Result Verification

Result verification

Use verify when a command's exit status is insufficient to establish that its output is usable. A verifier can check file contents, query a database, or confirm that an uploaded object exists.

jobs:
  - name: export
    command: python export.py
    schedule: "0 * * * *"
    verify:
      command: python check_export.py
      timeout: 30

The verifier runs after the command passes its failsWhen rules. It inherits the job's environment, working directory, shell, privileges, secrets, and job API context. command accepts a shell string or an argument list. timeout defaults to 60 seconds and must be finite and positive. Set verify: null to clear an inherited verifier.

The verifier must exit with code zero. A nonzero exit, timeout, or launch failure fails the whole run, triggers its failure reporters, and follows its retry policy. Retrying runs the command and verifier again. A failed or canceled main command skips verification, and so does a workflow task whose command exits with one of its skipExitCodes. The verifier's timeout is separate from executionTimeout.

The timeout covers both the verifier process and its output streams. If the verifier exits but a child process still holds its stdout or stderr open at timeout, the run fails as a timeout. On timeout, the daemon cancels the verifier using the job's cancellation sequence, waits up to 30 seconds for each of the verifier's two output streams to close, and records the run with verification exit_code: -100 and fail_reason: "verification failed: command exited with code -100".

A cancel during verification applies the same sequence to the verifier, and the run has ended when the sequence finishes. Cancellation and killTimeout also covers a cancel that arrives before the verifier has a process, and the bound on output that a surviving process holds open.

The command's exit code remains intact. History includes a separate verification object with the check's outcome, exit code, timing, and diagnostics. Diagnostic text is redacted, retains at most 64 lines per stream, and is capped at 16384 characters per stream; oversized lines are discarded. output_truncated identifies truncation of retained output. For a job with resourceLimits, the verifier runs under the same caps in a cgroup or Job Object of its own, and limits holds its record (see verify checks and DAG tasks). Live output uses the verify.stdout and verify.stderr stream names. Report templates can inspect verification.

Executable DAG tasks accept the same verify block. Downstream tasks wait for verification to pass, and the task detail shows its result. Approval gates reject verify. A resource pool claim remains occupied through verification.