Notification Center

1. Project Overview

Purpose

The Notification Center is a microservice designed to manage notifications for Giveth.io and other DApps. It provides a centralized system for handling various types of notifications across different platforms.

Key Features

• Centralized notification management
• Support for multiple DApps
• RESTful API interface
• Real-time notification delivery
• Customizable notification settings

Live Links

• Production: https://notification.giveth.io/
• Staging: https://notification.serve.giveth.io/

2. Architecture Overview

System Diagram

graph TD
    A[Client Applications] --> B[Notification Center API]
    B --> C[PostgreSQL Database]
    B --> D[Redis Cache]
    B --> E[External Services]
    E --> G[Ortto Email Services]

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Tech Stack

• Runtime: Node.js v16
• Language: TypeScript v4.5.2
• Database: PostgreSQL v14.2
• ORM: TypeORM v0.3.6
• Caching: Redis v5.0.9
• API Framework: Express v4.17.3
• Containerization: Docker Compose v3.3
• Documentation: Swagger/OpenAPI
• Testing: Mocha v9.2.2
• CI/CD: GitHub Actions

Data Flow

1. Client applications send notification requests to the API
2. Requests are validated and processed through middleware
3. Notifications are stored in PostgreSQL
4. Real-time notifications are cached in Redis
5. Notifications are delivered to appropriate users through Ortto API to send emails and manage tags

3. Getting Started

Prerequisites

• Node.js v16 (use nvm use to load appropriate version)
• Docker and Docker Compose
• PostgreSQL v14.2
• Redis v5.0.9

Installation Steps

1. Clone the repository:

   git clone git@github.com:Giveth/notification-center.git
   cd notification-center

2. Install dependencies:

   yarn i

3. Set up the development environment:

   docker-compose -f docker-compose-local-postgres-redis.yml up -d

4. Configure environment variables:

   • Copy config/example.env to config/development.env
   • Update the values in development.env as needed

5. Run database migrations:

   yarn run db:migrate:run:local

6. Start the development server:

   yarn start

7. Access the API documentation at http://localhost:3040/docs

4. Usage Instructions

Running the Application

• Development: yarn start
• Staging: yarn run start:server:staging
• Production: yarn run start:server:production

Testing

# Run all tests
yarn run test

# Run specific test files
yarn run test:notificationRepository
yarn run test:notificationSettingRepository

Database Management

• Create new migration:

  typeorm migration:create ./migrations/createNotificationTable

• Run migrations:

  yarn run db:migrate:run:local

• Revert last migration:

  yarn run db:migrate:revert:local

5. Deployment Process

Environments

• Development: Local development environment
• Staging: Pre-production testing environment
• Production: Live production environment

Deployment Steps

1. Build the application:

   yarn run build

2. Run database migrations:

   yarn run db:migrate:run:production

3. Start the server:

   yarn run start:server:production

CI/CD Integration

The project uses GitHub Actions for continuous integration and deployment. The workflow is defined in .github/workflows/{main-staging}-pipeline.yml.

6. Troubleshooting

Common Issues

1. Database Connection Issues

   • Verify PostgreSQL is running
   • Check environment variables
   • Ensure migrations are up to date

2. Redis Connection Issues

   • Verify Redis is running
   • Check Redis configuration
   • Ensure proper network connectivity

Logs and Debugging

• Install bunyan for better log visualization:

  yarn i -g bunyan

• View logs:

  tail -f logs/notification-center.log | bunyan

References

• Linting TypeScript using ESLint and Prettier
• REST API with Express TypeScript