production-evyos-systems-and-services-3/ServicesBank/Email/README.md

Email Service

Overview

The Email Service is the first component in a Redis pub/sub processing chain for bank-related email automation. It monitors a specified mailbox for emails with attachments, filters them based on IBAN criteria, and publishes the data to a Redis channel for further processing.

Features

Email Processing

• Connects to a configured mailbox using IMAP
• Implements smart date-based filtering:
  • Checks emails from the past 14 days on the first run of each day
  • Checks emails from the past 7 days on subsequent runs within the same day
• Extracts attachments from emails
• Filters attachments based on IBAN criteria
• Uses a context manager to ensure emails are properly handled even during errors

Redis Integration

• Publishes messages to a Redis pub/sub channel ("CollectedData")
• Each message contains:
  • Unique UUID
  • Timestamp
  • Initial stage marker ("red")
  • Attachment payload and metadata
• Connects to an external Redis server

Error Handling

• Robust error management with context managers
• Automatic marking of emails as unread if processing fails
• Comprehensive logging

Configuration

Environment Variables

EMAIL_HOST=10.10.2.34
EMAIL_USERNAME=isbank@mehmetkaratay.com.tr
EMAIL_PASSWORD=system
EMAIL_SLEEP=60
AUTHORIZE_IBAN=4245-0093333
REDIS_HOST=10.10.2.15
REDIS_PORT=6379
REDIS_PASSWORD=your_strong_password_here

Deployment

Docker

The service is containerized using Docker and can be deployed using the provided Dockerfile and docker-compose configuration.

# Build and start the service
docker compose -f bank-services-docker-compose.yml up -d --build

# View logs
docker compose -f bank-services-docker-compose.yml logs -f email_service

# Stop the service
docker compose -f bank-services-docker-compose.yml down

Service Management

The check_bank_services.sh script provides a simple way to restart the service:

./check_bank_services.sh

Architecture

Redis Pub/Sub Chain

This service is the first in a multi-stage processing chain:

1. Email Service (this service): Reads emails, extracts attachments, publishes to Redis with stage="red"
2. Processor Service: Subscribes to stage="red" messages, processes data, republishes with stage="processed"
3. Writer Service: Subscribes to stage="processed" messages, writes data to final destination, marks as stage="completed"

Development

Dependencies

• Python 3.12
• Redbox (email library)
• Redis

State Management

The service maintains a state file at /tmp/email_service_last_run.json to track when it last ran, enabling the smart date-based filtering feature.