The CI runs go test with -race; the agent runner has two pump goroutines
(pumpStdout + pumpStderr) writing through the sender concurrently, and
the unprotected fakeSender slice append raced. The cancel_test had a
local 'safeSender' workaround for the same issue; promote that mutex
onto fakeSender itself so every test in the package is race-clean
without per-test variants.
- fakeSender grows mu sync.Mutex; Send takes/releases. New snapshot()
helper for tests that want a stable copy.
- cancel_test drops its local safeSender + sync import; uses fakeSender.
Verified: go test -race ./... passes across all packages.
Wires the existing job_detail Cancel button (which was a UI stub) into
real backend behaviour:
- internal/api already declared MsgCommandCancel + CommandCancelPayload;
promote those from forward-declarations to a working envelope. Agent
side: cmd/agent/main.go drops the TODO-stub and gains a per-job
ctx.CancelFunc map. runJob's switch is refactored around a small
spawn() helper so each kind's goroutine derives a per-job context,
registers the cancel, and removes itself on completion regardless of
outcome. command.cancel looks up the func and fires it.
- internal/agent/runner.sendFinished now takes ctx and rebadges
ctx.Canceled errors as JobCancelled (exit 130) rather than
JobFailed. All Run* call sites updated.
- internal/restic.resticCmd sets cmd.Cancel to send SIGTERM (via
build-tagged sigterm constant; os.Kill on Windows since SIGTERM
isn't deliverable there) and cmd.WaitDelay=5s for the SIGKILL
fallback. SIGTERM lets restic remove its lock file before exiting.
- New POST /api/jobs/{id}/cancel server endpoint validates the job
is non-terminal and the host is online, sends command.cancel via
the hub, writes a job.cancel audit row, returns 202. The agent's
resulting job.finished (status=cancelled) is what actually
transitions the row.
Tests:
- internal/server/http/cancel_test.go covers happy path (envelope
shape + audit row), 409 for terminal jobs, 404 for missing jobs,
503 for offline hosts.
- internal/agent/runner/cancel_test.go covers cancel mid-run: a fake
restic that exec'd into 'sleep 30' is canceled 150ms after start
and the resulting job.finished reports JobCancelled with exit 130
in well under the WaitDelay.
Foundational for P3 restore (operator needs to be able to cancel a
running backup if they need to restore urgently). Independently useful
for prune/check/backup that are stuck.
steve