API Interactions

The CRE SDK provides an HTTP client that allows your workflows to interact with external APIs. Use it to fetch offchain data, send results to other systems, or trigger external events.

Guides

• Making GET Requests: Learn how to fetch data from a public API using a GET request.
• Making POST Requests: Learn how to send data to an external endpoint using a POST request.
• Submitting Reports via HTTP: Learn how to submit cryptographically signed reports to an external HTTP endpoint.
• Verifying CRE Reports Offchain: Verify report signatures and read workflow metadata when receiving reports over HTTP or other offchain channels.

CRE reports over HTTP

A CRE report is a DON-signed package your workflow creates with runtime.report() (TypeScript) or runtime.GenerateReport() (Go). It bundles your encoded payload, workflow metadata, report context, and cryptographic signatures from the DON. See Key Terms: Report for the full definition, including how onchain delivery differs from HTTP.

A typical secure integration uses two parties:

1. Sender: a CRE workflow that runs your logic, signs a report, and POSTs it to a URL. See Submitting Reports via HTTP.
2. Receiver: your API or another CRE workflow that verifies the report before using the data. See Verifying CRE Reports Offchain.

The sender creates the report inside the workflow; the receiver must verify signatures before trusting the payload.