workflow-info

Workflow Info Sample

This sample demonstrates how to access workflow information during workflow execution, specifically the history length.

What it demonstrates

• Using workflow.InstanceExecutionDetails(ctx) to access workflow metadata
• Tracking how the workflow history grows as events are added
• Accessing the HistoryLength field of WorkflowInstanceExecutionDetails

Running the sample

go run .

Expected Output

You should see log messages showing the history length increasing as the workflow executes:

Workflow started historyLength=2
Activity executed
After activity execution historyLength=5
Activity executed
After second activity historyLength=8
Workflow completed successfully!

How it works

The WorkflowInstanceExecutionDetails struct contains information about the current workflow execution. Currently it provides:

• HistoryLength: The number of events in the workflow history at the current point in execution

The history length includes all events that have been added to the workflow's event history, including:

• WorkflowExecutionStarted
• WorkflowTaskStarted
• ActivityScheduled
• ActivityCompleted
• TimerScheduled
• TimerFired
• And other workflow events

This can be useful for:

• Monitoring workflow complexity
• Making decisions based on how far the workflow has progressed
• Implementing custom limits or checkpointing logic
• Debugging and understanding workflow execution

Future extensions

The WorkflowInstanceExecutionDetails struct is designed to be extensible. Future additions might include:

• Execution duration
• Number of activities executed
• Number of retries
• Custom metadata