chore: add documented POP3/SMTP proxy scaffold and Renovate config

2026-06-17 16:08:06 +01:00
parent a41fbf04da
commit e6eca290ba
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+# Legacy Email Proxy
+
+Proxy an unauthenticated, unencrypted POP3 / SMTP server to authenticated IMAPS and SMTPS backends.
+
+## Features
+
+- Exposes legacy `POP3` on `0.0.0.0:110` and legacy `SMTP` on `0.0.0.0:25`
+- Forwards POP3 mailbox access to an IMAP backend
+- Forwards SMTP submissions to an SMTPS backend
+- Backend host, ports, and credentials are configured via environment variables
+
+## Environment Variables
+
+- `POP3_BIND_ADDR` (default `0.0.0.0`)
+- `POP3_BIND_PORT` (default `110`)
+- `SMTP_BIND_ADDR` (default `0.0.0.0`)
+- `SMTP_BIND_PORT` (default `25`)
+
+- `BACKEND_IMAP_HOST`
+- `BACKEND_IMAP_PORT` (default `993`)
+- `BACKEND_IMAP_USER`
+- `BACKEND_IMAP_PASS`
+- `BACKEND_IMAP_USE_SSL` (default `true`)
+- `BACKEND_IMAP_USE_STARTTLS` (default `false`)
+
+- `BACKEND_SMTP_HOST`
+- `BACKEND_SMTP_PORT` (default `465`)
+- `BACKEND_SMTP_USER`
+- `BACKEND_SMTP_PASS`
+- `BACKEND_SMTP_USE_SSL` (default `true`)
+- `BACKEND_SMTP_USE_TLS` (default `false`)
+
+## Build and run
+
+This project targets the latest Python LTS release. The included `Dockerfile` uses `python:3.12-slim`, which is compatible with Python 3.12 and later LTS releases.
+
+```bash
+docker build -t legacy-email-proxy .
+docker run --rm -p 110:110 -p 25:25 \
+  -e BACKEND_IMAP_HOST=imap.example.com \
+  -e BACKEND_IMAP_PORT=993 \
+  -e BACKEND_IMAP_USER=imap-user \
+  -e BACKEND_IMAP_PASS=imap-pass \
+  -e BACKEND_SMTP_HOST=smtp.example.com \
+  -e BACKEND_SMTP_PORT=465 \
+  -e BACKEND_SMTP_USER=smtp-user \
+  -e BACKEND_SMTP_PASS=smtp-pass \
+  legacy-email-proxy
+```
+
+## Notes
+
+This implementation begins the proxy with a minimal POP3 command set and SMTP delivery path. It is designed to start development on the required application architecture.