matrix_synapse_systemd_service_post_start_delay_seconds is assigned a string value, and setup fails while creating the service file. It is impossible to compare str and int.
Switch the systemd ExecStartPost health check from docker exec + curl
to polling docker inspect for container health status. This piggybacks
on the container image's built-in HEALTHCHECK instead of duplicating it.
Also add a configurable container health interval (5s for Traefik setups,
15s otherwise) to speed up startup readiness detection without affecting
non-Traefik deployments.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Previously, we had a 10-second magical delay.
Now we first do a healthcheck to figure out when it really is up.
Then, we do the same 10-second magical delay to account for the time it
may take for a reverse-proxy (like Traefik) to pick up Synapse's routes.
This is an attempt at optimizing service startup.
The effect is most pronounced when many services are restarted one by one.
The systemd service manager role sometimes does this - for example when `just install-service synapse` runs.
In such cases, a 5-second delay for each Synapse worker service
(or other bridge/bot service that waits on the homeserver) quickly adds up to a lot.
When services are all stopped fully and then started, the effect is not so pronounced, because
`matrix-synapse.service` starts first and pulls all worker services (defined as `Wants=` for it).
Later on, when the systemd service manager role "starts" these worker services, they're started already.
Even if they had a 5-second wait each, it would have happened in parallel.
