More updates to address PR comments

* Making template constants private
* Adding helper methods to extract variables from template paths
* Making it possible to have multiple instances of LocalPubsubHelper
* Removing getChannel from *Api classes (not used anywhere)
* Other cleanup

gcloud-java-pubsub/src/main/java/com/google/gcloud/pubsub/spi/PublisherApi.java

@@ -49,7 +49,6 @@
 import io.gapi.gax.grpc.ServiceApiSettings;
 import io.gapi.gax.internal.ApiUtils;
 import io.gapi.gax.protobuf.PathTemplate;
-import io.grpc.Channel;
 import io.grpc.ManagedChannel;
 
 import java.io.IOException;
@@ -151,14 +150,14 @@ public Iterable<String> extractResources(ListTopicSubscriptionsResponse payload)
    * A PathTemplate representing the fully-qualified path to represent
    * a project resource.
    */
-  public static final PathTemplate PROJECT_PATH_TEMPLATE =
+  private static final PathTemplate PROJECT_PATH_TEMPLATE =
       PathTemplate.create("/projects/{project}");
 
   /**
    * A PathTemplate representing the fully-qualified path to represent
    * a topic resource.
    */
-  public static final PathTemplate TOPIC_PATH_TEMPLATE =
+  private static final PathTemplate TOPIC_PATH_TEMPLATE =
       PathTemplate.create("/projects/{project}/topics/{topic}");
 
   // ========
@@ -220,13 +219,28 @@ public static final String createTopicPath(String project, String topic) {
         "project", project,"topic", topic);
   }
 
+  /**
+   * Extracts the project from the given fully-qualified path which
+   * represents a project resource.
+   */
+  public static final String extractProjectFromProjectPath(String projectPath) {
+    return PROJECT_PATH_TEMPLATE.parse(projectPath).get("project");
+  }
 
-  // ========
-  // Getters
-  // ========
+  /**
+   * Extracts the project from the given fully-qualified path which
+   * represents a topic resource.
+   */
+  public static final String extractProjectFromTopicPath(String topicPath) {
+    return TOPIC_PATH_TEMPLATE.parse(topicPath).get("project");
+  }
 
-  public Channel getChannel() {
-    return channel;
+  /**
+   * Extracts the topic from the given fully-qualified path which
+   * represents a topic resource.
+   */
+  public static final String extractTopicFromTopicPath(String topicPath) {
+    return TOPIC_PATH_TEMPLATE.parse(topicPath).get("topic");
   }
 
 

gcloud-java-pubsub/src/main/java/com/google/gcloud/pubsub/spi/SubscriberApi.java

@@ -50,7 +50,6 @@
 import io.gapi.gax.grpc.ServiceApiSettings;
 import io.gapi.gax.internal.ApiUtils;
 import io.gapi.gax.protobuf.PathTemplate;
-import io.grpc.Channel;
 import io.grpc.ManagedChannel;
 
 import java.io.IOException;
@@ -132,14 +131,14 @@ public Iterable<Subscription> extractResources(ListSubscriptionsResponse payload
    * A PathTemplate representing the fully-qualified path to represent
    * a project resource.
    */
-  public static final PathTemplate PROJECT_PATH_TEMPLATE =
+  private static final PathTemplate PROJECT_PATH_TEMPLATE =
       PathTemplate.create("/projects/{project}");
 
   /**
    * A PathTemplate representing the fully-qualified path to represent
    * a subscription resource.
    */
-  public static final PathTemplate SUBSCRIPTION_PATH_TEMPLATE =
+  private static final PathTemplate SUBSCRIPTION_PATH_TEMPLATE =
       PathTemplate.create("/projects/{project}/subscriptions/{subscription}");
 
   // ========
@@ -168,7 +167,11 @@ public static SubscriberApi create(ServiceApiSettings settings) throws IOExcepti
     return new SubscriberApi(settings);
   }
 
