ({ filePath, data, encoding }) => {
+    // In browser mode, we store files in the server's data directory
+    const dataDir = path.join(process.cwd(), 'data', 'uploads')
+    const safePath = path.join(dataDir, path.basename(filePath))
+
+    try {
+      await fsPromise.mkdir(dataDir, { recursive: true })
+      if (encoding) {
+        await fsPromise.writeFile(safePath, Buffer.from(data, 'base64'), { encoding: encoding as BufferEncoding })
+      } else {
+        await fsPromise.writeFile(safePath, Buffer.from(data, 'base64'))
+      }
+    } catch (error) {
+      console.error('Error writing file:', error)
+      throw error
+    }
+  })
+
+  backendRpc.on(readFromFile, async ({ filePath, encoding }) => {
+    // In browser mode, files are read from the server's data directory
+    const dataDir = path.join(process.cwd(), 'data', 'uploads')
+    const safePath = path.join(dataDir, path.basename(filePath))
+
+    try {
+      if (encoding) {
+        const content = await fsPromise.readFile(safePath, { encoding: encoding as BufferEncoding })
+        return Buffer.from(content)
+      }
+      return await fsPromise.readFile(safePath)
+    } catch (error) {
+      console.error('Error reading file:', error)
+      throw error
+    }
+  })
+
+  // Certificate upload handler - via IPC for consistency
+  backendRpc.on(RpcEvents.uploadCertificate, async ({ filename, data }) => {
+    // Store certificate on server for browser mode
+    const dataDir = path.join(process.cwd(), 'data', 'certificates')
+    await fsPromise.mkdir(dataDir, { recursive: true })
+
+    const safePath = path.join(dataDir, path.basename(filename))
+    await fsPromise.writeFile(safePath, Buffer.from(data, 'base64'))
+
+    console.log('Certificate uploaded:', filename)
+
+    // Return the certificate data for client to use
+    return {
+      name: filename,
+      data,
+    }
+  })
+
+  // Serve static files
+  app.use(express.static(path.join(__dirname, '..', '..', 'app', 'build')))
+
+  // Serve index.html for all other routes (SPA)
+  app.use((req: Request, res: Response) => {
+    res.sendFile(path.join(__dirname, '..', '..', 'app', 'index.html'))
+  })
+
+  // Start server
+  server.listen(PORT, () => {
+    console.log('='.repeat(60))
+    console.log(`MQTT Explorer server running on http://localhost:${PORT}`)
+    console.log('='.repeat(60))
+  })
+
+  // Handle graceful shutdown
+  process.on('SIGTERM' as any, () => {
+    console.log('SIGTERM received, closing connections...')
+    connectionManager.closeAllConnections()
+    server.close()
+  })
+
+  process.on('SIGINT' as any, () => {
+    console.log('SIGINT received, closing connections...')
+    connectionManager.closeAllConnections()
+    server.close()
+    process.exit(0)
+  })
+}
+
+startServer().catch(error => {
+  console.error('Failed to start server:', error)
+  process.exit(1)
+})

src/spec/SceneBuilder.ts

@@ -19,6 +19,7 @@ export type SceneNames =
   | 'settings'
   | 'customize_subscriptions'
   | 'keyboard_shortcuts'
+  | 'sparkplugb-decoding'
   | 'end'
 
 export class SceneBuilder {

src/spec/demoVideo.ts

@@ -21,6 +21,7 @@ import { showMenu } from './scenarios/showMenu'
 import { showNumericPlot } from './scenarios/showNumericPlot'
 import { showOffDiffCapability } from './scenarios/showOffDiffCapability'
 import { showZoomLevel } from './scenarios/showZoomLevel'
+import { showSparkPlugDecoding } from './scenarios/showSparkplugDecoding'
 
 /**
  *  A convenience method that handles gracefully cleaning up the test run.
@@ -31,11 +32,19 @@ const cleanUp = async (scenes: SceneBuilder, electronApp: ElectronApplication) =
   await electronApp.close()
 }
 
-process.on('unhandledRejection', (error: Error | any) => {
+process.on('unhandledRejection' as any, (error: Error | any) => {
   console.error('unhandledRejection', error.message, error.stack)
   process.exit(1)
 })
 
