refactor: update python workflow example with daprWorkflowClient (#1101)

Signed-off-by: Eileen Yu <eileenylj@gmail.com>

Author: Eileen-Yu

workflows/python/sdk/README.md

@@ -34,7 +34,7 @@ cd ..
 name: Running this example
 expected_stdout_lines:
   - "There are now 90 cars left in stock"
-  - "Workflow completed! Result: Completed"
+  - "Workflow completed!"
 output_match_mode: substring
 background: true
 timeout_seconds: 120

workflows/python/sdk/order-processor/app.py

@@ -4,54 +4,48 @@
 
 from dapr.clients import DaprClient
 from dapr.conf import settings
-from dapr.ext.workflow import WorkflowRuntime
+from dapr.ext.workflow import DaprWorkflowClient, WorkflowStatus
 
-from workflow import order_processing_workflow, notify_activity, process_payment_activity, \
-    verify_inventory_activity, update_inventory_activity, requst_approval_activity
+from workflow import wfr, order_processing_workflow
 from model import InventoryItem, OrderPayload
 
 store_name = "statestore"
-workflow_component = "dapr"
 workflow_name = "order_processing_workflow"
 default_item_name = "cars"
 
 class WorkflowConsoleApp:    
     def main(self):
         print("*** Welcome to the Dapr Workflow console app sample!", flush=True)
         print("*** Using this app, you can place orders that start workflows.", flush=True)
+        
+        wfr.start()
         # Wait for the sidecar to become available
         sleep(5)
 
-        workflowRuntime = WorkflowRuntime(settings.DAPR_RUNTIME_HOST, settings.DAPR_GRPC_PORT)
-        workflowRuntime.register_workflow(order_processing_workflow)
-        workflowRuntime.register_activity(notify_activity)
-        workflowRuntime.register_activity(requst_approval_activity)
-        workflowRuntime.register_activity(verify_inventory_activity)
-        workflowRuntime.register_activity(process_payment_activity)
-        workflowRuntime.register_activity(update_inventory_activity)
-        workflowRuntime.start()
+        wfClient = DaprWorkflowClient()
+
+        baseInventory = {
+            "paperclip": InventoryItem("Paperclip", 5, 100),
+            "cars": InventoryItem("Cars", 15000, 100),
+            "computers": InventoryItem("Computers", 500, 100),
+        }
 
-        daprClient = DaprClient(address=f'{settings.DAPR_RUNTIME_HOST}:{settings.DAPR_GRPC_PORT}')
-        baseInventory = {}
-        baseInventory["paperclip"] = InventoryItem("Paperclip", 5, 100)
-        baseInventory["cars"] = InventoryItem("Cars", 15000, 100)
-        baseInventory["computers"] = InventoryItem("Computers", 500, 100)
 
+        daprClient = DaprClient(address=f'{settings.DAPR_RUNTIME_HOST}:{settings.DAPR_GRPC_PORT}')
         self.restock_inventory(daprClient, baseInventory)
 
         print("==========Begin the purchase of item:==========", flush=True)
         item_name = default_item_name
         order_quantity = 10
-
         total_cost = int(order_quantity) * baseInventory[item_name].per_item_cost
         order = OrderPayload(item_name=item_name, quantity=int(order_quantity), total_cost=total_cost)
+
         print(f'Starting order workflow, purchasing {order_quantity} of {item_name}', flush=True)
-        start_resp = daprClient.start_workflow(workflow_component=workflow_component,
-                                               workflow_name=workflow_name,
-                                               input=order)
-        _id = start_resp.instance_id
+        instance_id = wfClient.schedule_new_workflow(
+            workflow=order_processing_workflow, input=order.to_json())
+        _id = instance_id
 
-        def prompt_for_approval(daprClient: DaprClient):
+        def prompt_for_approval(wfClient: DaprWorkflowClient):
             """This is a helper function to prompt for approval.
             Not using the prompt here ACTUALLY, as quickstart validation is required to be automated.
             
@@ -65,9 +59,9 @@ def prompt_for_approval(daprClient: DaprClient):
                 if state.runtime_status.name == "COMPLETED":
                     return
                 if approved.lower() == "y":
-                    client.raise_workflow_event(instance_id=_id, event_name="manager_approval", data={'approval': True})
+                    wfClient.raise_workflow_event(instance_id=_id, event_name="manager_approval", data={'approval': True})
                 else:
-                    client.raise_workflow_event(instance_id=_id, event_name="manager_approval", data={'approval': False})
+                    wfClient.raise_workflow_event(instance_id=_id, event_name="manager_approval", data={'approval': False})
 
                 ## Additionally, you would need to import signal and define timeout_error:
                 # import signal
@@ -76,32 +70,32 @@ def prompt_for_approval(daprClient: DaprClient):
 
