Retry docker compose up so a registry timeout does not redden main

[jeremydmiller]

Three of the four red main runs on 2026-08-03 were not test failures. CIOtel (twice, runs 30835955313 and 30782661294) and CIMQTT5 (30843486384) each died in under a minute, before a single test ran:

rabbitmq Error Get "https://registry-1.docker.io/v2/": context deadline exceeded

docker compose up contacts the registry for any image that is not already cached, and GitHub's runners time out against Docker Hub often enough to do this on their own. LaunchDockerServices fired exactly one attempt and asserted a zero exit code, so a single blip failed the whole job.

The change

ComposeUp makes three attempts with a 5s/10s backoff, logging the tool's own output on each failure, and throws the real message when they are exhausted.

Every failure is retried, not just registry-shaped ones. Matching on message text would be guessing at a moving target. A genuinely broken compose file still fails — it just takes three tries to get there, and the exception carries the real reason either way. Each failed attempt logs the output, so the job log states which case it was rather than leaving the reader to infer it.

DockerUp in build.cs was a byte-for-byte duplicate of the same single-shot logic and pulls every image in the compose file, making it the most exposed caller of all, so it now shares the helper.

Verification

Run against a nonexistent service via a temporary target — two warnings, then the genuine error, and a total elapsed time of 0:15 confirming the 5s + 10s backoff actually happened:

[WRN] docker compose up failed for no-such-service (attempt 1 of 3), retrying in 5s:
      no such service: no-such-service
[WRN] docker compose up failed for no-such-service (attempt 2 of 3), retrying in 10s:
      no such service: no-such-service
[ERR] docker compose up failed for no-such-service after 3 attempts:
      no such service: no-such-service
ProcessException: Process 'docker' exited with code 1.
   Error output:
      no such service: no-such-service

ProbeRetry         Failed          0:15

The success path is unchanged apart from a log line when it took more than one attempt.

🤖 Generated with Claude Code

https://claude.ai/code/session_01WHAuhdWS3XeAk16swV9G8m