Readiness names the daemon, not a Go template error - #237
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Building the deployment image found this: the image has the Docker CLI and no
daemon, and `check()` reported
template: :1:2: executing "" at <.ServerVersion>: reflect: indirection
through nil pointer to embedded struct field Info
Asked with `--format`, an unreachable daemon still makes the CLI render a
mostly-nil `Info` struct, so the template error is the LAST line of stderr and
"Cannot connect to the Docker daemon" is above it. `check()` took the last
line, so `/api/readiness` and `doctor` would have blamed reflection for a
stopped service — a message naming the wrong component, which is the failure
this repository keeps paying for.
`docker info` is now asked without a format, the exit code decides, and the
reported line is the one a person can act on: template noise is a consequence
of the daemon being absent, never the reason. A daemon that answers reports
its parsed `Server Version:`.
Found by deploying, not by reading. The dev host has the same CLI-without-
daemon shape and never surfaced it, because the failing assertion only fires
where `docker info` produces the template error rather than a plain refusal.
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Found while building the deployment image, which is a host with the Docker CLI installed and no daemon reachable.
DockerEnvironmentFactory.check()randocker info --format {{.ServerVersion}}and reported the last line of stderr. With a format string an unreachable daemon still renders a mostly-nilInfostruct, so the last line is a Go template error aboutindirection through nil pointer to embedded struct field Info, and the line that saysCannot connect to the Docker daemonsits above it.So
/api/readinessanddoctorwould have told an operator that reflection was stopping the fleet. That is a message naming the wrong component — the failure class this repository has paid for repeatedly.docker infois now asked with no format, the exit code decides readiness, and the reported line is the one a person can act on. A daemon that answers reports its parsedServer Version:.Two regression tests pin it, including that empty stderr still names the component instead of going blank.
Failing run: https://github.com/TheDancingDeveloper-org/agent-harness/actions/runs/31245089056