agent-framework/dotnet/samples/DurableAgents/ConsoleApps/11_WorkflowEvents

Single Workflow Console Sample

This sample demonstrates how to run a workflow as a durable orchestration from a console application using the Durable Task Framework. It showcases the durability aspect - if the process crashes mid-execution, the workflow can be resumed without re-executing completed activities.

Overview

The sample implements an order cancellation workflow with three executors, each with artificial delays to simulate real-world operations:

1. OrderLookup (2 seconds) - Looks up an order by its ID
2. OrderCancel (5 seconds) - Marks the order as cancelled
3. SendEmail (1 second) - Sends a cancellation confirmation email

Durability Demonstration

The key feature of Durable Task Framework is durability:

• Activity results are persisted: When an activity completes, its result is saved
• Orchestrations are replayed: On restart, the orchestration replays from the beginning
• Completed activities are skipped: The framework uses cached results for completed activities
• Failed activities are retried: If an activity was interrupted, it runs again
• Automatic resume: When the worker starts, it automatically picks up any pending work!

Try It Yourself

1. Start the application and enter an order ID (e.g., 12345)
2. Stop the app (Ctrl+C or stop debugging) during the OrderCancel activity (5 seconds)
3. Restart the application
4. Watch for automatic resume! The worker automatically picks up the interrupted workflow
5. Observe that OrderLookup is NOT re-executed (its result was cached)
6. OrderCancel restarts from the beginning (it didn't complete)
7. SendEmail runs after OrderCancel completes

The durability is completely automatic - no manual intervention needed!

Workflow Flow

User Input (Order ID)
       ?
       ?
???????????????????
?  OrderLookup    ?  ? 2 second delay (database lookup)
?  (2 seconds)    ?
???????????????????
         ?
         ?
???????????????????
?  OrderCancel    ?  ? 5 second delay - TRY INTERRUPTING HERE!
?  (5 seconds)    ?
???????????????????
         ?
         ?
???????????????????
?   SendEmail     ?  ? 1 second delay (email sending)
?  (1 second)     ?
???????????????????
         ?
         ?
      Result

Key Concepts Demonstrated

• ConfigureDurableWorkflows - Simplified API for registering workflows
• DurableExecution.RunAsync - Start a new workflow (similar to InProcessExecution)
• DurableRun - Handle to monitor and interact with a running workflow
• Automatic Resume - Interrupted workflows continue automatically on restart

Environment Setup

See the README.md file in the parent directory for more information on how to configure the environment, including how to install and run common sample dependencies.

Running the Sample

With the environment setup, you can run the sample:

cd dotnet/samples/DurableAgents/ConsoleApps/08_SingleWorkflow
dotnet run --framework net10.0

Sample Session

??????????????????????????????????????????????????????????????????????
?           Durable Workflow Console Sample                          ?
??????????????????????????????????????????????????????????????????????
?  This sample demonstrates durability in workflows.                 ?
?  Workflow: OrderLookup (2s) -> OrderCancel (5s) -> SendEmail (1s)  ?
??????????????????????????????????????????????????????????????????????

?? TIP: Stop the app during OrderCancel (5 seconds) to test durability!
   Restart the app - it will automatically resume from where it left off.

? Checking for pending workflows...

Enter an order ID to start a new workflow (or 'exit' to quit):

Order ID: 12345

Starting workflow for order '12345'...
Instance ID: abc123-def456-...

???????????????????????????????????????????????????????????????????
? [Activity] OrderLookup: Starting lookup for order '12345'
? [Activity] OrderLookup: Found order '12345' for customer 'Jerry'
???????????????????????????????????????????????????????????????????

???????????????????????????????????????????????????????????????????
? [Activity] OrderCancel: Starting cancellation for order '12345'
? [Activity] OrderCancel: ??  This takes 5 seconds - try Ctrl+C!
? [Activity] OrderCancel: Processing... 1/5 seconds
? [Activity] OrderCancel: Processing... 2/5 seconds
^C   <-- User stops the app here

[After restart...]

? Checking for pending workflows...

???????????????????????????????????????????????????????????????????
? [Activity] OrderCancel: Starting cancellation for order '12345'  <-- Auto-resumed!
? [Activity] OrderCancel: ??  This takes 5 seconds - try Ctrl+C!
? [Activity] OrderCancel: Processing... 1/5 seconds
...
? [Activity] OrderCancel: ? Order '12345' has been cancelled
???????????????????????????????????????????????????????????????????

???????????????????????????????????????????????????????????????????
? [Activity] SendEmail: Sending email to 'jerry@example.com'...
? [Activity] SendEmail: ? Email sent successfully!
???????????????????????????????????????????????????????????????????

Enter an order ID to start a new workflow (or 'exit' to quit):

Order ID: _

Notice that when resumed:

• OrderLookup was NOT re-executed (result was cached by Durable Task)
• OrderCancel restarted automatically (it was interrupted before completing)
• SendEmail ran normally after OrderCancel completed

Viewing Workflow State

You can view the state of the workflow in the Durable Task Scheduler dashboard:

1. Open your browser and navigate to http://localhost:8082
2. In the dashboard, you can view the state of the orchestration, including activity history and current state

Related Samples

• 01_SingleAgent - Single agent console sample
• 02_AgentOrchestration_Chaining - Agent chaining with durable orchestration
• 05_AgentOrchestration_HITL - Human-in-the-loop orchestration
• 09_Workflow - Azure Functions version of workflow hosting