Merge pull request #20 from mfateev/bookingsaga

Added bookingsaga sample

Author: mfateev

README.md

@@ -80,6 +80,8 @@ of details about the execution history.
 Each sample has specific requirements for running it. The following sections contain information about
 how to run each of the samples after you've built them using the preceding instructions.
 
+Don't forget to check unit tests found under src/test/java!
+
 ### Hello World
 
 To run the hello world samples:
@@ -106,4 +108,15 @@ execute together, we recommend that you run more than one instance of this worke
 The second command starts workflows. Each invocation starts a new workflow execution.
 
     ./gradlew -q execute -PmainClass=com.uber.cadence.samples.fileprocessing.FileProcessingStarter
+    
+### Trip Booking
+
+Cadence implementation of the [Camunda BPMN trip booking example](https://github.com/berndruecker/trip-booking-saga-java)
+
+Demonstrates Cadence approach to SAGA.
+
+To run:
+
+    ./gradlew -q execute -PmainClass=com.uber.cadence.samples.bookingsaga.TripBookingSaga
+
 

src/main/java/com/uber/cadence/samples/bookingsaga/README.md

@@ -0,0 +1,7 @@
+## Saga example: trip booking
+
+Cadence implementation of the [Camunda BPMN trip booking example](https://github.com/berndruecker/trip-booking-saga-java)
+
+Demonstrates Cadence approach to SAGA.
+
+Don't forget to check TripBookingWorkflowTest in src/test/java/com/uber/cadence/samples/bookingsaga.

src/main/java/com/uber/cadence/samples/bookingsaga/TripBookingActivities.java

@@ -0,0 +1,60 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file is distributed on
+ *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package com.uber.cadence.samples.bookingsaga;
+
+public interface TripBookingActivities {
+
+  /**
+   * @param name customer name
+   * @return reservationID
+   */
+  String reserveCar(String name);
+
+  /**
+   * @param name customer name
+   * @return reservationID
+   */
+  String bookFlight(String name);
+
+  /**
+   * @param name customer name
+   * @return reservationID
+   */
+  String bookHotel(String name);
+
+  /**
+   * @param name customer name
+   * @param reservationID id returned by bookFlight
+   * @return cancellationConfirmationID
+   */
+  String cancelFlight(String reservationID, String name);
+
+  /**
+   * @param name customer name
+   * @param reservationID id returned by bookHotel
+   * @return cancellationConfirmationID
+   */
+  String cancelHotel(String reservationID, String name);
+
+  /**
+   * @param name customer name
+   * @param reservationID id returned by reserveCar
+   * @return cancellationConfirmationID
+   */
+  String cancelCar(String reservationID, String name);
+}

src/main/java/com/uber/cadence/samples/bookingsaga/TripBookingActivitiesImpl.java

@@ -0,0 +1,58 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file is distributed on
+ *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package com.uber.cadence.samples.bookingsaga;
+
+import java.util.UUID;
+
+public class TripBookingActivitiesImpl implements TripBookingActivities {
+  @Override
+  public String reserveCar(String name) {
+    System.out.println("reserve car for '" + name + "'");
+    return UUID.randomUUID().toString();
+  }
+
+  @Override
+  public String bookFlight(String name) {
+    System.out.println("failing to book flight for '" + name + "'");
+    throw new RuntimeException("Flight booking did not work");
+  }
+
+  @Override
+  public String bookHotel(String name) {
+    System.out.println("booking hotel for '" + name + "'");
+    return UUID.randomUUID().toString();
+  }
+
+  @Override
+  public String cancelFlight(String reservationID, String name) {
+    System.out.println("cancelling flight reservation '" + reservationID + "' for '" + name + "'");
+    return UUID.randomUUID().toString();
+  }
+
+  @Override
+  public String cancelHotel(String reservationID, String name) {
+    System.out.println("cancelling hotel reservation '" + reservationID + "' for '" + name + "'");
+    return UUID.randomUUID().toString();
+  }
+
+  @Override
+  public String cancelCar(String reservationID, String name) {
+    System.out.println("cancelling car reservation '" + reservationID + "' for '" + name + "'");
+    return UUID.randomUUID().toString();
+  }
+}

src/main/java/com/uber/cadence/samples/bookingsaga/TripBookingSaga.java

@@ -0,0 +1,63 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file is distributed on
+ *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package com.uber.cadence.samples.bookingsaga;
+
+import static com.uber.cadence.samples.common.SampleConstants.DOMAIN;
+
+import com.uber.cadence.client.WorkflowClient;
+import com.uber.cadence.client.WorkflowException;
+import com.uber.cadence.worker.Worker;
+
+public class TripBookingSaga {
+
+  static final String TASK_LIST = "TripBooking";
+
+  public static void main(String[] args) {
+
+    // Get worker to poll the common task list.
+    Worker.Factory factory = new Worker.Factory(DOMAIN);
+    final Worker workerForCommonTaskList = factory.newWorker(TASK_LIST);
+    workerForCommonTaskList.registerWorkflowImplementationTypes(TripBookingWorkflowImpl.class);
+    TripBookingActivities tripBookingActivities = new TripBookingActivitiesImpl();
+    workerForCommonTaskList.registerActivitiesImplementations(tripBookingActivities);
+
+    // Start all workers created by this factory.
+    factory.start();
+    System.out.println("Worker started for task list: " + TASK_LIST);
+
+    WorkflowClient workflowClient = WorkflowClient.newInstance(DOMAIN);
+
+    // now we can start running instances of our saga - its state will be persisted
+    TripBookingWorkflow trip1 = workflowClient.newWorkflowStub(TripBookingWorkflow.class);
+    try {
+      trip1.bookTrip("trip1");
+    } catch (WorkflowException e) {
+      // Expected
+      e.printStackTrace();
+    }
+
+    try {
+      TripBookingWorkflow trip2 = workflowClient.newWorkflowStub(TripBookingWorkflow.class);
+      trip2.bookTrip("trip2");
+    } catch (WorkflowException e) {
+      e.printStackTrace();
+    }
+
+    System.exit(0);
+  }
+}

