quickstarts/tutorials/workflow/csharp/monitor-pattern/README.md

Monitor Pattern

This tutorial demonstrates how to run a workflow in a loop. This can be used for recurring tasks that need to be executed on a certain frequency (e.g. a clean-up job that runs every hour). For more information on the monitor pattern see the Dapr docs.

Inspect the code

Open the MonitorWorkflow.cs file in the tutorials/workflow/csharp/monitor-pattern/Monitor folder. This file contains the definition for the workflow.

graph LR
   SW((Start
   Workflow))
   CHECK[CheckStatus]
   IF{Is Ready}
   TIMER[Wait for a period of time]
   NEW[Continue as a new instance]
   EW((End
   Workflow))
   SW --> CHECK
   CHECK --> IF
   IF -->|Yes| EW
   IF -->|No| TIMER
   TIMER --> NEW
   NEW --> SW

Run the tutorial

1. Use a terminal to navigate to the tutorials/workflow/csharp/monitor-pattern folder.

2. Build the project using the .NET CLI.

   dotnet build ./Monitor/
   

3. Use the Dapr CLI to run the Dapr Multi-App run file

   dapr run -f .
   

4. Use the POST request in the monitor.http file to start the workflow.

   The input for the workflow is an integer with the value 0.

5. Use the GET request in the monitor.http file to get the status of the workflow.

   The expected serialized output of the workflow is:

   "\"Status is healthy after checking 3 times.\""
   

   The actual number of checks can vary since some randomization is used in the CheckStatus activity.

6. Stop the Dapr Multi-App run process by pressing Ctrl+C.