Moodle renders the same msmtprc as WordPress and mounts it into two services,
but nothing ever proved a message left the container: its healthcheck opens the
FPM port and nothing else. Moodle 0 of run 31658241728 passed green while mail
could not have worked -- the defect 2da285067 fixed for WordPress was invisible
here, and would have stayed invisible until a user reset a password.
WordPress proves delivery with the msmtp_curl flavor: the probe sends one mail
and writes a marker, and a task after convergence waits for that marker. Moodle
cannot use it, because curl cannot judge a port that answers FastCGI. Rather
than add a second msmtp_* class per liveness shape, the declaration now composes:
healthcheck:
flavor:
- msmtp
- connect
port_key: fpm
msmtp stops being a flavor and becomes a prefix -- shell that runs on the way
past and never decides liveness. connect joins the probes as the one that only
asks whether the port accepts a TCP connection. A declaration names exactly one
probe and any number of prefixes, as a string or a list; msmtp_curl stays as an
alias for [msmtp, curl], and the lint that validates declarations now shares
resolve_flavors with the lookup instead of keeping its own idea of a flavor.
The module became five responsibilities in one file, so it is a package:
probes.py answers which probes exist, prefixes.py what runs before them,
compose.py how a declaration becomes a rendered block. The curl helpers sit with
the probes and mail_branch with the prefix -- each next to its only caller,
rather than together in a module header.
Two defects in this work were found by measuring, not reading:
- the timing merge took the maximum across prefixes only, which cut Moodle's
start period from 15m to 120s and would have marked a heavy PHP app dead
while it was still installing. A prefix may now raise a timing and never
lower one, pinned by test.
- composing moved msmtp_curl's interval from 30s to 1m, because the composed
class derives from Curl where MsmtpCurl derived from Probe. That is the
interval every other curl probe uses, but it was not intended; it now has
its own test rather than riding along unseen.
Regression measured across the whole repo rather than argued: every declared
healthcheck was rendered with the pre-refactor code and with this one. 58 render
byte-identically, 1 is Moodle's intentionally changed declaration, and 2 differ
-- friendica and wordpress, in that interval alone, with the probe command
itself unchanged.
Coverage was checked in both directions. No test was removed: the four deleted
lines are an import, the registry literal, one class name in a url test, and the
helper, which now goes through compose() instead of reaching into PROBES -- a
tightening. New code had two gaps, both closed: connect was the only probe whose
emitted command no test pinned, and compose() raised KeyError for an unknown
name unobserved.
Not verified: no deploy has run any of these probes. The composed class is built
dynamically, so what it emits is proven for all 59 services while docker
accepting it is not.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The msmtp_curl probe joined its mail branch to the curl probe with '&&', so a
relay that refuses the startup message short-circuited the whole command: curl
never ran, the container stayed unhealthy forever, and the swarm converge gate
burned all 150 retries before aborting the deploy. Friendica 0 and Fediwall 0
of run 31340965955 died that way, reporting only 'not converged:
friendica_friendica' with the real cause buried in a rescue artifact.
That contradicted the probe's own docstring, which promises an unrelated SMTP
outage cannot flap the container into unhealthy -- it only delivered that for
email_enabled=False. sys-ctl-hlth-msmtp/files/script.sh:23 has always tolerated
exactly these exit codes; the container probe was the outlier.
Liveness is now curl's verdict alone. The '&&' before touch stays, so a refused
mail leaves no marker and the next probe retries it rather than turning the
smoke test one-shot.
Detection does not disappear with the coupling: web-app-friendica now asserts
the delivery marker after convergence and fails with the relay's reason instead
of a timeout three layers away. sys-ctl-hlth-msmtp is a systemd timer and the
Mailu Playwright roundtrip submits through Roundcube, so neither covers a
container relaying over port 25 -- this assertion is what does.
The marker path moves into utils.docker.healthcheck.MAIL_MARKER and reaches
Ansible through lookup('container_mail_marker'), so the probe and the assertion
cannot drift apart.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
kevinveenbirkenbachandClaude Opus 5