+setTimeout(
+  () => {
+    console.error('Timeout reached')
+    process.exit(1)
+  },
+  60 * 10 * 1000
+)
+
 const runningUiTestOnCi = os.platform() === 'darwin' ? [] : ['--runningUiTestOnCi']
 
 async function doStuff() {
@@ -112,6 +121,11 @@ async function doStuff() {
     await sleep(1000)
   })
 
+  await scenes.record('sparkplugb-decoding', async () => {
+    await showText('SparkplugB Decoding', 2000, page, 'top')
+    await showSparkPlugDecoding(page)
+  })
+
   // disable this scenario for now until expandTopic is sorted out
   // await scenes.record('delete_retained_topics', async () => {
   //   await hideText(page)
@@ -143,10 +157,17 @@ async function doStuff() {
     await sleep(3000)
   })
 
+  setTimeout(() => {
+    console.log('Forced quit')
+    process.exit(0)
+  }, 10 * 1000)
   stopMqtt()
   console.log('Stopped mqtt client')
 
   cleanUp(scenes, electronApp)
+
+  // Force exit since there appear to be open handles
+  process.exit(0)
 }
 
 doStuff()

src/spec/leakTest.ts

@@ -7,7 +7,7 @@ import { clearSearch, searchTree } from './scenarios/searchTree'
 import { connectTo } from './scenarios/connect'
 import { reconnect } from './scenarios/reconnect'
 
-process.on('unhandledRejection', (error: Error | any) => {
+process.on('unhandledRejection' as any, (error: Error | any) => {
   console.error('unhandledRejection', error.message, error.stack)
   process.exit(1)
 })

src/spec/mock-mqtt-test.ts

@@ -0,0 +1,40 @@
+import * as mqtt from 'mqtt'
+
+/**
+ * Test-specific MQTT mock (no timers)
+ * 
+ * This mock connects to the broker but doesn't publish any messages automatically.
+ * Each test should publish only the messages it needs via the returned client.
+ * 
+ * This is different from the demo video mock which uses timers.
+ */
+
+let mqttClient: mqtt.MqttClient | null = null
+
+export async function createTestMock(): Promise<mqtt.MqttClient> {
+  if (mqttClient) {
+    return mqttClient
+  }
+
+  return new Promise(resolve => {
+    const client = mqtt.connect('mqtt://127.0.0.1:1883', {
+      username: '',
+      password: '',
+    })
+    client.once('connect', () => {
+      mqttClient = client
+      resolve(client)
+    })
+  })
+}
+
+export function stopTestMock() {
+  if (mqttClient) {
+    try {
+      mqttClient.end()
+      mqttClient = null
+    } catch {
+      // ignore
+    }
+  }
+}

src/spec/mock-sparkplugb.ts

@@ -18,232 +18,228 @@ import type { UMetric } from 'sparkplug-payload/lib/sparkplugbpayload'
  * Main sample function which includes the run() function for running the sample
  */
 
-
 export interface MockSparkplugClient {
-    stop: () => void
+  stop: () => void
 }
 
