Error Handling - Temporal Nexus
Nexus Operations can return errors for a caller Workflow to handle. Errors from an asynchronous Operation's underlying Workflow propagate back to the caller.
Errors in Nexus handlers
Nexus handlers may return different error types. By default, handler errors are retryable unless they are:
- Application Failures explicitly marked as non-retryable.
- Nexus Operation errors that resolve an Operation as failed or canceled.
- Non-retryable Nexus errors.
When the caller's Nexus Machinery receives an error:
- Non-retryable - A NexusOperationFailed event is added to the caller's Event History.
- Retryable - The Nexus Machinery automatically retries. These errors surface in Pending Operations.
tip
Return a specific Nexus error type to avoid infinite retries. See errors in Nexus Operations for additional details.
Nexus error handling in caller Workflows
When a Nexus Operation fails, the caller receives a Nexus Operation Failure containing the operation name, token, and failure reason. The cause field indicates the type of error (for example, Application Error or Canceled Error).