Required environment variables:
- EWS_USERNAME - username for authentication with Exchange Web Services
- EWS_PASSWORD - password for authentication with EWS
- DB_HOST - database hostname (server URL)
- DB_NAME - database name
- DB_USER - database username with global read and write rights
- DB_PASSWORD - password for the database user
- SMTP_URL - URL to the SMTP server used for distributing log files
- SMTP_USER - username for SMTP login
- SMTP_PASSWORD - password for SMTP login