Fix: Handle max retries in awaitWorkflowResult (#190)

Fixes #143

Author: vr-varad

dbos/errors.go

@@ -118,6 +118,14 @@ func newAwaitedWorkflowCancelledError(workflowID string) *DBOSError {
 	}
 }
 
+func newAwaitedWorkflowMaxStepRetriesExceeded(workflowID string) *DBOSError {
+	return &DBOSError{
+		Message:    fmt.Sprintf("Awaited workflow %s has exceeded the maximum number of step retries", workflowID),
+		Code:       MaxStepRetriesExceeded,
+		WorkflowID: workflowID,
+	}
+}
+
 func newWorkflowCancelledError(workflowID string) *DBOSError {
 	return &DBOSError{
 		Message: fmt.Sprintf("Workflow %s was cancelled", workflowID),

dbos/queues_test.go

@@ -365,12 +365,16 @@ func TestWorkflowQueues(t *testing.T) {
 		}
 
 		// Check the workflow completes
-		dlqCompleteEvent.Set()
 		for _, handle := range handles {
-			result, err := handle.GetResult()
-			require.NoError(t, err, "failed to get result from recovered workflow handle")
-			assert.Equal(t, "test-input", result, "expected result to be 'test-input'")
+
+			_, resultErr := handle.GetResult()
+
+			var dbosErr *DBOSError
+			require.ErrorAs(t, resultErr, &dbosErr, "expected error to be of type *DBOSError, got %T", resultErr)
+
+			assert.Equal(t, MaxStepRetriesExceeded, dbosErr.Code, "expected workflow to be in DLQ after max retries exceeded")
 		}
+		dlqCompleteEvent.Set()
 
 		require.True(t, queueEntriesAreCleanedUp(dbosCtx), "expected queue entries to be cleaned up after successive enqueues test")
 	})

dbos/system_database.go

@@ -1221,6 +1221,8 @@ func (s *sysDB) awaitWorkflowResult(ctx context.Context, workflowID string, poll
 			return outputString, errors.New(*errorStr)
 		case WorkflowStatusCancelled:
 			return outputString, newAwaitedWorkflowCancelledError(workflowID)
+		case WorkflowStatusMaxRecoveryAttemptsExceeded:
+			return outputString, newAwaitedWorkflowMaxStepRetriesExceeded(workflowID)
 		default:
 			time.Sleep(pollInterval)
 		}