ext

Overview ¶

Package ext defines the extension system for Dispatch.

Extensions are notified of lifecycle events and can react to them — recording metrics, emitting webhooks, writing audit logs, etc. Each lifecycle hook is a separate interface so extensions opt in only to the events they care about.

Implementing an Extension ¶

type MyExtension struct{}

func (e *MyExtension) Name() string { return "my-extension" }

// Opt in to specific hooks by implementing their interfaces.
func (e *MyExtension) OnJobCompleted(ctx context.Context, j *job.Job, elapsed time.Duration) error {
    log.Printf("job %s completed in %s", j.ID, elapsed)
    return nil
}

Job Lifecycle Hooks ¶

• JobEnqueued — job was accepted into the queue
• JobStarted — worker began executing the job
• JobCompleted — job finished successfully
• JobFailed — job failed with no retries remaining
• JobRetrying — job failed but will be retried
• JobDLQ — job was moved to the dead letter queue
• JobCancelled: job reached cancelled

Workflow Lifecycle Hooks ¶

• WorkflowStarted — workflow run began
• WorkflowStepCompleted — a step finished successfully
• WorkflowStepFailed — a step failed
• WorkflowCompleted — workflow run finished successfully
• WorkflowFailed — workflow run failed terminally

Other Hooks ¶

• CronFired — a cron entry was triggered and a job was enqueued
• Shutdown — the dispatcher is shutting down gracefully

Operator Actions ¶

• OperatorActionObserver: an operator cancelled, retried, replayed, deleted, purged, toggled or triggered something through the engine. The Action carries the subject from WithActor as its Actor.

The Registry fans out each event to all registered extensions that implement the corresponding hook interface.

Package ext defines the extension system for Dispatch. Extensions are notified of lifecycle events (job enqueued, completed, failed, etc.) and can react to them — logging, metrics, tracing, etc.

Each lifecycle hook is a separate interface so extensions opt in only to the events they care about.