📲 Push Notification System with Firebase and Azure

This project demonstrates a real-world implementation of push notification systems using both Azure Push Notification and Firebase Cloud Messaging (FCM). It is designed to help developers integrate push notifications seamlessly into their applications.

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🚀 Features

• Azure Push Notification Integration: Send notifications to devices using Azure Notification Hubs.
• Firebase Cloud Messaging (FCM): Leverage Firebase for scalable, cross-platform notifications.
• Firestore Database Support: Store and retrieve notification data using Google Firestore.
• Dependency Injection (DI): Clean architecture with reusable services and repositories.
• Swagger Integration: Explore and test APIs directly in your browser.
• Flexible Configuration: Easily switch between Azure and Firebase.

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📦 Technologies Used

• .NET 6 for building the backend.
• Firebase Admin SDK for FCM integration.
• Google Firestore for database operations.
• Azure Notification Hubs for sending notifications.
• Swagger for API documentation and testing.
• Dependency Injection for modular and testable architecture.

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⚙️ Installation

Prerequisites

1. .NET SDK 6 or later
   Download and install from here.

2. Google Service Account JSON
   Generate a service account JSON key from the Firebase console under "Project Settings > Service Accounts." Save this file for use in the app configuration.

3. Azure Notification Hub Connection String
   Create a notification hub in Azure and copy the connection string.

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Steps to Run

1. Clone the repository

   git clone push-notification-example
   cd push-notification-example
   

2. Restore dependencies

   dotnet restore
   

3. Configure the application
   Update the appsettings.json file with the following:

   • Firebase JSON Credential:

     "GoogleCredential": {
         "type": "service_account",
         "project_id": "your-project-id",
         "private_key_id": "your-private-key-id",
         "private_key": "your-private-key",
         "client_email": "your-client-email",
         "client_id": "your-client-id",
         "auth_uri": "https://accounts.google.com/o/oauth2/auth",
         "token_uri": "https://oauth2.googleapis.com/token",
         "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
         "client_x509_cert_url": "your-cert-url"
     }

   • Azure Notification Hub:

     "NotificationHubOptions": {
         "ConnectionString": "your-azure-connection-string",
         "HubName": "your-notification-hub-name"
     }

4. Run the application
   Start the application:

   dotnet run
   

5. Access the Swagger UI
   Navigate to https://localhost:5001/swagger to explore and test the APIs.

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🛠️ Usage

Azure Push Notifications

• Inject and use the IAzurePushNotificationService for sending notifications via Azure Notification Hubs.
• Example usage in a controller:

  public class NotificationsController : ControllerBase
  {
      private readonly IAzurePushNotificationService _azurePushNotificationService;
  
      public NotificationsController(IAzurePushNotificationService azurePushNotificationService)
      {
          _azurePushNotificationService = azurePushNotificationService;
      }
  
      [HttpPost("send-azure-notification")]
      public async Task<IActionResult> SendAzureNotification(string message, string tag)
      {
          await _azurePushNotificationService.SendNotificationAsync(message, tag);
          return Ok("Notification sent via Azure!");
      }
  }

Firebase Push Notifications

• Store data in Firestore using the FirebaseRepository and send notifications via Firebase Admin SDK.
• Example usage:

  public class FirebaseController : ControllerBase
  {
      private readonly IUserRepository _userRepository;
  
      public FirebaseController(IUserRepository userRepository)
      {
          _userRepository = userRepository;
      }
  
      [HttpPost("send-firebase-notification")]
      public async Task<IActionResult> SendFirebaseNotification(string userId, string message)
      {
          var user = await _userRepository.GetUserAsync(userId);
          if (user == null) return NotFound("User not found!");
  
          // Logic to send notification using FirebaseAdmin SDK...
          return Ok("Notification sent via Firebase!");
      }
  }

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🔗 API Endpoints

Notification Endpoints

• POST /send-azure-notification: Send a push notification via Azure Notification Hub.
• POST /send-firebase-notification: Send a push notification via Firebase.

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🔑 Key Components

• IAzurePushNotificationService
  Handles communication with Azure Notification Hub.

• IFirebaseRepository<>
  Generic repository for Firestore operations.

• UserRepository
  Custom repository to manage users in Firestore.

• NotificationHubOptions
  Configuration for Azure Notification Hub.

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📜 License

This project is licensed under the MIT License.

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🙌 Contributing

Contributions are welcome! If you have ideas to improve the project, feel free to fork the repository, make changes, and submit a pull request.

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❤️ Acknowledgments

Special thanks to Firebase, Azure, and the .NET Community for their robust tools and resources that make development simpler and more effective.