Templates/News Crawler Pipeline

News Crawler Pipeline

Data PipelineAdvancedOrg critical

Scheduled scraper pipeline with URL-frontier queuing, document storage, full-text indexing, and CDN-cached read API. Use for aggregators, content trackers, or data harvesting systems.

Recommended for: Web crawlers

7 nodes8 connectionsAsync processingLatency optimization

Use Case

Web crawlers, content aggregation, search indexing

Best Fit Scenarios

  • Web crawlers
  • Content aggregation
  • Search indexing

Stack Breakdown

SchedulerWorkersRedisMongoDBElasticsearchFastAPI

Architecture Layers

1Scheduling
2Worker Pool
3Queue
4Storage
5Search Index
6API

Components by Category

async

SchedulerRedis Queue

backend

Worker ServiceFastAPI

database

MongoDBElasticsearch

infra

CDN

Why This Topology Works

Scheduler distributes crawl jobs across workers via Redis queue. MongoDB stores raw content while Elasticsearch indexes for fast retrieval. CDN caches API responses.

Scaling Notes

Workers scale based on queue depth. MongoDB shards by domain for write distribution. Elasticsearch replicas handle search traffic.

Observability

Crawl success rate per domain. Queue processing latency. Elasticsearch indexing lag monitoring.

Typical Bottlenecks

  • Queue lag, retry storms, and DLQ growth during incidents
  • Service latency and timeout behavior on critical routes
  • Write amplification and query contention on primary stores

Async Flow and Reliability

User-facing operations remain synchronous while long-running work moves through queues or streams. Workers consume jobs independently with retry and failure isolation, improving resilience under burst load.

Upgrade Path

Harden each domain with clear ownership, enforce SLO budgets, and adopt multi-region or active-passive failover where downtime costs are high.

Operating Envelope

Complexity is marked as Advanced with an intended scope of Org critical. Use this as a planning baseline before adapting the template to your reliability and team constraints.