Air Quality Monitoring App

An application for reading air quality data from SDS011/SDS021 particulate matter sensors via USB serial connection.

Recent Code Improvements

We've significantly improved the codebase through several key changes:

1. Simplified and Organized Sensor Utilities (sensorUtils.ts)

• Organized by Functionality: Grouped related functions into logical namespaces:

  • ByteUtils: Hex/decimal conversion utilities
  • SensorPacket: Packet handling and parsing functions
  • SensorCommands: Command generation
  • AirQualityIndex: Air quality categorization

• Removed Debug Code: Eliminated excessive console.log statements to improve readability and performance

• Better Structure: Improved organization makes the code more maintainable and easier to understand

2. Enhanced USB Serial Hook (useUsbSerial.ts)

• Consolidated State Management:

  • Combined related state variables into structured objects
  • Better organization of connection state, config options, and timers

• Improved Type Safety:

  • Added proper TypeScript interfaces for all data structures
  • Fixed issues with dynamic function references

• Reliable Connection Handling:

  • Better handling of device attachment/detachment
  • More robust error recovery mechanisms

3. Simplified Sensor Data Processing (useSensorData.ts and SensorData.tsx)

• Updated to Use New Utilities:

  • Leveraging the restructured utility functions
  • Type-safe access to style properties

• Reduced Code Duplication:

  • Eliminated redundant conversion code
  • Centralized sensor data processing logic

Benefits of These Changes

• More maintainable code: Better organization makes the code easier to understand and modify
• Reduced duplication: Common functions are defined once and reused
• Improved reliability: More robust error handling and device connection management
• Better type safety: Proper TypeScript typing throughout the codebase

Usage

Connect your SDS011/SDS021 sensor to your Android device via USB (requires OTG support). The app will automatically detect and connect to the sensor and begin displaying air quality measurements.

• PM2.5: Fine particulate matter (2.5 micrometers or smaller)
• PM10: Coarse particulate matter (10 micrometers or smaller)

The readings are color-coded according to standard air quality categories from Good (green) to Hazardous (dark pink).

Features

• Connect to SDS011/SDS021 particulate matter sensors via USB
• Real-time monitoring of PM2.5 and PM10 air quality data
• Running averages of air quality measurements
• Device discovery and connection management
• Logs with user-friendly and developer modes
• Cross-platform support for Android and iOS

Development

Prerequisites

• Node.js (v18 or higher)
• React Native CLI
• Android Studio or Xcode (depending on target platform)
• SDS011 or SDS021 PM sensor (for testing)

Getting Started

1. Install dependencies:

   npm install

2. Start the Metro server:

   npm start

3. Run the app:

   # For Android
   npm run android
   
   # For iOS
   npm run ios

Building Release Versions

Environment Setup

1. Make sure you have a keystore file in android/app/my-release-key.keystore

   • If you need to generate a keystore, run:

     keytool -genkeypair -v -storetype PKCS12 -keystore my-release-key.keystore -alias my-key-alias -keyalg RSA -keysize 2048 -validity 10000

   • Then move the generated file to android/app/
   • Important: The key alias must be exactly my-key-alias as configured in the app's build.gradle

2. Create a .env file in the project root with your keystore passwords:

   ANDROID_STORE_PASSWORD=your-store-password
   ANDROID_KEY_PASSWORD=your-key-password
   

Android Release Build

Run the following command to build a signed APK:

npm run build-android-release

The generated APK will be located at android/app/build/outputs/apk/release/app-release.apk

iOS Release Build

To build for iOS in release configuration:

npm run build-ios-release

Combined Build

To build for both platforms:

npm run build-release

Automated Builds with GitHub Actions

This project includes a GitHub Actions workflow that automatically builds and publishes Android APKs when a new version tag is pushed.

Setup

1. Add the following secrets to your GitHub repository:

   • KEYSTORE_BASE64: Your base64-encoded keystore file
   • ANDROID_STORE_PASSWORD: The password for your keystore
   • ANDROID_KEY_PASSWORD: The password for your key alias

2. Convert your keystore to base64:

   # On Linux/macOS
   base64 -i my-release-key.keystore
   
   # On Windows PowerShell
   [Convert]::ToBase64String([IO.File]::ReadAllBytes("my-release-key.keystore"))

3. Push a version tag to trigger a build:

   git tag v1.0.0
   git push origin v1.0.0

The workflow will:

1. Build the APK with release signing
2. Create a GitHub release for the tag
3. Attach the APK to the release

Building Android Release with Environment Variables

Using .env file (recommended for local development)

1. Create a .env file in the project root with your keystore passwords:

   ANDROID_STORE_PASSWORD=your_store_password
   ANDROID_KEY_PASSWORD=your_key_password
   

2. Make sure your keystore file is placed at android/app/my-release-key.keystore

3. Run the build command with environment variables loaded from .env:

   npm run build-android-release-env
   

Alternative methods

You can also provide environment variables directly:

# Windows PowerShell
$env:ANDROID_STORE_PASSWORD="your_password"
$env:ANDROID_KEY_PASSWORD="your_password"
npm run build-android-release

# Windows CMD
set ANDROID_STORE_PASSWORD=your_password
set ANDROID_KEY_PASSWORD=your_password
npm run build-android-release

# Linux/macOS
ANDROID_STORE_PASSWORD=your_password ANDROID_KEY_PASSWORD=your_password npm run build-android-release