Chat App Notification Server

This is a serverless function for handling push notifications in the chat application. It can be deployed to Vercel to send Firebase Cloud Messaging (FCM) notifications.

Setup Instructions

1. Firebase Service Account Setup

1. Go to the Firebase Console
2. Navigate to Project Settings > Service Accounts
3. Click "Generate new private key"
4. Save the JSON file securely

2. Environment Variables for Vercel

Set the following environment variables in your Vercel project settings:

FIREBASE_TYPE=service_account
FIREBASE_PROJECT_ID=your-firebase-project-id
FIREBASE_PRIVATE_KEY_ID=your-private-key-id
FIREBASE_PRIVATE_KEY=-----BEGIN PRIVATE KEY-----\nYOUR_PRIVATE_KEY\n-----END PRIVATE KEY-----\n
FIREBASE_CLIENT_EMAIL=your-client-email@your-project.iam.gserviceaccount.com
FIREBASE_CLIENT_ID=your-client-id
FIREBASE_AUTH_URI=https://accounts.google.com/o/oauth2/auth
FIREBASE_TOKEN_URI=https://oauth2.googleapis.com/token
FIREBASE_AUTH_PROVIDER_X509_CERT_URL=https://www.googleapis.com/oauth2/v1/certs
FIREBASE_CLIENT_X509_CERT_URL=https://www.googleapis.com/robot/v1/metadata/x509/your-client-email%40your-project.iam.gserviceaccount.com

3. Deploy to Vercel

1. Install Vercel CLI:

   npm install -g vercel

2. Deploy the project:

   vercel --prod

4. Update Flutter App

Update your Flutter app to use the deployed Vercel URL by setting the environment variable:

flutter run --dart-define=NOTIFICATION_SERVER_URL=https://your-deployment-url.vercel.app

Or for production builds:

flutter build --dart-define=NOTIFICATION_SERVER_URL=https://your-deployment-url.vercel.app

API Endpoint

POST /api/send-notification

Request Body

{
  "userId": "recipient-user-id",
  "title": "Notification Title",
  "body": "Notification Body",
  "data": {
    "key": "value"
  }
}

Response

{
  "success": true,
  "message": "Notification sent successfully",
  "response": "Firebase message ID"
}

Local Development

1. Create a .env.local file with your Firebase service account credentials
2. Run the development server:

   vercel dev

Error Handling

The server handles various error cases:

• Missing required fields
• User not found
• Invalid or expired FCM tokens
• Firebase messaging errors