PR #30136 review caught a false positive: when HERMES_DASHBOARD was
unset, the dashboard run script did `exec sleep infinity`, so
`s6-svstat /run/service/dashboard` reported the slot as 'up'.
`hermes doctor` and any other s6-svstat-based health check saw the
dashboard as supervised-running even though no dashboard process
existed.
Add cont-init.d/03-dashboard-toggle: writes a `down` marker file
into `/run/service/dashboard/` when HERMES_DASHBOARD is falsy,
removes any leftover marker when it's truthy. s6-supervise honors
`down` by not starting the service, so s6-svstat reports 'down' —
matching reality.
The run script's HERMES_DASHBOARD case-statement stays in place as
a belt-and-suspenders guard, so the two layers can never disagree.
Two new integration tests lock the behavior: slot reports down
when unset; slot reports up when set to 1.
PR #30136 review surfaced two issues, both rooted in the same audit gap:
docker integration tests were running as root, not the unprivileged
`hermes` user (UID 10000) that the runtime actually uses via
`s6-setuidgid hermes`. Anything that probed PID-1 state or wrote to
the s6 control surface worked as root in the tests but was inert in
production.
Fixes:
1. `_s6_running()` previously called `Path("/proc/1/exe").resolve()`,
which is root-only readable. For UID 10000 the symlink yields
PermissionError, `resolve()` silently returns the unresolved path,
and `exe.name == "exe"` — so detection always returned False, the
service-manager runtime-registration path was inert, and every
`hermes profile create` / `hermes -p X gateway start` silently
skipped the s6 hook. Replace with `/proc/1/comm` (world-readable)
+ `/run/s6/basedir` (s6-overlay-specific) — both required, fail
closed.
2. `02-reconcile-profiles` now also chowns `/run/service/.s6-svscan/`
{control,lock} to hermes so `s6-svscanctl -a/-an` works without
root. Previously the directory chown stopped at `/run/service`
and the FIFO inside stayed root-owned, so `register_profile_gateway`
from hermes failed at the rescan-trigger step with EACCES — the
wrapper in profiles.py caught the exception and printed a swallowed
warning, so profile creation appeared to succeed while the slot
was rolled back.
Audit changes to flush this class of bug next time:
- Add `docker_exec` / `docker_exec_sh` helpers to `tests/docker/conftest.py`
that default to `-u hermes`. The module docstring explains why and
flags `user="root"` as opt-in only for tests that explicitly need
root (none currently do).
- Refactor every `docker exec` call in tests/docker/ through the new
helpers (test_dashboard.py, test_zombie_reaping.py, test_profile_gateway.py,
test_container_restart.py, test_s6_profile_gateway_integration.py).
- Add 5 unit tests covering `_s6_running` under various probe states
(both signals present; comm wrong; basedir missing; PermissionError
on /proc/1/comm; missing /proc — non-Linux). The PermissionError
test is the explicit regression guard for the original bug.
Known follow-up: the per-service `supervise/control` FIFO inside each
`/run/service/gateway-<profile>/supervise/` is created root-owned by
s6-supervise (which runs as root because s6-svscan is PID 1). `s6-svc
-u/-d/-t` from the hermes user will get EACCES on those. The audit
under `-u hermes` will reveal this in lifecycle tests — surfacing the
issue cleanly so it can be fixed in a focused follow-up (likely via a
small SUID helper or a polling chown loop in cont-init.d). The
detection + svscanctl fixes here are independent and complete on
their own.
BREAKING CHANGE: the container ENTRYPOINT is now /init (s6-overlay)
instead of /usr/bin/tini. Main hermes runs as the container CMD with
TTY inherited (preserving --tui), dashboard runs as a supervised s6-rc
service (HERMES_DASHBOARD=1 starts it; crashes auto-restart), and the
ground is laid for per-profile gateway supervision (Phase 3+4).
All five pre-s6 docker run invocation patterns continue to work
identically — verified by the Phase 0 docker harness:
docker run <image> → `hermes` with no args
docker run <image> chat -q "..." → `hermes chat -q ...` passthrough
docker run <image> sleep infinity → `sleep infinity` direct
docker run <image> bash → interactive bash
docker run -it <image> --tui → interactive Ink TUI
Phase 2 harness result: 12 passed, 2 xfailed (Phase 4 target). Hadolint
+ shellcheck pass cleanly.
