Merge pull request #69 from uber/signal-sample

Add signal samples in Java

Author: chopincode

src/main/java/com/uber/cadence/samples/spring/cadence/CadenceAutoConfiguration.java

@@ -5,7 +5,8 @@
 
 import com.uber.cadence.client.WorkflowClient;
 import com.uber.cadence.client.WorkflowClientOptions;
-import com.uber.cadence.samples.spring.workflows.HelloWorldWorkflowImpl;
+import com.uber.cadence.samples.spring.workflows.impl.HelloWorldWorkflowImpl;
+import com.uber.cadence.samples.spring.workflows.impl.SignalWorkflowImpl;
 import com.uber.cadence.serviceclient.ClientOptions;
 import com.uber.cadence.serviceclient.WorkflowServiceTChannel;
 import com.uber.cadence.worker.Worker;
@@ -33,7 +34,12 @@ public void startWorker(ApplicationStartedEvent event) {
     WorkflowClient workflowClient = context.getBean(WorkflowClient.class);
     WorkerFactory factory = WorkerFactory.newInstance(workflowClient);
     Worker worker = factory.newWorker(TASK_LIST);
+
+    // HelloWorldWorkflow registration
     worker.registerWorkflowImplementationTypes(HelloWorldWorkflowImpl.class);
+
+    // SignalWorkflow registration
+    worker.registerWorkflowImplementationTypes(SignalWorkflowImpl.class);
     factory.start();
   }
 }

src/main/java/com/uber/cadence/samples/spring/workflows/SignalWorkflow.java

@@ -0,0 +1,16 @@
+package com.uber.cadence.samples.spring.workflows;
+
+import com.uber.cadence.samples.spring.models.SampleMessage;
+import com.uber.cadence.workflow.SignalMethod;
+import com.uber.cadence.workflow.WorkflowMethod;
+
+public interface SignalWorkflow {
+  @WorkflowMethod
+  void getGreeting(SampleMessage sampleMessage);
+
+  @SignalMethod
+  void waitForGreeting(String greeting);
+
+  @SignalMethod
+  void cancel();
+}

src/main/java/com/uber/cadence/samples/spring/workflows/HelloWorldWorkflowImpl.java renamed to src/main/java/com/uber/cadence/samples/spring/workflows/impl/HelloWorldWorkflowImpl.java

@@ -1,6 +1,7 @@
-package com.uber.cadence.samples.spring.workflows;
+package com.uber.cadence.samples.spring.workflows.impl;
 
 import com.uber.cadence.samples.spring.models.SampleMessage;
+import com.uber.cadence.samples.spring.workflows.HelloWorldWorkflow;
 import com.uber.cadence.workflow.Workflow;
 import org.slf4j.Logger;
 

src/main/java/com/uber/cadence/samples/spring/workflows/impl/SignalWorkflowImpl.java

@@ -0,0 +1,46 @@
+package com.uber.cadence.samples.spring.workflows.impl;
+
+import com.uber.cadence.samples.spring.models.SampleMessage;
+import com.uber.cadence.samples.spring.workflows.SignalWorkflow;
+import com.uber.cadence.workflow.Workflow;
+import org.slf4j.Logger;
+
+public class SignalWorkflowImpl implements SignalWorkflow {
+  private final Logger logger = Workflow.getLogger(SignalWorkflowImpl.class);
+  private String name;
+  private String greetingMsg = "";
+  private boolean cancel = false;
+
+  @Override
+  public void getGreeting(SampleMessage sampleMessage) {
+    logger.info("executing SignalWorkflow::getGreeting");
+    this.name = sampleMessage.GetMessage();
+    int count = 0;
+
+    while (!cancel) {
+      Workflow.await(() -> cancel || !this.greetingMsg.isEmpty());
+      if (!this.greetingMsg.isEmpty()) {
+        logger.info(++count + ": " + this.greetingMsg + "!");
+        this.greetingMsg = "";
+      }
+    }
+
+    logger.info("workflow canceled");
+  }
+
+  @Override
+  public void waitForGreeting(String greeting) {
+    if (cancel) {
+      logger.info("signal workflow failed because it is already cancelled");
+      return;
+    }
+
+    logger.info("received signal from SignalWorkflow:waitForName");
+    this.greetingMsg = String.format("%s, %s!", greeting, this.name);
+  }
+
+  @Override
+  public void cancel() {
+    this.cancel = true;
+  }
+}