src/main/java/com/uber/cadence/samples/bookingsaga/TripBookingWorkflow.java

@@ -0,0 +1,28 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file is distributed on
+ *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package com.uber.cadence.samples.bookingsaga;
+
+import static com.uber.cadence.samples.bookingsaga.TripBookingSaga.TASK_LIST;
+
+import com.uber.cadence.workflow.WorkflowMethod;
+
+public interface TripBookingWorkflow {
+
+  @WorkflowMethod(executionStartToCloseTimeoutSeconds = 3600, taskList = TASK_LIST)
+  void bookTrip(String name);
+}

src/main/java/com/uber/cadence/samples/bookingsaga/TripBookingWorkflowImpl.java

@@ -0,0 +1,52 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file is distributed on
+ *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package com.uber.cadence.samples.bookingsaga;
+
+import com.uber.cadence.activity.ActivityOptions;
+import com.uber.cadence.workflow.ActivityException;
+import com.uber.cadence.workflow.Saga;
+import com.uber.cadence.workflow.Workflow;
+import java.time.Duration;
+
+public class TripBookingWorkflowImpl implements TripBookingWorkflow {
+
+  private final ActivityOptions options =
+      new ActivityOptions.Builder().setScheduleToCloseTimeout(Duration.ofHours(1)).build();
+  private final TripBookingActivities activities =
+      Workflow.newActivityStub(TripBookingActivities.class, options);
+
+  @Override
+  public void bookTrip(String name) {
+    // Configure SAGA to run compensation activities in parallel
+    Saga.Options sagaOptions = new Saga.Options.Builder().setParallelCompensation(true).build();
+    Saga saga = new Saga(sagaOptions);
+    try {
+      String carReservationID = activities.reserveCar(name);
+      saga.addCompensation(activities::cancelCar, carReservationID, name);
+
+      String hotelReservationID = activities.bookHotel(name);
+      saga.addCompensation(activities::cancelHotel, hotelReservationID, name);
+
+      String flightReservationID = activities.bookFlight(name);
+      saga.addCompensation(activities::cancelFlight, flightReservationID, name);
+    } catch (ActivityException e) {
+      saga.compensate();
+      throw e;
+    }
+  }
+}

src/test/java/com/uber/cadence/samples/bookingsaga/TripBookingWorkflowTest.java

@@ -0,0 +1,96 @@
+/*
+ *  Copyright 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"). You may not
+ *  use this file except in compliance with the License. A copy of the License is
+ *  located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ *  or in the "license" file accompanying this file. This file is distributed on
+ *  an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package com.uber.cadence.samples.bookingsaga;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import com.uber.cadence.client.WorkflowClient;
+import com.uber.cadence.client.WorkflowException;
+import com.uber.cadence.testing.TestWorkflowEnvironment;
+import com.uber.cadence.worker.Worker;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class TripBookingWorkflowTest {
+
+  private TestWorkflowEnvironment testEnv;
+  private Worker worker;
+  private WorkflowClient workflowClient;
+
+  @Before
+  public void setUp() {
+    testEnv = TestWorkflowEnvironment.newInstance();
+    worker = testEnv.newWorker(TripBookingSaga.TASK_LIST);
+    worker.registerWorkflowImplementationTypes(TripBookingWorkflowImpl.class);
+
+    workflowClient = testEnv.newWorkflowClient();
+  }
+
+  @After
+  public void tearDown() {
+    testEnv.close();
+  }
+
+  /**
+   * Not very useful test that validates that the default activities cause workflow to fail. See
+   * other tests on using mocked activities to test SAGA logic.
+   */
+  @Test
+  public void testTripBookingFails() {
+    worker.registerActivitiesImplementations(new TripBookingActivitiesImpl());
+    testEnv.start();
+
+    TripBookingWorkflow workflow = workflowClient.newWorkflowStub(TripBookingWorkflow.class);
+    try {
+      workflow.bookTrip("trip1");
+      fail("unreachable");
+    } catch (WorkflowException e) {
+      assertEquals("Flight booking did not work", e.getCause().getCause().getMessage());
+    }
+  }
+
+  /** Unit test workflow logic using mocked activities. */
+  @Test
+  public void testSAGA() {
+    TripBookingActivities activities = mock(TripBookingActivities.class);
+    when(activities.bookHotel("trip1")).thenReturn("HotelBookingID1");
+    when(activities.reserveCar("trip1")).thenReturn("CarBookingID1");
+    when(activities.bookFlight("trip1"))
+        .thenThrow(new RuntimeException("Flight booking did not work"));
+    worker.registerActivitiesImplementations(activities);
+
+    testEnv.start();
+
+    TripBookingWorkflow workflow = workflowClient.newWorkflowStub(TripBookingWorkflow.class);
+    try {
+      workflow.bookTrip("trip1");
+      fail("unreachable");
+    } catch (WorkflowException e) {
+      assertEquals("Flight booking did not work", e.getCause().getCause().getMessage());
+    }
+
+    verify(activities).cancelHotel(eq("HotelBookingID1"), eq("trip1"));
+    verify(activities).cancelCar(eq("CarBookingID1"), eq("trip1"));
+  }
+}