Broadcasting a single published article to hundreds of external subscriber endpoints requires decoupled background worker queues and resilient retry strategies.
1. Resilient Fan-Out Pipeline
- Decoupled Ingestion: Express API routes accept publish requests, validate HMAC signatures, and push payloads directly into a Redis/RabbitMQ queue.
- Worker Pool Scaling: Asynchronous Node.js workers process batches with concurrency controls to prevent downstream server saturation.
- Exponential Backoff: Retrying failed subscriber webhooks at intervals (1m, 5m, 15m, 1h) before isolating bad endpoints into dead-letter storage.