-var sample = (function () {
-    var config = {
-        serverUrl: 'tcp://127.0.0.1:1883',
-        username: '',
-        password: '',
-        groupId: 'Sparkplug Devices',
-        edgeNode: 'JavaScript Edge Node',
-        clientId: 'JavaScriptSimpleEdgeNode',
-        version: 'spBv1.0',
+let sample = (function () {
+  let config = {
+      serverUrl: 'tcp://127.0.0.1:1883',
+      username: '',
+      password: '',
+      groupId: 'Sparkplug Devices',
+      edgeNode: 'JavaScript Edge Node',
+      clientId: 'JavaScriptSimpleEdgeNode',
+      version: 'spBv1.0',
     },
-        hwVersion = 'Emulated Hardware',
-        swVersion = 'v1.0.0',
-        deviceId = 'Emulated Device',
-        sparkPlugClient,
-        publishPeriod = 5000,
-        // Generates a random integer
-        randomInt = function () {
-            return 1 + Math.floor(Math.random() * 10)
-        },
-        // Get BIRTH payload for the edge node
-        getNodeBirthPayload = function (): UPayload {
-            return {
-                timestamp: new Date().getTime(),
-                metrics: [
-                    {
-                        name: 'Node Control/Rebirth',
-                        type: 'Boolean',
-                        value: false,
-                    },
-                    {
-                        name: 'Template1',
-                        type: 'Template',
-                        value: {
-                            isDefinition: true,
-                            metrics: [
-                                { name: 'myBool', value: false, type: 'Boolean' },
-                                { name: 'myInt', value: 0, type: 'UInt32' },
-                            ],
-                            parameters: [
-                                {
-                                    name: 'param1',
-                                    type: 'String',
-                                    value: 'value1',
-                                },
-                            ],
-                        },
-                    },
-                ],
+    hwVersion = 'Emulated Hardware',
+    swVersion = 'v1.0.0',
+    deviceId = 'Emulated Device',
+    sparkPlugClient,
+    publishPeriod = 5000,
+    // Generates a random integer
+    randomInt = function () {
+      return 1 + Math.floor(Math.random() * 10)
+    },
+    // Get BIRTH payload for the edge node
+    getNodeBirthPayload = function (): UPayload {
+      return {
+        timestamp: new Date().getTime(),
+        metrics: [
+          {
+            name: 'Node Control/Rebirth',
+            type: 'Boolean',
+            value: false,
+          },
+          {
+            name: 'Template1',
+            type: 'Template',
+            value: {
+              isDefinition: true,
+              metrics: [
+                { name: 'myBool', value: false, type: 'Boolean' },
+                { name: 'myInt', value: 0, type: 'UInt32' },
+              ],
+              parameters: [
+                {
+                  name: 'param1',
+                  type: 'String',
+                  value: 'value1',
+                },
+              ],
+            },
+          },
+        ],
+      }
+    },
+    // Get BIRTH payload for the device
+    getDeviceBirthPayload = function (): UPayload {
+      return {
+        timestamp: new Date().getTime(),
+        metrics: [
+          { name: 'my_boolean', value: Math.random() > 0.5, type: 'Boolean' },
+          { name: 'my_double', value: Math.random() * 0.123456789, type: 'Double' },
+          { name: 'my_float', value: Math.random() * 0.123, type: 'Float' },
+          { name: 'my_int', value: randomInt(), type: 'Int8' },
+          { name: 'my_long', value: randomInt() * 214748364700, type: 'Int64' },
+          { name: 'Inputs/0', value: true, type: 'Boolean' },
+          { name: 'Inputs/1', value: 0, type: 'Int8' },
+          { name: 'Inputs/2', value: 1.23, type: 'UInt64' },
+          { name: 'Outputs/0', value: true, type: 'Boolean' },
+          { name: 'Outputs/1', value: 0, type: 'Int16' },
+          { name: 'Outputs/2', value: 1.23, type: 'UInt64' },
+          { name: 'Properties/hw_version', value: hwVersion, type: 'String' },
+          { name: 'Properties/sw_version', value: swVersion, type: 'String' },
+          {
+            name: 'my_dataset',
+            type: 'DataSet',
+            value: {
+              numOfColumns: 2,
+              types: ['String', 'String'],
+              columns: ['str1', 'str2'],
+              rows: [
+                ['x', 'a'],
+                ['y', 'b'],
+              ],
+            },
+          },
+          {
+            name: 'TemplateInstance1',
