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API & Integration

The difference between payment webhook and API poll

Payment webhooks push status updates to your system immediately when events occur, while API polling requires your system to repeatedly query for status changes. Webhooks deliver real-time notifications, whereas polling creates delays and consumes unnecessary resources.

Why It Matters

Webhooks reduce infrastructure costs by 60-80% compared to polling by eliminating constant API calls. They provide status updates within 200-500 milliseconds versus 30-60 second polling intervals, enabling faster customer notifications and reducing abandoned checkout rates by 15-25%. Polling can consume 10,000+ unnecessary API calls per day for high-volume merchants, increasing operational costs and hitting rate limits.

How It Works in Practice

  1. 1Configure webhook endpoints in your payment processor dashboard with authentication tokens
  2. 2Register specific event types like payment_succeeded, payment_failed, or refund_processed
  3. 3Receive instant HTTP POST notifications to your endpoint when payment events occur
  4. 4Validate webhook signatures to ensure authenticity and prevent spoofing attacks
  5. 5Implement idempotency checks to handle duplicate webhook deliveries gracefully
  6. 6Fall back to API polling as backup when webhook delivery fails after 3-5 retry attempts

Common Pitfalls

PCI DSS compliance requires webhook endpoints to use HTTPS and validate all incoming requests properly

Webhook delivery failures occur in 2-5% of cases, requiring robust retry logic and fallback polling mechanisms

Idempotency violations can cause duplicate transaction processing when webhooks are delivered multiple times

Key Metrics

MetricTargetFormula
Webhook Delivery Success Rate>98%Successful webhook deliveries / Total webhook attempts × 100
Average Event Processing Time<500msTime from payment event to application processing completion
API Call Reduction>70%(Polling calls before webhooks - Current polling calls) / Polling calls before webhooks × 100

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