# Postfix probe

A real Postfix delivers MAS addresses through the `pipe` transport to
`mas-gateway` and on to the reference ticket service. A capture proxy
(`capture.py`) records the envelope recipient each event carried, so the
probe can tell whether Postfix rewrote anything.

```bash
docker build -t mas-postfix-probe experiments/postfix-probe
python3 experiments/postfix-probe/probe.py --profile defaults            # relay domain
python3 experiments/postfix-probe/probe.py --profile local-domain        # domain in mydestination
python3 experiments/postfix-probe/probe.py --profile local-domain-safe   # + swap_bangpath/percent_hack off
```

The other profiles are `defaults-local` and `mas-safe-local`. The repo is
mounted read-only. In `results/` a `=` mark means the address arrived
unchanged and `!` means it was rewritten. Findings are in
`docs/experiment-review.md` under *Email infrastructure*.

The Postfix side is the `master.cf` entry in `entrypoint.sh`:

```
mas  unix  -  n  n  -  -  pipe
  flags=Rq user=mas argv=/usr/local/bin/mas-gateway --statute <statute>
  pipe --app-url http://127.0.0.1:8024/mas-events --recipient ${recipient}
```

Set `mas_destination_recipient_limit = 1` so each pipe invocation handles
one recipient.