+            type: 'Template',
+            value: {
+              templateRef: 'Template1',
+              isDefinition: false,
+              metrics: [
+                { name: 'myBool', value: true, type: 'Boolean' },
+                { name: 'myInt', value: 100, type: 'Int8' },
+              ],
+              parameters: [
+                {
+                  name: 'param1',
+                  type: 'String',
+                  value: 'value2',
+                },
+              ],
+            },
+          },
+        ],
+      }
+    },
+    // Get data payload for the device
+    getDataPayload = function (): UPayload {
+      return {
+        timestamp: new Date().getTime(),
+        metrics: [
+          { name: 'my_boolean', value: Math.random() > 0.5, type: 'Boolean' },
+          { name: 'my_double', value: Math.random() * 0.123456789, type: 'Double' },
+          { name: 'my_float', value: Math.random() * 0.123, type: 'UInt64' },
+          { name: 'my_int', value: randomInt(), type: 'Int16' },
+          { name: 'my_long', value: randomInt() * 214748364700, type: 'UInt64' },
+        ],
+      }
+    },
+    // Runs the sample
+    run = async function (): Promise<MockSparkplugClient> {
+      // Create the SparkplugClient
+      const sparkplugClient = SparkplugClient.newClient(config)
+      let updateInterval: NodeJS.Timeout | null = null
+      const connected = new Promise<MockSparkplugClient>(resolve => {
+        // Create 'birth' handler
+        sparkplugClient.on('birth', () => {
+          // Publish Node BIRTH certificate
+          sparkplugClient.publishNodeBirth(getNodeBirthPayload())
+          // Publish Device BIRTH certificate
+          sparkplugClient.publishDeviceBirth(deviceId, getDeviceBirthPayload())
+          resolve({
+            stop: () => {
+              if (updateInterval) {
+                clearInterval(updateInterval)
+              }
+              sparkplugClient.stop()
+            },
+          })
+        })
+      })
+
+      // Create Incoming Message Handler
+      sparkplugClient.on('message', function (topic: string, payload: UPayload) {
+        console.log(topic, payload)
+      })
+
+      // Create node command handler
+      // spell-checker: disable-next-line
+      sparkplugClient.on('ncmd', function (payload: UPayload) {
+        let timestamp = payload.timestamp,
+          metrics = payload.metrics
+
+        if (metrics !== undefined && metrics !== null) {
+          for (let i = 0; i < metrics.length; i++) {
+            let metric = metrics[i]
+            if (metric.name == 'Node Control/Rebirth' && metric.value) {
+              console.log("Received 'Rebirth' command")
+              // Publish Node BIRTH certificate
+              sparkplugClient.publishNodeBirth(getNodeBirthPayload())
+              // Publish Device BIRTH certificate
+              sparkplugClient.publishDeviceBirth(deviceId, getDeviceBirthPayload())
             }
-        },
-        // Get BIRTH payload for the device
-        getDeviceBirthPayload = function (): UPayload {
-            return {
-                timestamp: new Date().getTime(),
-                metrics: [
-                    { name: 'my_boolean', value: Math.random() > 0.5, type: 'Boolean' },
-                    { name: 'my_double', value: Math.random() * 0.123456789, type: 'Double' },
-                    { name: 'my_float', value: Math.random() * 0.123, type: 'Float' },
-                    { name: 'my_int', value: randomInt(), type: 'Int8' },
-                    { name: 'my_long', value: randomInt() * 214748364700, type: 'Int64' },
-                    { name: 'Inputs/0', value: true, type: 'Boolean' },
-                    { name: 'Inputs/1', value: 0, type: 'Int8' },
-                    { name: 'Inputs/2', value: 1.23, type: 'UInt64' },
-                    { name: 'Outputs/0', value: true, type: 'Boolean' },
-                    { name: 'Outputs/1', value: 0, type: 'Int16' },
-                    { name: 'Outputs/2', value: 1.23, type: 'UInt64' },
-                    { name: 'Properties/hw_version', value: hwVersion, type: 'String' },
-                    { name: 'Properties/sw_version', value: swVersion, type: 'String' },
-                    {
-                        name: 'my_dataset',
-                        type: 'DataSet',
-                        value: {
-                            numOfColumns: 2,
-                            types: ['String', 'String'],
-                            columns: ['str1', 'str2'],
-                            rows: [
-                                ['x', 'a'],
-                                ['y', 'b'],
