internal stepInfo with *string step output

Author: maxdml

dbos/system_database.go

@@ -51,7 +51,7 @@ type systemDatabase interface {
 	// Steps
 	recordOperationResult(ctx context.Context, input recordOperationResultDBInput) error
 	checkOperationExecution(ctx context.Context, input checkOperationExecutionDBInput) (*recordedResult, error)
-	getWorkflowSteps(ctx context.Context, input getWorkflowStepsInput) ([]StepInfo, error)
+	getWorkflowSteps(ctx context.Context, input getWorkflowStepsInput) ([]stepInfo, error)
 
 	// Communication (special steps)
 	send(ctx context.Context, input WorkflowSendInput) error
@@ -1238,8 +1238,8 @@ type recordChildWorkflowDBInput struct {
 
 func (s *sysDB) recordChildWorkflow(ctx context.Context, input recordChildWorkflowDBInput) error {
 	query := fmt.Sprintf(`INSERT INTO %s.operation_outputs
-            (workflow_uuid, function_id, function_name, child_workflow_id, output)
-            VALUES ($1, $2, $3, $4, '')`, pgx.Identifier{s.schema}.Sanitize())
+            (workflow_uuid, function_id, function_name, child_workflow_id)
+            VALUES ($1, $2, $3, $4)`, pgx.Identifier{s.schema}.Sanitize())
 
 	var commandTag pgconn.CommandTag
 	var err error
@@ -1415,20 +1415,20 @@ func (s *sysDB) checkOperationExecution(ctx context.Context, input checkOperatio
 }
 
 // StepInfo contains information about a workflow step execution.
-type StepInfo struct {
-	StepID          int    // The sequential ID of the step within the workflow
-	StepName        string // The name of the step function
-	Output          any    // The output returned by the step (if any)
-	Error           error  // The error returned by the step (if any)
-	ChildWorkflowID string // The ID of a child workflow spawned by this step (if applicable)
+type stepInfo struct {
+	StepID          int     // The sequential ID of the step within the workflow
+	StepName        string  // The name of the step function
+	Output          *string // The output returned by the step (if any)
+	Error           error   // The error returned by the step (if any)
+	ChildWorkflowID string  // The ID of a child workflow spawned by this step (if applicable)
 }
 
 type getWorkflowStepsInput struct {
 	workflowID string
 	loadOutput bool
 }
 
-func (s *sysDB) getWorkflowSteps(ctx context.Context, input getWorkflowStepsInput) ([]StepInfo, error) {
+func (s *sysDB) getWorkflowSteps(ctx context.Context, input getWorkflowStepsInput) ([]stepInfo, error) {
 	query := fmt.Sprintf(`SELECT function_id, function_name, output, error, child_workflow_id
 			  FROM %s.operation_outputs
 			  WHERE workflow_uuid = $1
@@ -1440,9 +1440,9 @@ func (s *sysDB) getWorkflowSteps(ctx context.Context, input getWorkflowStepsInpu
 	}
 	defer rows.Close()
 
-	var steps []StepInfo
+	var steps []stepInfo
 	for rows.Next() {
-		var step StepInfo
+		var step stepInfo
 		var outputString *string
 		var errorString *string
 		var childWorkflowID *string

dbos/workflow.go

@@ -2144,6 +2144,14 @@ func ListWorkflows(ctx DBOSContext, opts ...ListWorkflowsOption) ([]WorkflowStat
 	return ctx.ListWorkflows(ctx, opts...)
 }
 
+type StepInfo struct {
+	StepID          int    // The sequential ID of the step within the workflow
+	StepName        string // The name of the step function
+	Output          any    // The output returned by the step (if any)
+	Error           error  // The error returned by the step (if any)
+	ChildWorkflowID string // The ID of a child workflow spawned by this step (if applicable)
+}
+
 func (c *dbosContext) GetWorkflowSteps(_ DBOSContext, workflowID string) ([]StepInfo, error) {
 	var loadOutput bool
 	if c.launched.Load() {
@@ -2156,12 +2164,12 @@ func (c *dbosContext) GetWorkflowSteps(_ DBOSContext, workflowID string) ([]Step
 		loadOutput: loadOutput,
 	}
 
-	var steps []StepInfo
+	var steps []stepInfo
 	var err error
 	workflowState, ok := c.Value(workflowStateKey).(*workflowState)
 	isWithinWorkflow := ok && workflowState != nil
 	if isWithinWorkflow {
-		steps, err = RunAsStep(c, func(ctx context.Context) ([]StepInfo, error) {
+		steps, err = RunAsStep(c, func(ctx context.Context) ([]stepInfo, error) {
 			return c.systemDB.getWorkflowSteps(ctx, getWorkflowStepsInput)
 		}, WithStepName("DBOS.getWorkflowSteps"))
 	} else {
@@ -2170,24 +2178,31 @@ func (c *dbosContext) GetWorkflowSteps(_ DBOSContext, workflowID string) ([]Step
 	if err != nil {
 		return nil, err
 	}
+	stepInfos := make([]StepInfo, len(steps))
+	for i, step := range steps {
+		stepInfos[i] = StepInfo{
+			StepID:          step.StepID,
+			StepName:        step.StepName,
+			Output:          step.Output,
+			Error:           step.Error,
+			ChildWorkflowID: step.ChildWorkflowID,
+		}
+	}
 
 	// Deserialize outputs if asked to
 	if loadOutput {
 		serializer := newGobSerializer[any]()
 		for i := range steps {
-			encodedOutput, ok := steps[i].Output.(*string)
-			if !ok {
-				return nil, fmt.Errorf("step output must be encoded string, got %T", steps[i].Output)
-			}
+			encodedOutput := steps[i].Output
 			decodedOutput, err := serializer.Decode(encodedOutput)
 			if err != nil {
 				return nil, fmt.Errorf("failed to deserialize step output for step %d: %w", steps[i].StepID, err)
 			}
-			steps[i].Output = decodedOutput
+			stepInfos[i].Output = decodedOutput
 		}
 	}
 
-	return steps, nil
+	return stepInfos, nil
 }
 
 // GetWorkflowSteps retrieves the execution steps of a workflow.