Add Nexus cancellation sample (#718)

* Update Nexus Sample for v1.28.0

* fix typo

* Small updates

* Add Nexus Cancellation Sample

* Update cancellation sample

* fix typo

* run license check

* add log

* run spotless

Author: Quinn-With-Two-Ns

core/src/main/java/io/temporal/samples/nexuscancellation/README.MD

@@ -0,0 +1,36 @@
+# Nexus Cancellation
+
+This sample shows how to cancel a Nexus operation from a caller workflow.
+
+From more details on Nexus and how to setup to run this samples please see the [Nexus Sample](../nexus/README.MD).
+
+In separate terminal windows:
+
+### Nexus handler worker
+
+```
+./gradlew -q execute -PmainClass=io.temporal.samples.nexuscancellation.handler.HandlerWorker \
+    --args="-target-host localhost:7233 -namespace my-target-namespace"
+```
+
+### Nexus caller worker
+
+```
+./gradlew -q execute -PmainClass=io.temporal.samples.nexuscancellation.caller.CallerWorker \
+    --args="-target-host localhost:7233 -namespace my-caller-namespace"
+```
+
+### Start caller workflow
+
+```
+./gradlew -q execute -PmainClass=io.temporal.samples.nexuscancellation.caller.CallerStarter \
+    --args="-target-host localhost:7233 -namespace my-caller-namespace"
+```
+
+### Output
+
+which should result in:
+```
+INFO  i.t.s.n.caller.CallerStarter - Started workflow workflowId: 326732dd-a2b1-4de7-9ddd-dcee4f9f0229 runId: d580499f-79d5-461d-bd49-6248b4e522ae 
+INFO  i.t.s.n.caller.CallerStarter - Workflow result: Hallo Nexus 👋 
+```

core/src/main/java/io/temporal/samples/nexuscancellation/caller/CallerStarter.java

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+/*
+ *  Copyright (c) 2020 Temporal Technologies, Inc. All Rights Reserved
+ *
+ *  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 io.temporal.samples.nexuscancellation.caller;
+
+import io.temporal.api.common.v1.WorkflowExecution;
+import io.temporal.client.WorkflowClient;
+import io.temporal.client.WorkflowOptions;
+import io.temporal.samples.nexus.options.ClientOptions;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class CallerStarter {
+  private static final Logger logger = LoggerFactory.getLogger(CallerStarter.class);
+
+  public static void main(String[] args) {
+    WorkflowClient client = ClientOptions.getWorkflowClient(args);
+
+    WorkflowOptions workflowOptions =
+        WorkflowOptions.newBuilder().setTaskQueue(CallerWorker.DEFAULT_TASK_QUEUE_NAME).build();
+    HelloCallerWorkflow helloWorkflow =
+        client.newWorkflowStub(HelloCallerWorkflow.class, workflowOptions);
+    WorkflowExecution execution = WorkflowClient.start(helloWorkflow::hello, "Nexus");
+    logger.info(
+        "Started workflow workflowId: {} runId: {}",
+        execution.getWorkflowId(),
+        execution.getRunId());
+    logger.info("Workflow result: {}", helloWorkflow.hello("Nexus"));
+  }
+}

core/src/main/java/io/temporal/samples/nexuscancellation/caller/CallerWorker.java

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+/*
+ *  Copyright (c) 2020 Temporal Technologies, Inc. All Rights Reserved
+ *
+ *  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 io.temporal.samples.nexuscancellation.caller;
+
+import io.temporal.client.WorkflowClient;
+import io.temporal.samples.nexus.options.ClientOptions;
+import io.temporal.samples.nexus.service.NexusService;
+import io.temporal.worker.Worker;
+import io.temporal.worker.WorkerFactory;
+import io.temporal.worker.WorkflowImplementationOptions;
+import io.temporal.workflow.NexusServiceOptions;
+import java.util.Collections;
+
+public class CallerWorker {
+  public static final String DEFAULT_TASK_QUEUE_NAME = "my-caller-workflow-task-queue";
+
+  public static void main(String[] args) {
+    WorkflowClient client = ClientOptions.getWorkflowClient(args);
+
+    WorkerFactory factory = WorkerFactory.newInstance(client);
+
+    Worker worker = factory.newWorker(DEFAULT_TASK_QUEUE_NAME);
+    worker.registerWorkflowImplementationTypes(
+        WorkflowImplementationOptions.newBuilder()
+            .setNexusServiceOptions(
+                Collections.singletonMap(
+                    NexusService.class.getSimpleName(),
+                    NexusServiceOptions.newBuilder().setEndpoint("my-nexus-endpoint-name").build()))
+            .build(),
+        HelloCallerWorkflowImpl.class);
+
+    factory.start();
+  }
+}

core/src/main/java/io/temporal/samples/nexuscancellation/caller/HelloCallerWorkflow.java

@@ -0,0 +1,29 @@
+/*
+ *  Copyright (c) 2020 Temporal Technologies, Inc. All Rights Reserved
+ *
+ *  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 io.temporal.samples.nexuscancellation.caller;
+
+import io.temporal.workflow.WorkflowInterface;
+import io.temporal.workflow.WorkflowMethod;
+
+@WorkflowInterface
+public interface HelloCallerWorkflow {
+  @WorkflowMethod
+  String hello(String message);
+}

core/src/main/java/io/temporal/samples/nexuscancellation/caller/HelloCallerWorkflowImpl.java