                 # signal.signal(signal.SIGALRM, timeout_error)
             """
-            daprClient.raise_workflow_event(instance_id=_id, workflow_component=workflow_component, 
-                                            event_name="manager_approval", event_data={'approval': True})
+            wfClient.raise_workflow_event(instance_id=_id, event_name="manager_approval", data={'approval': True})
 
         approval_seeked = False
         start_time = datetime.now()
         while True:
             time_delta = datetime.now() - start_time
-            state = daprClient.get_workflow(instance_id=_id, workflow_component=workflow_component)
+            state = wfClient.get_workflow_state(instance_id=_id)
+
             if not state:
                 print("Workflow not found!")  # not expected
-            elif state.runtime_status == "Completed" or\
-                    state.runtime_status == "Failed" or\
-                    state.runtime_status == "Terminated":
+                break
+
+            if state.runtime_status in {WorkflowStatus.COMPLETED, WorkflowStatus.FAILED, WorkflowStatus.TERMINATED}:
                 print(f'Workflow completed! Result: {state.runtime_status}', flush=True)
                 break
+
+
             if time_delta.total_seconds() >= 10:
-                state = daprClient.get_workflow(instance_id=_id, workflow_component=workflow_component)
-                if total_cost > 50000 and (
-                    state.runtime_status != "Completed" or 
-                    state.runtime_status != "Failed" or
-                    state.runtime_status != "Terminated"
-                    ) and not approval_seeked:
+                state = wfClient.get_workflow_state(instance_id=_id)
+                if total_cost > 50000 and state not in {WorkflowStatus.COMPLETED, WorkflowStatus.FAILED, WorkflowStatus.TERMINATED} and not approval_seeked:
                     approval_seeked = True
-                    threading.Thread(target=prompt_for_approval(daprClient), daemon=True).start()
+                    threading.Thread(target=prompt_for_approval(wfClient), daemon=True).start()
+
+        wfr.shutdown()
+
 
-        print("Purchase of item is ", state.runtime_status, flush=True)
 
     def restock_inventory(self, daprClient: DaprClient, baseInventory):
         for key, item in baseInventory.items():

workflows/python/sdk/order-processor/workflow.py

@@ -1,9 +1,8 @@
-
 from datetime import timedelta
 import logging
 import json
 
-from dapr.ext.workflow import DaprWorkflowContext, WorkflowActivityContext, when_any
+from dapr.ext.workflow import DaprWorkflowContext, WorkflowActivityContext, WorkflowRuntime, when_any
 from dapr.clients import DaprClient
 from dapr.conf import settings
 
@@ -12,10 +11,13 @@
 
 store_name = "statestore"
 
+wfr = WorkflowRuntime()
+
 logging.basicConfig(level=logging.INFO)
 
 
-def order_processing_workflow(ctx: DaprWorkflowContext, order_payload_str: OrderPayload):
+@wfr.workflow(name="order_processing_workflow")
+def order_processing_workflow(ctx: DaprWorkflowContext, order_payload_str: str):
     """Defines the order processing workflow.
     When the order is received, the inventory is checked to see if there is enough inventory to
     fulfill the order. If there is enough inventory, the payment is processed and the inventory is
@@ -39,7 +41,7 @@ def order_processing_workflow(ctx: DaprWorkflowContext, order_payload_str: Order
         return OrderResult(processed=False)
 
     if order_payload["total_cost"] > 50000:
-        yield ctx.call_activity(requst_approval_activity, input=order_payload)
+        yield ctx.call_activity(request_approval_activity, input=order_payload)
         approval_task = ctx.wait_for_external_event("manager_approval")
         timeout_event = ctx.create_timer(timedelta(seconds=200))
         winner = yield when_any([approval_task, timeout_event])
@@ -76,15 +78,15 @@ def order_processing_workflow(ctx: DaprWorkflowContext, order_payload_str: Order
         message=f'Order {order_id} has completed!'))
     return OrderResult(processed=True)
 
-
+@wfr.activity(name="notify_activity")
 def notify_activity(ctx: WorkflowActivityContext, input: Notification):
     """Defines Notify Activity. This is used by the workflow to send out a notification"""
     # Create a logger
     logger = logging.getLogger('NotifyActivity')
     logger.info(input.message)
 
 
-
+@wfr.activity(name="process_payment_activity")
 def process_payment_activity(ctx: WorkflowActivityContext, input: PaymentRequest):
     """Defines Process Payment Activity.This is used by the workflow to process a payment"""
     logger = logging.getLogger('ProcessPaymentActivity')
@@ -94,6 +96,7 @@ def process_payment_activity(ctx: WorkflowActivityContext, input: PaymentRequest
     logger.info(f'Payment for request ID {input.request_id} processed successfully')
 
 
+@wfr.activity(name="verify_inventory_activity")
 def verify_inventory_activity(ctx: WorkflowActivityContext,
                               input: InventoryRequest) -> InventoryResult:
     """Defines Verify Inventory Activity. This is used by the workflow to verify if inventory
@@ -117,6 +120,8 @@ def verify_inventory_activity(ctx: WorkflowActivityContext,
     return InventoryResult(False, None)
 
 
+
+@wfr.activity(name="update_inventory_activity")
 def update_inventory_activity(ctx: WorkflowActivityContext,
                               input: PaymentRequest) -> InventoryResult:
     """Defines Update Inventory Activity. This is used by the workflow to check if inventory
@@ -139,7 +144,9 @@ def update_inventory_activity(ctx: WorkflowActivityContext,
         logger.info(f'There are now {new_quantity} {input.item_being_purchased} left in stock')
 
 
-def requst_approval_activity(ctx: WorkflowActivityContext,
+
+@wfr.activity(name="request_approval_activity")
+def request_approval_activity(ctx: WorkflowActivityContext,
                              input: OrderPayload):
     """Defines Request Approval Activity. This is used by the workflow to request approval
     for payment of an order. This activity is used only if the order total cost is greater than