fix(docker): stop containers and execs on step timeout - #2566
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timeout_sec only cancels ctx. Client.Run then polled with context.Background() and never ContainerStop, so a long sleep hung until the process exited. Shared-container Exec left the process running because TerminateOnCancel defaulted false. Stop the container once on cancel, and pass TerminateOnCancel plus a pid file on native execs so only the step process is killed.
📝 WalkthroughWalkthroughDocker runtime execution now uses cancellation-aware native options. Container shutdown polling responds to context cancellation, stops running containers with ChangesDocker cancellation flow
Estimated code review effort: 3 (Moderate) | ~30 minutes Merge Risk: 🟡 Moderate · up to A timed-out container can still hang indefinitely when the stop request fails, preventing the step from completing and potentially leaving resources running. This localized cancellation failure should be fixed or explicitly accepted before merging. Sequence Diagram(s)sequenceDiagram
participant ClientRun
participant DockerDaemon
participant DockerContainer
participant Context
ClientRun->>DockerDaemon: execute command with nativeExecOptions
Context-->>ClientRun: cancellation
ClientRun->>DockerDaemon: inspect container state
ClientRun->>DockerDaemon: stop running container with SIGKILL
DockerDaemon-->>ClientRun: stopped or not-found result
ClientRun-->>Context: return command or wait error
🚥 Pre-merge checks | ✅ 5✅ Passed checks (5 passed)
✨ Finishing Touches🧪 Generate unit tests (beta)
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Actionable comments posted: 1
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Inline comments:
In `@internal/runtime/builtin/docker/cancel.go`:
- Around line 29-33: Update the requestStop closure in the cancellation flow to
preserve and propagate the error returned by stop instead of discarding it,
ensuring a failed container stop terminates the surrounding wait rather than
relying on stopOnce for another attempt. Add coverage for a failing stop with
inspect continuing to report running=true, verifying the operation returns
instead of hanging.
🪄 Autofix
Fix all unresolved CodeRabbit comments on this PR:
- Push a commit to this branch (recommended)
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📒 Files selected for processing (4)
internal/runtime/builtin/docker/cancel.gointernal/runtime/builtin/docker/cancel_test.gointernal/runtime/builtin/docker/client.gointernal/runtime/builtin/docker/executor.go
Code review on dagucloud#2566: a no-op Client.Stop left waitUntilContainerStopped polling forever, and the pid wrapper backgrounded the user process so Alpine exec timeouts leaked sleep children. Bound the post-cancel join, stop by container ID, write $$ then exec the step process, and cover keep_container plus shared-container exec timeout against a real daemon.
These files are new on this branch. Keep the SPDX license line only.
yohamta0
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First pass: one compatibility concern.
Native exec cancel now leaves argv unchanged. PID-file wrapping requires /bin/sh and a writable /tmp, which breaks distroless and read-only images. On Linux, cancel signals the exec PID from ExecInspect. Harness can still set PIDFile when it wants the wrap.
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Second pass: I found two remaining cancellation issues.
| if execStoppedWithin(cli, execID, 2*time.Second) { | ||
| return nil | ||
| if runtime.GOOS == "linux" { | ||
| _ = syscall.Kill(inspectResp.PID, syscall.SIGTERM) |
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ExecInspect.PID belongs to the Docker host, so syscall.Kill only works when Dagu shares the daemon's PID namespace. With remote Docker or containerized Dagu, it can signal an unrelated local process and leave the exec running. I reproduced the leak on Docker Desktop, and this also breaks Windows builds because syscall.Kill is undefined. Can cancellation stay on the daemon side?
| if canceledAt.IsZero() { | ||
| canceledAt = time.Now() | ||
| } | ||
| requestStop() |
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maxAfterCancel doesn't cover requestStop or inspect; the deadline is checked only after they return. Since both Docker calls use context.Background(), a stalled daemon can still hang Client.Run forever. Can they share a cleanup context with this deadline?
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Summary
timeout_seconly cancels the step context. NativeClient.Runthen polled withcontext.Background()and never calledContainerStop, so asleep 60with a 2s timeout waited for the sleep. Shared-containerExecleft the process running becauseTerminateOnCanceldefaulted to false.attachAndWaitreturns, honor ctx: stop the container once and join until it is gone.container:, multi-command steps, exec-into-existing) now passTerminateOnCancelplus a pid file, matching harness.Why
Harness already documented and worked around this hang. The native docker path did not. A cancelled step could leak a running container or an orphan exec inside a shared DAG container.
Validation
go test ./internal/runtime/builtin/docker/ -run 'TestWaitUntilContainerStopped|TestNativeExecOptions'go test -raceon the same testsalpine sleep 60with a 2s context finished in 5.63s (not 60s); container was auto-removedcancel.goline coverage:waitUntilContainerStopped100%,nativeExecOptions100%.User impact
Step
timeout_secnow stops dockerRuncontainers. Shared-container steps kill only the exec process, not the whole keepalive container.Summary by cubic
Stops Docker containers and shared-container execs when a step times out, preventing hangs and leaked processes. Previously
timeout_seconly canceled the step;Client.Runkept polling and shared-container execs left the process running.Client.Runnow honors the request context: waits viawaitUntilContainerStopped, on cancel callsstopContainerByID(SIGKILL), and bounds the post-cancel join.waitUntilContainerStopped,stopContainerByID, andnativeExecOptions;client.goand existing-container paths use them.nativeExecOptionsto setTerminateOnCancelwithout PID-file wrapping. On Linux, cancel signals the exec PID fromExecInspect; when a PID file is provided (by the harness), cancellation targets that PID.$$and execs the user command under/bin/sh, and is used only when a PID file is requested.auto_remove: falsethe container remains but is stopped; withauto_remove: trueit is removed.Written for commit 158f62b. Summary will update on new commits.
Summary by CodeRabbit