WorkflowEvent

WorkflowEvent Type - Individual event in workflow execution history

Audience: Programmer

The WorkflowEvent type represents a single event in a Temporal workflow's execution history. Each event captures a specific action or state change that occurred during workflow execution, providing a detailed audit trail of the workflow's progress.

Fields

Field	Type	Description
eventId	Int!	Sequential identifier for the event within the workflow history
eventTime	String!	ISO 8601 timestamp when the event occurred
eventType	String!	The type of event (e.g., WorkflowExecutionStarted, ActivityTaskScheduled)
extra	Map	Additional event-specific attributes and data

Service

This type is defined in the Workflow service.

Event Types

Temporal workflows generate various event types throughout their execution. Common event types include:

Workflow Lifecycle Events

Event Type	Description
EVENT_TYPE_WORKFLOW_EXECUTION_STARTED	Workflow execution has begun
EVENT_TYPE_WORKFLOW_EXECUTION_COMPLETED	Workflow completed successfully
EVENT_TYPE_WORKFLOW_EXECUTION_FAILED	Workflow failed with an error
EVENT_TYPE_WORKFLOW_EXECUTION_TIMED_OUT	Workflow exceeded its timeout
EVENT_TYPE_WORKFLOW_EXECUTION_CANCELED	Workflow was canceled
EVENT_TYPE_WORKFLOW_EXECUTION_TERMINATED	Workflow was forcefully terminated

Activity Events

Event Type	Description
EVENT_TYPE_ACTIVITY_TASK_SCHEDULED	Activity task has been scheduled
EVENT_TYPE_ACTIVITY_TASK_STARTED	Activity task execution started
EVENT_TYPE_ACTIVITY_TASK_COMPLETED	Activity task completed successfully
EVENT_TYPE_ACTIVITY_TASK_FAILED	Activity task failed
EVENT_TYPE_ACTIVITY_TASK_TIMED_OUT	Activity task exceeded its timeout

Timer Events

Event Type	Description
EVENT_TYPE_TIMER_STARTED	Timer has been started
EVENT_TYPE_TIMER_FIRED	Timer has fired
EVENT_TYPE_TIMER_CANCELED	Timer was canceled

Workflow Task Events

Event Type	Description
EVENT_TYPE_WORKFLOW_TASK_SCHEDULED	Workflow task has been scheduled
EVENT_TYPE_WORKFLOW_TASK_STARTED	Workflow task execution started
EVENT_TYPE_WORKFLOW_TASK_COMPLETED	Workflow task completed

Usage Example

Query Workflow Execution with History

query GetWorkflowHistory {
  workflowExecutions(
    where: {
      workflowID: "picking-order-12345"
    }
  ) {
    execution {
      workflowId
      id
    }
    type {
      name
    }
    status
    startTime
    closeTime
    historyLength
    history {
      eventId
      eventTime
      eventType
      extra
    }
  }
}

Query Recent Activity Events

query GetWorkflowActivities {
  workflowExecutions(
    where: {
      typeName: "PickingWorkflow"
      status: "RUNNING"
    }
  ) {
    execution {
      workflowId
    }
    memo {
      title
    }
    history {
      eventId
      eventTime
      eventType
      extra
    }
  }
}

