raisultan / tg-bot-service

Telegram Bot Microservice implemented with FastAPI and Telethon

Telegram Bot Microservice

Basis for extendable, high-performance Telegram Bot microservice.

Tech Stack

• FastAPI
• Telethon
• AsyncIO
• Docker & docker-compose

Features

Receiver Service

• Updates Receiver [Telethon / MTProto] - receive updates on any action made by user directed to Telegram Bot/Account. Similar to Webhook Server or Long Polling, but faster and more stable due to use of MTProto protocol which is Telegram Native. More on this topic.
• Basic event handler - currently to stay as generic as possible service implements basic conversation. Functionality can be extended by adding new handlers.
• Async API Driver [HTTPX] - HTTP/REST API Driver to interact with other services.
• Logger for API Driver [Native Python Logger] - to monitor and log each request and response. Additionally, keeps logs in files to use with monitoring tools, such as ELK, Prometheus+Grafana, etc.

Sender Service

• Async API [FastAPI] - receive requests from other services. Endpoints:
  • /api_v1/send_message - send plain message to user
  • /api_v1/send_multiple_message - send multiple messages to multiple users
  • /api_v1/create_document - create document on Telegram Servers and receive its ID, to later reuse
  • /api_v1/send_document - send document by Telegram ID
  • /api_v1/send_multiple_documents - send multiple documents to multiple users
• Sender [Telethon] - Telegram Client that will be triggered to execute some business logic after successful processing of request received by API, in other words to send updates to user.

Whole Service Workflow

As it can be understood, this microservice is not "killer-beast" and is not suitable for all use-cases. It is mostly oriented for offload, high-speed interaction with users through Telegram.

Ideal workflow of service is following:

• user sends update to Telegram Bot/Account, which is received by specific event handler of Receiver
• event handler processes received data, adjusts it if needed and sends this data to Other Microservice through API Driver, note that you can implement as many API Drivers as you need to interact with your services.
• Other Microservice processes and executes its own business logic and sends result of processing to API.
• API receives the data from other service and transfers it Telegram through Sender, which is Telegram Client provided by Telethon.

Thus, we have fully autonomous, loosely-coupled microservice.

Workflow Scheme

How to Use

Root directory has docker-compose file through which whole microservice can be started. But firstly, build images:

docker-compose build

And start up services:

docker-compose up

Sender service API can be found on http://0.0.0.0:8001 and docs on http://0.0.0.0:8001/docs

Enhancement, contribution, and feedback

Any feedback or contribution to the project is eagerly welcomed. Just create an issue or contact me on [email protected].

Recommended for reading:

• https://docs.telethon.dev/en/latest/quick-references/faq.html

Todo:

• logging for FastAPI
• logging for Telethon event handlers