Add Python Tour of Restate (#444)

.github/workflows/pre-release.yml

@@ -11,6 +11,10 @@ on:
         description: "sdk-typescript version (without prepending v)."
         required: false
         type: string
+      sdkPythonVersion:
+        description: "sdk-python version (without prepending v)."
+        required: false
+        type: string
       sdkJavaVersion:
         description: "sdk-java version (without prepending v)."
         required: false
@@ -89,6 +93,14 @@ jobs:
           field: TYPESCRIPT_SDK_VERSION
           value: ${{ inputs.sdkTypescriptVersion }}
 
+      - name: Update restate.config.json with new Python sdk version
+        uses: jossef/[email protected]
+        if: ${{ inputs.sdkPythonVersion != '' }}
+        with:
+          file: restate.config.json
+          field: PYTHON_SDK_VERSION
+          value: ${{ inputs.sdkPythonVersion }}
+
       - name: Update restate.config.json with new Java sdk version
         uses: jossef/[email protected]
         if: ${{ inputs.sdkJavaVersion != '' }}
@@ -109,6 +121,26 @@ jobs:
       - name: Compile TypeScript code snippets
         run: npm install --prefix code_snippets/ts && npm run build --prefix code_snippets/ts
 
+      # Upgrade Python code snippets if new version is provided
+      - name: Upgrade Python Restate SDK
+        if: github.event.inputs.sdkPythonVersion != ''
+        run: sed -i 's/restate_sdk==[0-9A-Za-z.-]*/restate_sdk=="${{ inputs.sdkPythonVersion }}"/' "code_snippets/python/requirements.txt"
+
+      # Test if Python code snippets compile
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+      - name: Install dependencies and check Python code snippets
+        run: |
+          cd code_snippets/python
+          python3 -m venv .venv
+          source .venv/bin/activate
+          pip install -r requirements.txt
+          pip install mypy
+          python3 -m mypy .
+          deactivate
+
       # Upgrade Java code snippets if new version is provided
       - name: Find and replace restateVersion in build.gradle.kts for Java code snippets
         if: ${{ inputs.sdkJavaVersion != '' }}

.github/workflows/test-build.yml

@@ -40,6 +40,24 @@ jobs:
           exit 1
           fi
 
+          
+      # Setup Python
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
+      # Test if Python code snippets compile
+      - name: Install dependencies and check Python code snippets
+        run: |
+          cd code_snippets/python
+          python3 -m venv .venv
+          source .venv/bin/activate
+          pip install -r requirements.txt
+          pip install mypy
+          python3 -m mypy .
+          deactivate
+
       # Setup Java
       - uses: actions/setup-java@v3
         with:

.gitignore

@@ -23,3 +23,4 @@ yarn-error.log*
 .yarn
 /code_snippets/ts/node_modules/
 /code_snippets/ts/dist/
+/code_snippets/python/venv/

code_snippets/python/requirements.txt

@@ -0,0 +1,2 @@
+restate_sdk==0.2.1
+hypercorn

code_snippets/python/src/get_started/auxiliary/email_client.py

@@ -0,0 +1,20 @@
+# Copyright (c) 2024 - Restate Software, Inc., Restate GmbH
+#
+# This file is part of the Restate examples,
+# which is released under the MIT license.
+#
+# You can find a copy of the license in the file LICENSE
+# in the root directory of this repository or package or at
+# https://github.com/restatedev/examples/
+
+class EmailClient:
+
+    def notify_user_of_payment_success(self, user_id: str):
+        print(f"Notifying user {user_id} of payment success")
+        # send the email
+        return True
+
+    def notify_user_of_payment_failure(self, user_id: str):
+        print(f"Notifying user {user_id} of payment failure")
+        # send the email
+        return True