@@ -0,0 +1,95 @@
+/*
+ *  Copyright (c) 2020 Temporal Technologies, Inc. All Rights Reserved
+ *
+ *  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 io.temporal.samples.nexuscancellation.caller;
+
+import static io.temporal.samples.nexus.service.NexusService.Language.*;
+
+import io.temporal.failure.CanceledFailure;
+import io.temporal.failure.NexusOperationFailure;
+import io.temporal.samples.nexus.service.NexusService;
+import io.temporal.workflow.*;
+import java.time.Duration;
+import java.util.ArrayList;
+import java.util.List;
+import org.slf4j.Logger;
+
+public class HelloCallerWorkflowImpl implements HelloCallerWorkflow {
+  public static final Logger log = Workflow.getLogger(HelloCallerWorkflowImpl.class);
+  private static final NexusService.Language[] languages =
+      new NexusService.Language[] {EN, FR, DE, ES, TR};
+  NexusService nexusService =
+      Workflow.newNexusServiceStub(
+          NexusService.class,
+          NexusServiceOptions.newBuilder()
+              .setOperationOptions(
+                  NexusOperationOptions.newBuilder()
+                      .setScheduleToCloseTimeout(Duration.ofSeconds(10))
+                      .build())
+              .build());
+
+  @Override
+  public String hello(String message) {
+    List<Promise<NexusService.HelloOutput>> results = new ArrayList<>(languages.length);
+
+    /*
+     * Create our CancellationScope. Within this scope we call the nexus operation asynchronously
+     * hello method asynchronously for each of our defined languages.
+     */
+    CancellationScope scope =
+        Workflow.newCancellationScope(
+            () -> {
+              for (NexusService.Language language : languages) {
+                results.add(
+                    Async.function(
+                        nexusService::hello, new NexusService.HelloInput(message, language)));
+              }
+            });
+
+    /*
+     * Execute all nexus operations within the CancellationScope. Note that this execution is
+     * non-blocking as the code inside our cancellation scope is also non-blocking.
+     */
+    scope.run();
+
+    // We use "anyOf" here to wait for one of the nexus operation invocations to return
+    NexusService.HelloOutput result = Promise.anyOf(results).get();
+
+    // Trigger cancellation of all uncompleted nexus operations invocations within the cancellation
+    // scope
+    scope.cancel();
+    // Optionally, wait for all nexus operations to complete
+    //
+    // Note: Once the workflow completes any pending cancellation requests are dropped by the
+    // server.
+    for (Promise<NexusService.HelloOutput> promise : results) {
+      try {
+        promise.get();
+      } catch (NexusOperationFailure e) {
+        // If the operation was cancelled, we can ignore the failure
+        if (e.getCause() instanceof CanceledFailure) {
+          log.info("Operation was cancelled");
+          continue;
+        }
+        throw e;
+      }
+    }
+    return result.getMessage();
+  }
+}

core/src/main/java/io/temporal/samples/nexuscancellation/handler/HandlerWorker.java

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+/*
+ *  Copyright (c) 2020 Temporal Technologies, Inc. All Rights Reserved
+ *
+ *  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 io.temporal.samples.nexuscancellation.handler;
+
+import io.temporal.client.WorkflowClient;
+import io.temporal.samples.nexus.handler.NexusServiceImpl;
+import io.temporal.samples.nexus.options.ClientOptions;
+import io.temporal.worker.Worker;
+import io.temporal.worker.WorkerFactory;
+
+public class HandlerWorker {
+  public static final String DEFAULT_TASK_QUEUE_NAME = "my-handler-task-queue";
+
+  public static void main(String[] args) {
+    WorkflowClient client = ClientOptions.getWorkflowClient(args);
+
+    WorkerFactory factory = WorkerFactory.newInstance(client);
+
+    Worker worker = factory.newWorker(DEFAULT_TASK_QUEUE_NAME);
+    worker.registerWorkflowImplementationTypes(HelloHandlerWorkflowImpl.class);
+    worker.registerNexusServiceImplementation(new NexusServiceImpl());
+
+    factory.start();
+  }
+}

core/src/main/java/io/temporal/samples/nexuscancellation/handler/HelloHandlerWorkflowImpl.java

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+/*
+ *  Copyright (c) 2020 Temporal Technologies, Inc. All Rights Reserved
+ *
+ *  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 io.temporal.samples.nexuscancellation.handler;
+
+import io.temporal.failure.ApplicationFailure;
+import io.temporal.samples.nexus.handler.HelloHandlerWorkflow;
+import io.temporal.samples.nexus.service.NexusService;
+import io.temporal.workflow.Workflow;
+import java.time.Duration;
+
+public class HelloHandlerWorkflowImpl implements HelloHandlerWorkflow {
+  @Override
+  public NexusService.HelloOutput hello(NexusService.HelloInput input) {
+    // Sleep for a random duration to simulate some work
+    Workflow.sleep(Duration.ofSeconds(Workflow.newRandom().nextInt(5)));
+    switch (input.getLanguage()) {
+      case EN:
+        return new NexusService.HelloOutput("Hello " + input.getName() + " 👋");
+      case FR:
+        return new NexusService.HelloOutput("Bonjour " + input.getName() + " 👋");
+      case DE:
+        return new NexusService.HelloOutput("Hallo " + input.getName() + " 👋");
+      case ES:
+        return new NexusService.HelloOutput("¡Hola! " + input.getName() + " 👋");
+      case TR:
+        return new NexusService.HelloOutput("Merhaba " + input.getName() + " 👋");
+    }
+    throw ApplicationFailure.newFailure(
+        "Unsupported language: " + input.getLanguage(), "UNSUPPORTED_LANGUAGE");
+  }
+}