All-in-One FastAPI Backend for Telegram Mini-Apps

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This project provides a robust and efficient backend solution designed specifically for handling Telegram mini-apps. It leverages the power of FastAPI, providing high performance, easy-to-use endpoints, and seamless integration with various services like Redis, RabbitMQ, and PostgreSQL.

Features

• High Performance: Utilizes FastAPI for fast, asynchronous request handling.
• Database Integration: Supports PostgreSQL with both standard and Psycopg2 connectors.
• Messaging Support: Integrates with RabbitMQ for message brokering.
• Caching: Utilizes Redis for caching purposes.
• Scalable Architecture: Configurable connection pooling and overflow management.
• Easy Deployment: Environment variables for configuration to streamline deployment.
• Observability: Integrates with Prometheus, Loki, Grafana, and Tempo for monitoring, logging, and tracing.

Getting Started

Prerequisites

• Python 3.11
• PostgreSQL
• Redis
• RabbitMQ
• Docker & Docker Compose

Installation

1. Install the dependencies:

   poetry install

2. Set up the environment variables:

   Create a .env file in the root directory of the project and populate it with your configuration values. Use the .env.example file as a reference:

   DATABASE_URL=postgresql+asyncpg://postgres:password@localhost/mini_app_db
   DATABASE_URL_PSYCOPG2=postgresql+psycopg2://postgres:password@localhost/mini_app_db
   
   DB_USERNAME=postgres
   DB_PASSWORD=password
   DB_HOST=localhost
   DB_PORT=5432
   DB_DATABASE=mini_app_db
   
   TRACEBACK_OUTPUT_ENABLED=True
   
   REDIS_HOST=localhost
   REDIS_PORT=6379
   
   RABBITMQ_HOST=localhost
   RABBITMQ_PORT=5672
   RABBITMQ_USER=guest
   RABBITMQ_PASSWORD=guest
   
   ASYNC_ENGINE_POOL_SIZE=20
   ASYNC_ENGINE_MAX_OVERFLOW=50
   
   BOT_LINK=<BOT_LINK>
   
   BOT_TOKEN=<BOT_TOKEN>
   
   OTLP_GRPC_ENDPOINT=http://localhost:4317

3. Create postgres database, e.g. mini_app_db.

4. alembic upgrade head to apply migrations.

Integrate with your Telegram Mini-App:

Your Telegram Mini-App should send initialization data using POST, PUT requests in the following format:

{
  "initData": "query_id=<query_id>&user=%7B%22id%22%3A456158277%2C%22first_name%22%3A%22John%20Doe%22%2C%22last_name%22%3A%22%22%2C%22username%22%3A%22john_doe%22%2C%22language_code%22%3A%22en%22%2C%22is_premium%22%3Atrue%2C%22allows_write_to_pm%22%3Atrue%7D&chat_instance=<CHAT_INSTANCE>&chat_type=private&auth_date=<AUTH_DATE>&hash=<HASH>"
}

Docker Compose Setup

The project includes a docker-compose.yml file that sets up the entire stack for you, including the database, caching, messaging, and monitoring services.

Running the Application with Docker Compose

To start the entire application stack using

Docker Compose, follow these steps:

1. Build and start the containers:

   docker-compose up --build -d

2. Access the services:

   • API: http://localhost:8000
   • Grafana: http://localhost:3000
   • Prometheus: http://localhost:9090
   • Loki: http://localhost:3100
   • Tempo: http://localhost:4317
   • RabbitMQ Management: http://localhost:15672