Example Response

{
  "data": {
    "workflowExecutions": [
      {
        "execution": {
          "workflowId": "picking-order-12345",
          "id": "run-abc-123"
        },
        "type": {
          "name": "PickingWorkflow"
        },
        "status": "RUNNING",
        "startTime": "2024-01-15T10:30:00Z",
        "closeTime": null,
        "historyLength": 12,
        "history": [
          {
            "eventId": 1,
            "eventTime": "2024-01-15T10:30:00Z",
            "eventType": "EVENT_TYPE_WORKFLOW_EXECUTION_STARTED",
            "extra": {
              "workflowType": {
                "name": "PickingWorkflow"
              },
              "taskQueue": {
                "name": "picking-queue"
              },
              "input": null,
              "workflowExecutionTimeout": "3600s",
              "workflowRunTimeout": "3600s"
            }
          },
          {
            "eventId": 2,
            "eventTime": "2024-01-15T10:30:00Z",
            "eventType": "EVENT_TYPE_WORKFLOW_TASK_SCHEDULED",
            "extra": {
              "taskQueue": {
                "name": "picking-queue"
              },
              "startToCloseTimeout": "10s"
            }
          },
          {
            "eventId": 3,
            "eventTime": "2024-01-15T10:30:01Z",
            "eventType": "EVENT_TYPE_WORKFLOW_TASK_STARTED",
            "extra": {
              "scheduledEventId": "2",
              "identity": "worker-1@picking-service"
            }
          },
          {
            "eventId": 4,
            "eventTime": "2024-01-15T10:30:01Z",
            "eventType": "EVENT_TYPE_WORKFLOW_TASK_COMPLETED",
            "extra": {
              "scheduledEventId": "2",
              "startedEventId": "3"
            }
          },
          {
            "eventId": 5,
            "eventTime": "2024-01-15T10:30:01Z",
            "eventType": "EVENT_TYPE_ACTIVITY_TASK_SCHEDULED",
            "extra": {
              "activityId": "1",
              "activityType": {
                "name": "ValidatePickingOrder"
              },
              "taskQueue": {
                "name": "picking-queue"
              },
              "scheduleToCloseTimeout": "300s",
              "scheduleToStartTimeout": "60s",
              "startToCloseTimeout": "240s"
            }
          },
          {
            "eventId": 6,
            "eventTime": "2024-01-15T10:30:02Z",
            "eventType": "EVENT_TYPE_ACTIVITY_TASK_STARTED",
            "extra": {
              "scheduledEventId": "5",
              "identity": "worker-2@picking-service"
            }
          },
          {
            "eventId": 7,
            "eventTime": "2024-01-15T10:30:05Z",
            "eventType": "EVENT_TYPE_ACTIVITY_TASK_COMPLETED",
            "extra": {
              "scheduledEventId": "5",
              "startedEventId": "6",
              "result": null
            }
          }
        ]
      }
    ]
  }
}

JavaScript Example

// Fetch workflow history and analyze events
const response = await client.query({
  query: gql`
    query GetWorkflowHistory($workflowId: String!) {
      workflowExecutions(
        where: { workflowID: $workflowId }
      ) {
        execution {
          workflowId
          id
        }
        status
        history {
          eventId
          eventTime
          eventType
          extra
        }
      }
    }
  `,
  variables: {
    workflowId: "picking-order-12345"
  }
});

const workflow = response.data.workflowExecutions[0];
const history = workflow.history;

// Filter for activity events
const activityEvents = history.filter(event =>
  event.eventType.includes('ACTIVITY')
);

// Find failed activities
const failedActivities = history.filter(event =>
  event.eventType === 'EVENT_TYPE_ACTIVITY_TASK_FAILED'
);

// Calculate workflow duration from events
const startEvent = history.find(e =>
  e.eventType === 'EVENT_TYPE_WORKFLOW_EXECUTION_STARTED'
);
const endEvent = history.find(e =>
  e.eventType === 'EVENT_TYPE_WORKFLOW_EXECUTION_COMPLETED'
);

if (startEvent && endEvent) {
  const duration = new Date(endEvent.eventTime) - new Date(startEvent.eventTime);
  console.log(`Workflow completed in ${duration}ms`);
}

Use Cases

Debugging Failed Workflows

Query the history to identify where a workflow failed:

query DebugFailedWorkflow {
  workflowExecutions(
    where: {
      workflowID: "failed-workflow-123"
      status: "FAILED"
    }
  ) {
    execution {
      workflowId
    }
    history {
      eventId
      eventTime
      eventType
      extra
    }
  }
}

Monitoring Activity Performance

Analyze activity durations by examining the time between SCHEDULED, STARTED, and COMPLETED events.

Audit Trail

The history provides a complete audit trail of all actions taken during workflow execution, useful for compliance and debugging.

Related Types

• WorkflowExecutionInfo - Parent type containing the history field

• WorkflowMemo - Structured workflow metadata

• TemporalMetadata - Key-value metadata for search attributes

• Workflow - Workflow definition type

Notes

• The eventId field is sequential within a workflow execution, starting at 1

• Event times are in ISO 8601 format (RFC3339)

• The extra field contains event-specific attributes that vary by event type

• History events are ordered chronologically by eventId

• Large workflows may have extensive histories; use historyLength to gauge size before fetching

• The history is fetched directly from Temporal and reflects the complete execution state

• Event types follow Temporal's naming convention with the EVENT_TYPE_ prefix