-  private SubscriberApi(ServiceApiSettings settings) throws IOException {
+  /**
+   * Constructs an instance of SubscriberApi, using the given settings. This is protected so that it
+   * easy to make a subclass, but otherwise, the static factory methods should be preferred.
+   */
+  protected SubscriberApi(ServiceApiSettings settings) throws IOException {
     ServiceApiSettings internalSettings = ApiUtils.settingsWithChannels(settings,
         SERVICE_ADDRESS, DEFAULT_SERVICE_PORT, ALL_SCOPES);
     this.settings = internalSettings;
@@ -197,13 +200,28 @@ public static final String createSubscriptionPath(String project, String subscri
         "project", project,"subscription", subscription);
   }
 
+  /**
+   * Extracts the project from the given fully-qualified path which
+   * represents a project resource.
+   */
+  public static final String extractProjectFromProjectPath(String projectPath) {
+    return PROJECT_PATH_TEMPLATE.parse(projectPath).get("project");
+  }
 
-  // ========
-  // Getters
-  // ========
+  /**
+   * Extracts the project from the given fully-qualified path which
+   * represents a subscription resource.
+   */
+  public static final String extractProjectFromSubscriptionPath(String subscriptionPath) {
+    return SUBSCRIPTION_PATH_TEMPLATE.parse(subscriptionPath).get("project");
+  }
 
-  public Channel getChannel() {
-    return channel;
+  /**
+   * Extracts the subscription from the given fully-qualified path which
+   * represents a subscription resource.
+   */
+  public static final String extractSubscriptionFromSubscriptionPath(String subscriptionPath) {
+    return SUBSCRIPTION_PATH_TEMPLATE.parse(subscriptionPath).get("subscription");
   }
 
 

gcloud-java-pubsub/src/main/java/com/google/gcloud/pubsub/spi/testing/LocalPublisherImpl.java

@@ -77,8 +77,8 @@ public void getTopic(GetTopicRequest request, StreamObserver<Topic> responseObse
   public void listTopics(ListTopicsRequest request, StreamObserver<ListTopicsResponse> responseObserver) {
     List<Topic> responseTopics = new ArrayList<>();
     for (String topicName : topics.keySet()) {
-      String projectOfTopic = PublisherApi.TOPIC_PATH_TEMPLATE.parse(topicName).get("project");
-      String projectOfRequest = PublisherApi.PROJECT_PATH_TEMPLATE.parse(request.getProject()).get("project");
+      String projectOfTopic = PublisherApi.extractProjectFromTopicPath(topicName);
+      String projectOfRequest = PublisherApi.extractProjectFromProjectPath(request.getProject());
       if (projectOfTopic.equals(projectOfRequest)) {
         Topic topicObj = Topic.newBuilder().setName(topicName).build();
         responseTopics.add(topicObj);

gcloud-java-pubsub/src/main/java/com/google/gcloud/pubsub/testing/LocalPubsubHelper.java

@@ -19,19 +19,22 @@
  * A class that runs an in-memory Publisher instance for use in tests.
  */
 public class LocalPubsubHelper {
-  private static final SocketAddress address = new LocalAddress("in-process-1");
-  private static Server server;
-  private static LocalPublisherImpl publisherImpl;
+  private static int FLOW_CONTROL_WINDOW = 65 * 1024;
+
+  private final SocketAddress address;
+  private final Server server;
+  private final LocalPublisherImpl publisherImpl;
 
   /**
    * Constructs a new LocalPubsubHelper. The method start() must
    * be called before it is used.
    */
-  public LocalPubsubHelper() {
+  public LocalPubsubHelper(String addressString) {
+    address = new LocalAddress(addressString);
     publisherImpl = new LocalPublisherImpl();
     NettyServerBuilder builder = NettyServerBuilder
         .forAddress(address)
-        .flowControlWindow(65 * 1024)
+        .flowControlWindow(FLOW_CONTROL_WINDOW)
         .channelType(LocalServerChannel.class);
     builder.addService(PublisherGrpc.bindService(publisherImpl));
     server = builder.build();

gcloud-java-pubsub/src/test/java/com/google/gcloud/pubsub/spi/PublisherApiTest.java

@@ -38,7 +38,7 @@ public class PublisherApiTest {
 
   @BeforeClass
   public static void startStaticServer() {
-    pubsubHelper = new LocalPubsubHelper().start();
+    pubsubHelper = new LocalPubsubHelper("in-process-1").start();
   }
 
   @AfterClass