webhook-notifications

Create a Zod schema spreading notificationResilienceFields, a defineAdminCollection handle, a composite (status, processedAt) Firestore index, a channel adapter calling defineNotificationPipeline, an ack-200 receiver route, a Cloud Tasks scheduler, and onTaskDispatched plus onSchedule functions.

The pipeline is enqueue-first by design: a notification that processes cleanly writes nothing, avoiding a write per event and giving the task queue rate control over provider API calls. Only failures are persisted so the sweep can re-drive them.

The failed lane retries hourly up to 5 attempts for work that errored, while the deferred lane retries daily up to 7 times when an external precondition (like an unconnected account) must clear first. Choose by who can clear the blockage, not severity.

The queue name must be region-qualified as locations/{region}/functions/{name}; without it the Admin SDK targets us-central1 and drops the task without error. The function export name must also exactly equal the queue constant.

Idempotency is the handler's job, not the receiver's — nothing dedups at enqueue time. Each process function must be safe to run twice, keyed by the provider's resource id, since delivery is at-least-once from both the provider and Cloud Tasks.

Yes, the tasks emulator works alongside the functions emulator, and the region-qualified queue name is correct for both production and emulator since firebase-admin 12.7.0. Do not pass opts.uri, and note scheduleDelaySeconds is ignored by the emulator's FIFO dispatch.