-                            ],
-                        },
-                    },
-                    {
-                        name: 'TemplateInstance1',
-                        type: 'Template',
-                        value: {
-                            templateRef: 'Template1',
-                            isDefinition: false,
-                            metrics: [
-                                { name: 'myBool', value: true, type: 'Boolean' },
-                                { name: 'myInt', value: 100, type: 'Int8' },
-                            ],
-                            parameters: [
-                                {
-                                    name: 'param1',
-                                    type: 'String',
-                                    value: 'value2',
-                                },
-                            ],
-                        },
-                    },
-                ],
+          }
+        }
+      })
+
+      // Create device command handler
+      // spell-checker: disable-next-line
+      sparkplugClient.on('dcmd', function (deviceId: string, payload: UPayload) {
+        let timestamp = payload.timestamp,
+          metrics = payload.metrics,
+          inboundMetricMap: { [name: string]: any } = {},
+          outboundMetric: Array<UMetric> = [],
+          outboundPayload: UPayload
+
+        console.log('Command received for device ' + deviceId)
+
+        // Loop over the metrics and store them in a map
+        if (metrics !== undefined && metrics !== null) {
+          for (let i = 0; i < metrics.length; i++) {
+            let metric = metrics[i]
+            if (metric.name !== undefined && metric.name !== null) {
+              inboundMetricMap[metric.name] = metric.value
             }
-        },
-        // Get data payload for the device
-        getDataPayload = function (): UPayload {
-            return {
-                timestamp: new Date().getTime(),
-                metrics: [
-                    { name: 'my_boolean', value: Math.random() > 0.5, type: 'Boolean' },
-                    { name: 'my_double', value: Math.random() * 0.123456789, type: 'Double' },
-                    { name: 'my_float', value: Math.random() * 0.123, type: 'UInt64' },
-                    { name: 'my_int', value: randomInt(), type: 'Int16' },
-                    { name: 'my_long', value: randomInt() * 214748364700, type: 'UInt64' },
-                ],
-            }
-        },
-        // Runs the sample
-        run = async function (): Promise<MockSparkplugClient> {
-            // Create the SparkplugClient
-            const sparkplugClient = SparkplugClient.newClient(config)
-            let updateInterval: NodeJS.Timeout | null = null
-            const connected = new Promise<MockSparkplugClient>((resolve) => {
-
-                // Create 'birth' handler
-                sparkplugClient.on('birth', () => {
-                    // Publish Node BIRTH certificate
-                    sparkplugClient.publishNodeBirth(getNodeBirthPayload())
-                    // Publish Device BIRTH certificate
-                    sparkplugClient.publishDeviceBirth(deviceId, getDeviceBirthPayload())
-                    resolve({
-                        stop: () => {
-                            if (updateInterval) {
-                                clearInterval(updateInterval)
-                            }
-                            sparkplugClient.stop()
-                        }
-                    })
-                })
-            })
-
-            // Create Incoming Message Handler
-            sparkplugClient.on('message', function (topic: string, payload: UPayload) {
-                console.log(topic, payload)
-            })
-
-            // Create node command handler
-            // spell-checker: disable-next-line
-            sparkplugClient.on('ncmd', function (payload: UPayload) {
-                var timestamp = payload.timestamp,
-                    metrics = payload.metrics
-
-                if (metrics !== undefined && metrics !== null) {
-                    for (var i = 0; i < metrics.length; i++) {
-                        var metric = metrics[i]
-                        if (metric.name == 'Node Control/Rebirth' && metric.value) {
-                            console.log("Received 'Rebirth' command")
-                            // Publish Node BIRTH certificate
-                            sparkplugClient.publishNodeBirth(getNodeBirthPayload())
-                            // Publish Device BIRTH certificate
-                            sparkplugClient.publishDeviceBirth(deviceId, getDeviceBirthPayload())