code_snippets/python/src/get_started/auxiliary/payment_client.py

@@ -0,0 +1,28 @@
+# Copyright (c) 2024 - Restate Software, Inc., Restate GmbH
+#
+# This file is part of the Restate examples,
+# which is released under the MIT license.
+#
+# You can find a copy of the license in the file LICENSE
+# in the root directory of this repository or package or at
+# https://github.com/restatedev/examples/
+
+class PaymentClient:
+
+    def __init__(self):
+        self.i = 0
+
+    async def call(self, idempotency_key: str | None, amount: float) -> bool:
+        print(f"Payment call succeeded for idempotency key {idempotency_key} and amount {amount}")
+        # do the call
+        return True
+
+    async def failing_call(self, idempotency_key: str, amount: float) -> bool:
+        if self.i >= 2:
+            print(f"Payment call succeeded for idempotency key {idempotency_key} and amount {amount}")
+            i = 0
+            return True
+        else:
+            print(f"Payment call failed for idempotency key {idempotency_key} and amount {amount}. Retrying...")
+            self.i += 1
+            raise Exception("Payment call failed")

code_snippets/python/src/get_started/checkout.py

@@ -0,0 +1,29 @@
+import uuid
+
+from restate import Service, ObjectContext
+
+from auxiliary.email_client import EmailClient
+from auxiliary.payment_client import PaymentClient
+from tour import Order
+
+payment_client = PaymentClient()
+email_client = EmailClient()
+
+checkout = Service("CheckoutService")
+
+
+# <start_checkout>
+@checkout.handler()
+async def handle(ctx: ObjectContext, order: Order) -> bool:
+    # withClass highlight-line
+    total_price = len(order['tickets']) * 40
+
+    idempotency_key = await ctx.run("idempotency_key", lambda: str(uuid.uuid4()))
+
+    # withClass(1:3) highlight-line
+    async def pay():
+        return await payment_client.call(idempotency_key, total_price)
+    success = await ctx.run("payment", pay)
+
+    return success
+# <end_checkout>

code_snippets/python/src/get_started/tour.py

@@ -0,0 +1,67 @@
+# Copyright (c) 2024 - Restate Software, Inc., Restate GmbH
+#
+# This file is part of the Restate examples,
+# which is released under the MIT license.
+#
+# You can find a copy of the license in the file LICENSE
+# in the root directory of this repository or package or at
+# https://github.com/restatedev/examples/
+import uuid
+from datetime import timedelta
+from typing import TypedDict, List
+
+from restate import VirtualObject
+from restate.context import ObjectContext, Serde
+from restate.service import Service
+
+from auxiliary.email_client import EmailClient
+from auxiliary.payment_client import PaymentClient
+
+cart = VirtualObject("CartObject")
+
+
+@cart.handler()
+async def my_handler(ctx: ObjectContext, order: str) -> bool:
+    ticket_id = ""
+
+    # <start_sleep>
+    await ctx.sleep(delta=timedelta(minutes=15))
+    # <end_sleep>
+
+    # <start_sleep_and_send>
+    await ctx.sleep(delta=timedelta(minutes=15))
+    ctx.object_send(unreserve, key=ticket_id, arg=None)
+    # <end_sleep_and_send>
+
+    return True
+
+
+ticket = VirtualObject("TicketObject")
+
+
+@ticket.handler()
+async def unreserve(ctx: ObjectContext) -> bool:
+    return True
+
+
+class Order(TypedDict):
+    user_id: str
+    tickets: List[str]
+
+
+checkout = Service("CheckoutService")
+
+
+# <start_uuid>
+@checkout.handler()
+async def handle(ctx: ObjectContext, order: Order) -> bool:
+    # withClass(1:3) highlight-line
+    idempotency_key = await ctx.run("idempotency_key", lambda: str(uuid.uuid4()))
+    print("My idempotency key is: ", idempotency_key)
+    raise Exception("Something happened!")
+
+    return True
+# <end_uuid>
+
+
+

code_snippets/ts/src/get_started/tour.ts

@@ -49,7 +49,7 @@ const secondCheckoutService = restate.service({
       const totalPrice = request.tickets.length * 40;
 
       const idempotencyKey = ctx.rand.uuidv4();
-      // withClass highlight-line
+      // withClass(1:3) highlight-line
       const success = await ctx.run(() =>
         PaymentClient.get().call(idempotencyKey, totalPrice)
       );