Added in-memory Cadence service implementation to support unit testing. (#125)

Author: mfateev

src/main/java/com/uber/cadence/activity/ActivityOptions.java

@@ -73,6 +73,9 @@ public Builder() {}
 
     /** Copy Builder fields from the options. */
     public Builder(ActivityOptions options) {
+      if (options == null) {
+        return;
+      }
       this.scheduleToStartTimeout = options.getScheduleToStartTimeout();
       this.scheduleToCloseTimeout = options.getScheduleToCloseTimeout();
       this.heartbeatTimeout = options.getHeartbeatTimeout();

src/main/java/com/uber/cadence/client/WorkflowClient.java

@@ -21,7 +21,6 @@
 import com.uber.cadence.activity.Activity;
 import com.uber.cadence.internal.sync.WorkflowClientInternal;
 import com.uber.cadence.serviceclient.IWorkflowService;
-import com.uber.cadence.serviceclient.WorkflowServiceTChannel;
 import com.uber.cadence.workflow.Functions;
 import com.uber.cadence.workflow.Functions.Func;
 import com.uber.cadence.workflow.Functions.Func1;
@@ -81,8 +80,7 @@ public interface WorkflowClient {
    * @param domain domain that worker uses to poll.
    */
   static WorkflowClient newInstance(String domain) {
-    return new WorkflowClientInternal(
-        new WorkflowServiceTChannel(), domain, new WorkflowClientOptions.Builder().build());
+    return WorkflowClientInternal.newInstance(domain);
   }
 
   /**
@@ -94,7 +92,7 @@ static WorkflowClient newInstance(String domain) {
    *     configuring client.
    */
   static WorkflowClient newInstance(String domain, WorkflowClientOptions options) {
-    return new WorkflowClientInternal(new WorkflowServiceTChannel(), domain, options);
+    return WorkflowClientInternal.newInstance(domain, options);
   }
 
   /**
@@ -105,10 +103,7 @@ static WorkflowClient newInstance(String domain, WorkflowClientOptions options)
    * @param domain domain that worker uses to poll.
    */
   static WorkflowClient newInstance(String host, int port, String domain) {
-    return new WorkflowClientInternal(
-        new WorkflowServiceTChannel(host, port),
-        domain,
-        new WorkflowClientOptions.Builder().build());
+    return WorkflowClientInternal.newInstance(host, port, domain);
   }
 
   /**
@@ -122,7 +117,7 @@ static WorkflowClient newInstance(String host, int port, String domain) {
    */
   static WorkflowClient newInstance(
       String host, int port, String domain, WorkflowClientOptions options) {
-    return new WorkflowClientInternal(new WorkflowServiceTChannel(host, port), domain, options);
+    return WorkflowClientInternal.newInstance(host, port, domain, options);
   }
 
   /**
@@ -132,7 +127,7 @@ static WorkflowClient newInstance(
    * @param domain domain that worker uses to poll.
    */
   static WorkflowClient newInstance(IWorkflowService service, String domain) {
-    return new WorkflowClientInternal(service, domain, null);
+    return WorkflowClientInternal.newInstance(service, domain);
   }
 
   /**
@@ -145,9 +140,11 @@ static WorkflowClient newInstance(IWorkflowService service, String domain) {
    */
   static WorkflowClient newInstance(
       IWorkflowService service, String domain, WorkflowClientOptions options) {
-    return new WorkflowClientInternal(service, domain, options);
+    return WorkflowClientInternal.newInstance(service, domain, options);
   }
 
