n8n Circuit Breaker Webhook for Data Table API Protection

Prevent repeated API failures in n8n with a circuit breaker webhook + Data Table state

This n8n Circuit Breaker Webhook stops your workflows from hammering an unavailable downstream API. It tracks failures in an n8n Data Table, opens a “circuit” after consecutive errors, enforces a cooldown, and only allows a controlled half-open recovery attempt.

What this workflow does

• Checks permission to call: When your calling service sends a POST to /webhook/circuit-breaker-check with a service_key, the workflow determines whether the downstream call should proceed.
• Evaluates circuit state: It looks up the service’s circuit record in the service_circuits Data Table and uses the current state plus a cooldown window to decide: allow, block, or initiate a half-open trial.
• Half-open trial handling: When entering half-open, the workflow creates/updates the circuit record and responds with allow_request, the current state, and retry_after_seconds.
• Records outcomes: After an allowed call, your service posts to /webhook/circuit-breaker-result with service_key, success, and optional error.
• Closes or opens the circuit: On success it closes the circuit. On repeated failures (or half-open failure), it increments failure count, opens the circuit, and sets an open_until time.

Use cases

• Shield n8n automations from outages in a Data Table API or any downstream endpoint.
• Reduce workflow churn when a third-party service is intermittently failing.
• Implement a reliable retry strategy with cooldown and half-open recovery trials.

Technical details

• Webhook endpoints: /webhook/circuit-breaker-check and /webhook/circuit-breaker-result
• Storage: n8n Data Table named service_circuits
• Nodes used: Webhook, Data Table, Code, Switch, and Sticky Note

Setup: Create the service_circuits Data Table with the template columns (including service_key, state, failure_count, failure_threshold, and timestamp fields). Then copy both webhook URLs and configure your caller to use the two endpoints.