Architecture pivot from plan v3 (documented in main-hermes/run header):
the plan called for main hermes to be an s6-supervised service, but
two real s6-overlay v3 mechanics blocked that — cont-init.d scripts
receive no arguments (CMD args are not visible to stage2-hook), and
`/run/s6/basedir/bin/halt` after writing the exit code did not
propagate the desired exit code (container exits 143). We use the
s6-overlay-native CMD pattern instead: main-wrapper.sh is the
container's main program (ENTRYPOINT prepends it so leading-dash
args like --version aren't intercepted by /init), exec's the final
program with stdin/stdout/stderr inherited, and the program's exit
code becomes the container exit code. main-hermes is now a no-op
`sleep infinity` slot kept for future supervised-gateway-container
modes. This trades "supervised restart of main hermes" for arg-
parity with the pre-s6 contract — main hermes was already unsupervised
under tini, so we lose nothing functional. Dashboard supervision is
the only new guarantee added by this phase.
Files added:
docker/main-wrapper.sh # arg routing + s6-setuidgid drop
docker/stage2-hook.sh # gosu-equivalent + chown + seed
docker/s6-rc.d/main-hermes/{type,run,dependencies.d/base}
docker/s6-rc.d/dashboard/{type,run,dependencies.d/base}
docker/s6-rc.d/user/contents.d/{main-hermes,dashboard}
Files changed:
Dockerfile: tini → s6-overlay install + ENTRYPOINT flip + service wiring
docker/entrypoint.sh: thin shim to stage2-hook.sh for back-compat
tests/docker/test_dashboard.py: add test_dashboard_restarts_after_crash
Refs: docs/plans/2026-05-07-s6-overlay-dynamic-subagent-gateways.md
Two pre-existing baseline issues found while running the Phase 0 harness
against the tini image that need fixing before later phases can use the
harness as a behavior-parity oracle:
1. The autouse `_enforce_test_timeout` fixture in tests/conftest.py
hard-coded a 30s SIGALRM, which preempted any `pytest.mark.timeout`
marker (already honored by pytest-timeout). Honor the marker if
present; fall back to 30s otherwise. Docker harness tests carry a
180s marker applied at collection time in tests/docker/conftest.py.
2. test_dashboard_port_override polled via `ss -tlnp` / `netstat -tln`
— neither is installed in the Hermes image, so the probe trivially
failed even when the dashboard was bound. The dashboard also takes
8-15s to bind on cold image; the 5s sleep was insufficient. Replace
with a poll loop reading /proc/net/tcp directly (port 9120 = 0x23A0,
state 0A = LISTEN). Bump probe deadline to 60s and switch
test_dashboard_opt_in_starts to a similar poll for pgrep so we don't
regress to the same race.
Result: 11 passed, 2 xfailed (Phase 4 target) on tini image. Harness
now ready to serve as Phase 2's behavior-parity oracle.
Tasks 0.2-0.6 of the s6-overlay supervision plan. Locks the
user-visible behavior we must preserve through the Phase 2 init-
system swap:
- test_main_invocation.py (Task 0.2): docker run <image> with no
args, chat subcommand passthrough, bare executable passthrough,
bash pattern, exit-code propagation
- test_tui_passthrough.py (Task 0.3): TTY allocation via docker -t
using the host's script(1) for a PTY
- test_dashboard.py (Task 0.4): HERMES_DASHBOARD=1 opt-in,
HERMES_DASHBOARD_PORT override
- test_profile_gateway.py (Task 0.5): per-profile gateway
start/stop and profile-delete-stops-gateway. Both marked
xfail(strict=True) because the current tini image refuses
gateway lifecycle commands inside the container; Phase 4
Task 4.3 flips them to passing.
- test_zombie_reaping.py (Task 0.6): PID 1 reaps orphaned
zombies. tini does this today; s6-overlay's /init must
continue to.
Refs: docs/plans/2026-05-07-s6-overlay-dynamic-subagent-gateways.md
