Pre-s6, `docker run nousresearch/hermes-agent gateway run` was the
standard invocation: gateway ran as the container's main process,
tini reaped zombies, container exit code matched gateway exit code,
no supervision. With s6-overlay as PID 1, the same invocation now
auto-upgrades to supervised semantics — auto-restart on crash,
dashboard supervised alongside (when HERMES_DASHBOARD=1 is set),
multiple profile gateways under the same /init.
Users get the new behavior with zero changes to their docker run
command. A loud one-line breadcrumb on stderr explains the upgrade
and points at the opt-out for users who genuinely want pre-s6
foreground semantics.
How it works:
1. `_gateway_command_inner` (the `gateway run` handler) checks if
we're inside a container with s6 as PID 1.
2. If yes, dispatches `start` to the s6 service manager (registers
and starts gateway-default), then `exec sleep infinity` to keep
the CMD process alive without binding container lifetime to
gateway PID lifetime. The supervised gateway can flap freely;
`docker stop` still tears everything down via /init stage 3.
3. If no, falls through to the existing foreground code path
unchanged. Host runs of `hermes gateway run` are unaffected.
Three gates make the redirect inert outside the intended scope:
* `detect_service_manager() != "s6"` — host/non-s6-container runs.
* `HERMES_S6_SUPERVISED_CHILD=1` env var (recursion guard) —
exported by `S6ServiceManager._render_run_script` for the
s6-supervised invocation itself. Without this guard, the
supervised `gateway run --replace` would re-enter the redirect
and recurse (run → start → run → start → ...) infinitely.
* `--no-supervise` CLI flag OR `HERMES_GATEWAY_NO_SUPERVISE=1` env
var — explicit user opt-out for CI smoke tests, debugging the
foreground startup path, or any case wanting "CMD exit =
container exit" semantics. Strict truthiness (1/true/yes,
case-insensitive); typos like `=0` do NOT silently opt out.
Tests:
* Unit tests in tests/hermes_cli/test_gateway_s6_dispatch.py
cover all five paths (host no-op, supervised fire, sentinel
recursion guard, CLI flag, env var truthy + falsy). The two
load-bearing gates (sentinel + opt-out) were mutation-tested
by removing each gate in isolation and confirming the dedicated
test fails with the expected error.
* Docker harness tests in tests/docker/test_gateway_run_supervised.py
cover the round trips end-to-end against a built image: redirect
fires (sleep-infinity heartbeat + supervised gateway-default
slot + breadcrumb), --no-supervise opt-out (foreground gateway,
no want-up on the slot), HERMES_GATEWAY_NO_SUPERVISE env var
works identically, recursion is impossible (≤1 supervised
python gateway-run + exactly 1 sleep-infinity parented to the
CMD wrapper), and HERMES_DASHBOARD=1 produces both supervised
gateway and supervised dashboard.
Docs:
* Added a `:::tip Gateway runs supervised` admonition near the
main docker.md example explaining the upgrade and pointing at
the opt-out. Pre-s6 (tini-based) images still run gateway run
as the foreground main process, so the note is scoped to the
s6 image only.
Trade-off documented in the helper docstring: container exit code
under the redirect is sleep's exit code (always 0 on SIGTERM), not
the gateway's. That was an explicit design call — the supervised
gateway is allowed to flap without taking the container with it,
which is what "supervision" means. CI users who want exit-code
forwarding can pass --no-supervise.