+  String getDomain();
+
   /**
    * Creates workflow client stub that can be used to start a single workflow execution. The first
    * call must be to a method annotated with @WorkflowMethod. After workflow is started it can be

src/main/java/com/uber/cadence/client/WorkflowNotFoundException.java

@@ -0,0 +1,32 @@
+/*
+ *  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.client;
+
+import com.uber.cadence.WorkflowExecution;
+
+/**
+ * Thrown when workflow with the given id is not known to the cadence service. It could be because
+ * id is not correct or workflow was purged from the service after reaching its retention limit.
+ */
+public final class WorkflowNotFoundException extends WorkflowException {
+
+  public WorkflowNotFoundException(
+      WorkflowExecution execution, String workflowType, String message) {
+    super(message, execution, workflowType, null);
+  }
+}

src/main/java/com/uber/cadence/client/WorkflowQueryException.java

@@ -0,0 +1,27 @@
+/*
+ *  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.client;
+
+import com.uber.cadence.WorkflowExecution;
+
+public final class WorkflowQueryException extends WorkflowException {
+
+  public WorkflowQueryException(WorkflowExecution execution, String message) {
+    super(message, execution, null, null);
+  }
+}

src/main/java/com/uber/cadence/client/WorkflowServiceException.java

@@ -0,0 +1,27 @@
+/*
+ *  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.client;
+
+import com.uber.cadence.WorkflowExecution;
+
+public final class WorkflowServiceException extends WorkflowException {
+
+  public WorkflowServiceException(WorkflowExecution execution, String message) {
+    super(message, execution, null, null);
+  }
+}

src/main/java/com/uber/cadence/converter/JsonDataConverter.java

@@ -81,7 +81,7 @@ public static DataConverter getInstance() {
     return INSTANCE;
   }
 
-  public JsonDataConverter() {
+  private JsonDataConverter() {
     this((b) -> b);
   }
 

src/main/java/com/uber/cadence/internal/common/LambdaUtils.java

@@ -0,0 +1,71 @@
+/*
+ *  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.internal.common;
+
+import com.uber.cadence.workflow.Functions;
+import java.lang.invoke.SerializedLambda;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+
+public final class LambdaUtils {
+
+  /**
+   * Get target of the method reference that was converted to a lambda.
+   *
+   * @param l lambda expression that could be a method reference.
+   * @return either target of the method reference or null if it is not reference in form
+   *     object::method.
+   */
+  public static Object getTarget(SerializedLambda l) {
+    if (l == null) {
+      return null;
+    }
+    // If lambda is a method call on an object then the first captured argument is the object.
+    if (l.getCapturedArgCount() > 0) {
+      return l.getCapturedArg(0);
+    }
+    return null;
+  }
+
+  /**
+   * Unfortunate sorcery to reflect on lambda. Works only if function that lambda implements is
+   * serializable. This is why {@link Functions} is needed as all its functions are serializable.
+   *
+   * @param lambda lambda that potentially implements {@link java.io.Serializable}.
+   * @return lambda in {@link SerializedLambda} form or null if its function doesn't implement
+   *     Serializable.
+   */
+  public static SerializedLambda toSerializedLambda(Object lambda) {
+    for (Class<?> cl = lambda.getClass(); cl != null; cl = cl.getSuperclass()) {
+      try {
+        Method m = cl.getDeclaredMethod("writeReplace");
+        m.setAccessible(true);
+        Object replacement = m.invoke(lambda);
+        if (!(replacement instanceof SerializedLambda)) break; // custom interface implementation
+        return (SerializedLambda) replacement;
+      } catch (NoSuchMethodException e) {
+      } catch (IllegalAccessException | InvocationTargetException e) {
+        break;
+      }
+    }
+    return null;
+  }
+
+  /** Prohibits instantiation. */
+  private LambdaUtils() {}
+}

src/main/java/com/uber/cadence/internal/common/Retryer.java

@@ -214,7 +214,7 @@ private static <R> ValueExceptionPair<R> failOrRetry(
     }
     int maxAttempts = options.getMaximumAttempts();
     if ((maxAttempts > 0 && attempt >= maxAttempts)
-        || (elapsed >= options.getExpiration().toMillis()
+        || ((options.getExpiration() != null && elapsed >= options.getExpiration().toMillis())
             && attempt >= options.getMinimumAttempts())) {
       return new ValueExceptionPair<>(null, e);
     }