Simulate Payment Webhook for OpenTelemetry Traces in Jaeger

Simulate payment webhook events and trace them end-to-end in Jaeger with OpenTelemetry spans

This n8n automation workflow simulates a card charge via a webhook, then sends the run’s OpenTelemetry traces to a local Jaeger collector—so you can compare a successful charge against a deliberate failure. Built for Exercise 3 in the n8n Production AI Playbook on Audit & Trace, it requires no LLM credentials.

What this workflow does

• Receives webhook input: Accepts a POST request containing requestId and amount.
• Validates the Amount: An If node checks for invalid amounts; invalid requests are routed to Reject Request using a Stop and Error path.
• Normalizes input: An Edit Fields step converts the amount (e.g., 49.99) into cents for consistent “payment-like” processing.
• Simulates Charge vs Decline: Another If node routes requests with trigger_failure to a Decline Charge branch, which stops with an error card_declined.
• Captures success and responds: A capture step records the successful charge, and a Respond to Webhook returns it.

Use cases

• Verify OpenTelemetry trace visibility for webhook-driven automations in Jaeger.
• Test auditability by comparing a “success” run with a controlled failure (trigger_failure).
• Validate SaaS payment-like flows without calling real payment providers.

Technical details

• Integrations: OpenTelemetry tracing to Jaeger (via OTLP endpoint, e.g., Jaeger port 4318).
• Nodes used: Webhook, If, Edit Fields, Stop and Error, Respond to Webhook, plus supporting notes like Sticky Note.

Quick setup (Jaeger + n8n)

• Run Jaeger locally (Docker image jaegertracing/jaeger:2.20.0) and expose 4318.
• In n8n: Settings > OpenTelemetry: set the OTLP endpoint, sample rate to 1, turn off “Track published workflows only”, and enable tracing.
• Execute with: {"requestId":"REQ-3001","amount":49.99} and {"requestId":"REQ-3002","amount":49.99,"trigger_failure":true}. Inspect spans in Jaeger by searching n8n.execution.id.