demo_workflow

Example - Dapr Workflow Authoring

This document describes how to register a workflow and activities inside it and start running it. It demonstrates the following APIs:

• start_workflow: Start an instance of a workflow
• get_workflow: Get information on a single workflow
• terminate_workflow: Terminate or stop a particular instance of a workflow
• raise_event: Raise an event on a workflow
• pause_workflow: Pauses or suspends a workflow instance that can later be resumed
• resume_workflow: Resumes a paused workflow instance
• purge_workflow: Removes all metadata related to a specific workflow instance from the state store

Pre-requisites

• Dapr CLI and initialized environment
• Install Python 3.8+

Install requirements

You can install dapr SDK package using pip command:

pip3 install -r demo_workflow/requirements.txt

dapr run --app-id orderapp --app-protocol grpc --dapr-grpc-port 50001 --resources-path components --placement-host-address localhost:50005 -- python3 app.py

You should be able to see the following output:

== APP == Hi Counter!
== APP == New counter value is: 1!
== APP == New counter value is: 11!
== APP == Retry count value is: 0!
== APP == Retry count value is: 1! This print statement verifies retry
== APP == Appending 1 to child_orchestrator_string!
== APP == Appending a to child_orchestrator_string!
== APP == Appending a to child_orchestrator_string!
== APP == Appending 2 to child_orchestrator_string!
== APP == Appending b to child_orchestrator_string!
== APP == Appending b to child_orchestrator_string!
== APP == Appending 3 to child_orchestrator_string!
== APP == Appending c to child_orchestrator_string!
== APP == Appending c to child_orchestrator_string!
== APP == Get response from hello_world_wf after pause call: Suspended
== APP == Get response from hello_world_wf after resume call: Running
== APP == New counter value is: 111!
== APP == New counter value is: 1111!
== APP == Instance Successfully Purged
== APP == Get response from hello_world_wf after terminate call: Terminated
== APP == Get response from child_wf after terminate call: Terminated