Error handling - Temporal Go SDK feature guide

An Activity, or a Child Workflow, might fail, and you could handle errors differently based on the different error cases.

If the Activity returns an error as errors.New() or fmt.Errorf(), that error is converted into *temporal.ApplicationError.

If the Activity returns an error as temporal.NewNonRetryableApplicationError("error message", details), that error is returned as *temporal.ApplicationError.

There are other types of errors such as *temporal.TimeoutError, *temporal.CanceledError and *temporal.PanicError. Following is an example of what your error code might look like:

Here's an example of handling Activity errors within Workflow code that differentiates between different error types.

err := workflow.ExecuteActivity(ctx, YourActivity, ...).Get(ctx, nil)
if err != nil {
	var applicationErr *ApplicationError
	if errors.As(err, &applicationErr) {
		// retrieve error message
		fmt.Println(applicationError.Error())

		// handle Activity errors (created via NewApplicationError() API)
		var detailMsg string // assuming Activity return error by NewApplicationError("message", true, "string details")
		applicationErr.Details(&detailMsg) // extract strong typed details

		// handle Activity errors (errors created other than using NewApplicationError() API)
		switch applicationErr.Type() {
		case "CustomErrTypeA":
			// handle CustomErrTypeA
		case CustomErrTypeB:
			// handle CustomErrTypeB
		default:
			// newer version of Activity could return new errors that Workflow was not aware of.
		}
	}

	var canceledErr *CanceledError
	if errors.As(err, &canceledErr) {
		// handle cancellation
	}

	var timeoutErr *TimeoutError
	if errors.As(err, &timeoutErr) {
		// handle timeout, could check timeout type by timeoutErr.TimeoutType()
        switch err.TimeoutType() {
        case commonpb.ScheduleToStart:
                // Handle ScheduleToStart timeout.
        case commonpb.StartToClose:
                // Handle StartToClose timeout.
        case commonpb.Heartbeat:
                // Handle heartbeat timeout.
        default:
        }
	}

	var panicErr *PanicError
	if errors.As(err, &panicErr) {
		// handle panic, message and call stack are available by panicErr.Error() and panicErr.StackTrace()
	}
}