-                        }
-                    }
-                }
-            })
-
-            // Create device command handler
-            // spell-checker: disable-next-line
-            sparkplugClient.on('dcmd', function (deviceId: string, payload: UPayload) {
-                var timestamp = payload.timestamp,
-                    metrics = payload.metrics,
-                    inboundMetricMap: { [name: string]: any } = {},
-                    outboundMetric: Array<UMetric> = [],
-                    outboundPayload: UPayload
-
-                console.log('Command received for device ' + deviceId)
-
-                // Loop over the metrics and store them in a map
-                if (metrics !== undefined && metrics !== null) {
-                    for (var i = 0; i < metrics.length; i++) {
-                        var metric = metrics[i]
-                        if (metric.name !== undefined && metric.name !== null) {
-                            inboundMetricMap[metric.name] = metric.value
-                        }
-                    }
-                }
-                if (inboundMetricMap['Outputs/0'] !== undefined && inboundMetricMap['Outputs/0'] !== null) {
-                    console.log('Outputs/0: ' + inboundMetricMap['Outputs/0'])
-                    outboundMetric.push({ name: 'Inputs/0', value: inboundMetricMap['Outputs/0'], type: 'Boolean' })
-                    outboundMetric.push({ name: 'Outputs/0', value: inboundMetricMap['Outputs/0'], type: 'Boolean' })
-                    console.log('Updated value for Inputs/0 ' + inboundMetricMap['Outputs/0'])
-                } else if (inboundMetricMap['Outputs/1'] !== undefined && inboundMetricMap['Outputs/1'] !== null) {
-                    console.log('Outputs/1: ' + inboundMetricMap['Outputs/1'])
-                    outboundMetric.push({ name: 'Inputs/1', value: inboundMetricMap['Outputs/1'], type: 'Int32' })
-                    outboundMetric.push({ name: 'Outputs/1', value: inboundMetricMap['Outputs/1'], type: 'Int32' })
-                    console.log('Updated value for Inputs/1 ' + inboundMetricMap['Outputs/1'])
-                } else if (inboundMetricMap['Outputs/2'] !== undefined && inboundMetricMap['Outputs/2'] !== null) {
-                    console.log('Outputs/2: ' + inboundMetricMap['Outputs/2'])
-                    outboundMetric.push({ name: 'Inputs/2', value: inboundMetricMap['Outputs/2'], type: 'UInt64' })
-                    outboundMetric.push({ name: 'Outputs/2', value: inboundMetricMap['Outputs/2'], type: 'UInt64' })
-                    console.log('Updated value for Inputs/2 ' + inboundMetricMap['Outputs/2'])
-                }
-
-                outboundPayload = {
-                    timestamp: new Date().getTime(),
-                    metrics: outboundMetric,
-                }
-
-                // Publish device data
-                sparkplugClient.publishDeviceData(deviceId, outboundPayload)
-            })
-
-            updateInterval = setInterval(function () {
-                // Publish device data
-                sparkplugClient.publishDeviceData(deviceId, getDataPayload())
-
-
-            }, 2000)
-            return connected
+          }
+        }
+        if (inboundMetricMap['Outputs/0'] !== undefined && inboundMetricMap['Outputs/0'] !== null) {
+          console.log('Outputs/0: ' + inboundMetricMap['Outputs/0'])
+          outboundMetric.push({ name: 'Inputs/0', value: inboundMetricMap['Outputs/0'], type: 'Boolean' })
+          outboundMetric.push({ name: 'Outputs/0', value: inboundMetricMap['Outputs/0'], type: 'Boolean' })
+          console.log('Updated value for Inputs/0 ' + inboundMetricMap['Outputs/0'])
+        } else if (inboundMetricMap['Outputs/1'] !== undefined && inboundMetricMap['Outputs/1'] !== null) {
+          console.log('Outputs/1: ' + inboundMetricMap['Outputs/1'])
+          outboundMetric.push({ name: 'Inputs/1', value: inboundMetricMap['Outputs/1'], type: 'Int32' })
+          outboundMetric.push({ name: 'Outputs/1', value: inboundMetricMap['Outputs/1'], type: 'Int32' })
+          console.log('Updated value for Inputs/1 ' + inboundMetricMap['Outputs/1'])
+        } else if (inboundMetricMap['Outputs/2'] !== undefined && inboundMetricMap['Outputs/2'] !== null) {
+          console.log('Outputs/2: ' + inboundMetricMap['Outputs/2'])
+          outboundMetric.push({ name: 'Inputs/2', value: inboundMetricMap['Outputs/2'], type: 'UInt64' })
+          outboundMetric.push({ name: 'Outputs/2', value: inboundMetricMap['Outputs/2'], type: 'UInt64' })
+          console.log('Updated value for Inputs/2 ' + inboundMetricMap['Outputs/2'])
         }
 
