routine crontab service tested and completed added to Readme.md

BankServices/RoutineEmailService/README.md

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+# Routine Email Service
+
+## Overview
+This service sends automated email reports about account records at scheduled times using cron. It retrieves account records from a PostgreSQL database, formats them into an HTML email, and sends them to specified recipients.
+
+## Environment Setup
+The service requires the following environment variables:
+
+### Email Configuration
+- `EMAIL_HOST`: SMTP server address (e.g., "10.10.2.34")
+- `EMAIL_USERNAME`: Email sender address (e.g., "example@domain.com")
+- `EMAIL_PASSWORD`: Email password (sensitive)
+- `EMAIL_PORT`: SMTP port (e.g., 587)
+- `EMAIL_SEND`: Flag to enable/disable email sending (1 = enabled)
+
+### Database Configuration
+- `DB_HOST`: PostgreSQL server address (e.g., "10.10.2.14")
+- `DB_USER`: Database username (e.g., "postgres")
+- `DB_PASSWORD`: Database password (sensitive)
+- `DB_PORT`: Database port (e.g., 5432)
+- `DB_NAME`: Database name (e.g., "postgres")
+
+## Cron Job Configuration
+The service is configured to run daily at 11:00 Istanbul Time (08:00 UTC). This is set up in the entrypoint.sh script.
+
+## Docker Container Setup
+
+### Key Files
+
+1. **Dockerfile**: Defines the container image with Python and cron
+
+2. **entrypoint.sh**: Container entrypoint script that:
+   - Creates an environment file (/env.sh) with all configuration variables
+   - Sets up the crontab to run run_app.sh at the scheduled time
+   - Starts the cron service
+   - Tails the log file for monitoring
+
+3. **run_app.sh**: Script executed by cron that:
+   - Sources the environment file to get all configuration
+   - Exports variables to make them available to the Python script
+   - Runs the Python application
+   - Logs environment and execution results
+
+### Environment Variable Handling
+Cron jobs run with a minimal environment that doesn't automatically include Docker container environment variables. Our solution:
+
+1. Captures all environment variables from Docker to a file at container startup
+2. Has the run_app.sh script source this file before execution
+3. Explicitly exports all variables to ensure they're available to the Python script
+
+## Logs
+Logs are written to `/var/log/cron.log` and can be viewed with:
+```bash
+docker exec routine_email_service tail -f /var/log/cron.log
+```
+
+## Manual Execution
+To run the service manually:
+```bash
+docker exec routine_email_service /run_app.sh
+```
+
+## Docker Compose Configuration
+In the docker-compose.yml file, the service needs an explicit entrypoint configuration:
+```yaml
+entrypoint: ["/entrypoint.sh"]
+```
+
+This ensures the entrypoint script runs when the container starts.