# 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 mas-profile --corpus  # the shipped profile
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
```

`mas-profile` runs the shipped integration profile
(`integrations/postfix/`) with `--corpus` (every conformance-corpus
local-part), plus relay attempts that must be refused. `pytest` runs it as
`tests/test_postfix_profile.py` when Docker is available. The other
experiment profiles are `defaults-local` and `mas-safe-local`. The repo is
mounted read-only. In the output, `=` means the address arrived unchanged,
`~` means only its RFC 5321 quoting changed, `!` means it was rewritten, and
`R` means a relay attempt was refused. 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.