-    return { run: run }
+        outboundPayload = {
+          timestamp: new Date().getTime(),
+          metrics: outboundMetric,
+        }
+
+        // Publish device data
+        sparkplugClient.publishDeviceData(deviceId, outboundPayload)
+      })
+
+      updateInterval = setInterval(function () {
+        // Publish device data
+        sparkplugClient.publishDeviceData(deviceId, getDataPayload())
+      }, 2000)
+      return connected
+    }
+
+  return { run }
 })()
 
-export default sample
+export default sample

src/spec/scenarios/copyValueToClipboard.ts

@@ -2,6 +2,6 @@ import { Page } from 'playwright'
 import { clickOn } from '../util'
 
 export async function copyValueToClipboard(browser: Page) {
-  const copyButton = await browser.locator('//span[contains(text(), "Value")]//button')
+  const copyButton = await browser.getByRole('button', { name: 'Value' }).getByRole('button').first()
   await clickOn(copyButton, 1)
 }

src/spec/scenarios/publishTopic.ts

@@ -14,7 +14,7 @@ export async function publishTopic(browser: Page) {
   const topicInput = await browser.locator('//input[contains(@value,"kitchen/lamp/state")][1]')
   await clickOn(topicInput)
   await deleteTextWithBackspaces(topicInput, 120, 5)
-  await writeText('set', topicInput, 300)
+  await writeText('set', topicInput)
 
   const payloadInput = await browser.locator('//*[contains(@class, "ace_text-input")]')
   await writeTextPayload(payloadInput, 'off')
@@ -34,5 +34,6 @@ export async function publishTopic(browser: Page) {
 }
 
 async function writeTextPayload(payloadInput: Locator, text: string) {
-  await payloadInput.fill(text)
+  await clickOn(payloadInput)
+  await writeText(text, payloadInput)
 }

src/spec/scenarios/searchTree.ts

@@ -4,7 +4,7 @@ import { clickOn, deleteTextWithBackspaces, showText, sleep, writeText } from '.
 export async function searchTree(text: string, browser: Page) {
   const searchField = await browser.locator('//input[contains(@placeholder, "Search")]')
   await clickOn(searchField, 1)
-  await writeText(text, searchField, 100)
+  await writeText(text, searchField)
   await sleep(1500)
 }
 
@@ -12,4 +12,5 @@ export async function clearSearch(browser: Page) {
   const searchField = await browser.locator('//input[contains(@placeholder, "Search")]')
   await clickOn(searchField, 1)
   await deleteTextWithBackspaces(searchField, 100)
+  await sleep(300) // Give time for search to clear and tree to rerender
 }

src/spec/scenarios/showNumericPlot.ts

@@ -1,5 +1,5 @@
 import { Page } from 'playwright'
-import { moveToCenterOfElement, clickOn, clickOnHistory, expandTopic, sleep, writeText } from '../util'
+import { moveToCenterOfElement, clickOn, clickOnHistory, expandTopic, sleep } from '../util'
 
 export async function showNumericPlot(browser: Page) {
   await expandTopic('kitchen/coffee_maker', browser)
@@ -45,12 +45,14 @@ export async function showNumericPlot(browser: Page) {
 async function valuePreviewGuttersShowChartIcon(name: string, browser: Page) {
   for (let retries = 0; retries < 2; retries += 1) {
     try {
-      return await browser.locator(`//*[contains(@data-test-type, "ShowChart")][contains(@data-test, "${name}")]`)
+      return await browser
+        .locator(`//*[contains(@data-test-type, "ShowChart")][contains(@data-test, "${name}")]`)
+        .first()
     } catch {
       // ignore
     }
   }
-  return browser.locator(`//*[contains(@data-test-type, "ShowChart")][contains(@data-test, "${name}")]`)
+  return browser.locator(`//*[contains(@data-test-type, "ShowChart")][contains(@data-test, "${name}")]`).first()
 }
 
 async function chartSettings(name: string, browser: Page) {

src/spec/scenarios/showSparkplugDecoding.ts

@@ -0,0 +1,9 @@
+import { Page } from 'playwright'
+import { expandTopic, sleep } from '../util'
+
+export async function showSparkPlugDecoding(browser: Page) {
+  // spell-checker: disable-next-line
+  await expandTopic('spBv1.0/Sparkplug Devices/DDATA/JavaScript Edge Node/Emulated Device', browser)
+  await browser.screenshot({ path: 'screen_sparkplugb_decoding.png' })
+  await sleep(1000)
+}