erfiume_bot

Introduction

@erfiume_bot it's a Telegram bot that fetches the water levels of the rivers in Emilia Romagna. Data is retrieved from Allerta Meteo Emilia Romagna APIs and periodically stored/updated in a DynamoDB table. The bot can be used in both private or group chats, responding to specific station names or commands.

Basic commands:

• /start
• /info
• /stazioni
• /<stazione_name> where <stazione_name> is one the station reported on Livello Idrometrico

Architecture

The bot consists of two main components:

1. User interaction: the code in ./app/bot is triggered by a Telegram webhook that starts an AWS Lambda function when a user interacts with the bot.
2. Stations data update: the code in ./app/fetcher runs on a Lambda function via an EventBridge scheduler, updating the data from the stations. This data is then used by the bot to answer to messages.

Main technologies:

• Pulumi for IaC
• AWS Lambda for main code execution environment
• DynamoDB for storing station data
• EventBridge Scheduler to trigger the syncing from Allerta Meteo
• teloxide to manage Telegram inputs
• tokio for managing asynchronous tasks in the Lambdas
• Levenshtein Distance for performing fuzzy search on station names from user input

Features

Telegram Bot (./app/bot)

The bot responds to Telegram messages via the main Lambda function and can:

• respond to any message or command (/) in private chats
• react when added to a group or supergroup
• process any command (/) in group or supergroup chats

What it cannot do:

• read non-command messages in groups or supergroups
• provide inline support
• support mentions

Data fetcher (./app/fetcher)

This Lambda function is scheduled to fetch data from the APIs on Allerta Meteo Emilia Romagna and update or create station data in a DynamoDB table. A station refers to a sensor placed on a bridge or river that monitors the water level.

The Lambda is scheduled to run once a day in "normal" mode, but in "emergency" mode, it can be set to update data every 20 minutes or less.

Repository Structure

• app/: Contains the bot and fetcher code
• pulumi/: IaC for the AWS infrastructure

Disclaimer

The accuracy and reliability of the data is entirely dependent on Allerta Meteo Emilia Romagna. erfiume_bot merely collects and displays the available data from that source.