pubsub: update README to use high perf clients

google-cloud-examples/src/main/java/com/google/cloud/examples/pubsub/snippets/CreateSubscriptionAndPullMessages.java

@@ -56,6 +56,7 @@ public void receiveMessage(PubsubMessage message, AckReplyConsumer consumer) {
           new Subscriber.SubscriberListener() {
             @Override
             public void failed(Subscriber.State from, Throwable failure) {
+              // Handle failure. This is called when the Subscriber encountered a fatal error and is shutting down.
               System.err.println(failure);
             }
           },

google-cloud-pubsub/README.md

@@ -85,17 +85,7 @@ To make authenticated requests to Google Cloud Pub/Sub, you must create a servic
 credentials. You can then make API calls by calling methods on the Pub/Sub service object. The
 simplest way to authenticate is to use
 [Application Default Credentials](https://developers.google.com/identity/protocols/application-default-credentials).
-These credentials are automatically inferred from your environment, so you only need the following
-code to create your service object:
-
-```java
-import com.google.cloud.pubsub.PubSub;
-import com.google.cloud.pubsub.PubSubOptions;
-
-try(PubSub pubsub = PubSubOptions.getDefaultInstance().getService()) {
-  // use pubsub here
-}
-```
+These credentials are automatically inferred from your environment.
 
 For other authentication options, see the
 [Authentication](https://github.com/GoogleCloudPlatform/google-cloud-java#authentication) page.
@@ -105,65 +95,108 @@ With Pub/Sub you can create topics. A topic is a named resource to which message
 publishers. Add the following imports at the top of your file:
 
 ```java
-import com.google.cloud.pubsub.Topic;
-import com.google.cloud.pubsub.TopicInfo;
+import com.google.cloud.pubsub.spi.v1.PublisherClient;
+import com.google.pubsub.v1.TopicName;
 ```
 Then, to create the topic, use the following code:
 
 ```java
-Topic topic = pubsub.create(TopicInfo.of("test-topic"));
+TopicName topic = TopicName.create("test-project", "test-topic");
+try (PublisherClient publisherClient = PublisherClient.create()) {
+  publisherClient.createTopic(topic);
+}
 ```
 
 #### Publishing messages
 With Pub/Sub you can publish messages to a topic. Add the following import at the top of your file:
 
 ```java
-import com.google.cloud.pubsub.Message;
+import com.google.api.gax.core.RpcFuture;
+import com.google.cloud.pubsub.spi.v1.Publisher;
+import com.google.protobuf.ByteString;
+import com.google.pubsub.v1.PubsubMessage;
 ```
 Then, to publish messages asynchronously, use the following code:
 
 ```java
-Message message1 = Message.of("First message");
-Message message2 = Message.of("Second message");
-topic.publishAsync(message1, message2);
+Publisher publisher = null;
+try {
+  publisher = Publisher.newBuilder(topic).build();
+  ByteString data = ByteString.copyFromUtf8("my-message");
+  PubsubMessage pubsubMessage = PubsubMessage.newBuilder().setData(data).build();
+  RpcFuture<String> messageIdFuture = publisher.publish(pubsubMessage);
+} finally {
+  if (publisher != null) {
+    publisher.shutdown();
+  }
+}
 ```
 
 #### Creating a subscription
 With Pub/Sub you can create subscriptions. A subscription represents the stream of messages from a
 single, specific topic. Add the following imports at the top of your file:
 
 ```java
-import com.google.cloud.pubsub.Subscription;
-import com.google.cloud.pubsub.SubscriptionInfo;
+import com.google.cloud.pubsub.spi.v1.SubscriberClient;
+import com.google.pubsub.v1.PushConfig;
+import com.google.pubsub.v1.SubscriptionName;
+import com.google.pubsub.v1.TopicName;
 ```
 Then, to create the subscription, use the following code:
 
 ```java
-Subscription subscription =
-    pubsub.create(SubscriptionInfo.of("test-topic", "test-subscription"));
+TopicName topic = TopicName.create("test-project", "test-topic");
+SubscriptionName subscription = SubscriptionName.create("test-project", "test-subscription");
+
+try (SubscriberClient subscriberClient = SubscriberClient.create()) {
+  subscriberClient.createSubscription(subscription, topic, PushConfig.getDefaultInstance(), 0);
+}
 ```
 
 #### Pulling messages
 With Pub/Sub you can pull messages from a subscription. Add the following imports at the top of your
 file:
 
 ```java
-import com.google.cloud.pubsub.Message;
-import com.google.cloud.pubsub.PubSub.MessageConsumer;
-import com.google.cloud.pubsub.PubSub.MessageProcessor;
+import com.google.cloud.pubsub.spi.v1.AckReply;
+import com.google.cloud.pubsub.spi.v1.AckReplyConsumer;
+import com.google.cloud.pubsub.spi.v1.MessageReceiver;
+import com.google.cloud.pubsub.spi.v1.Subscriber;
+import com.google.common.util.concurrent.MoreExecutors;
+import com.google.pubsub.v1.PubsubMessage;
+import com.google.pubsub.v1.SubscriptionName;
+import com.google.pubsub.v1.TopicName;
 ```
 Then, to pull messages asynchronously, use the following code:
 
 ```java
-MessageProcessor callback = new MessageProcessor() {
-  @Override
-  public void process(Message message) throws Exception {
-    System.out.printf("Received message \"%s\"%n", message.getPayloadAsString());
+MessageReceiver receiver =
+    new MessageReceiver() {
+      @Override
+      public void receiveMessage(PubsubMessage message, AckReplyConsumer consumer) {
+        System.out.println("got message: " + message.getData().toStringUtf8());
+        consumer.accept(AckReply.ACK, null);
+      }
+    };
+Subscriber subscriber = null;
+try {
+  subscriber = Subscriber.newBuilder(subscription, receiver).build();
+  subscriber.addListener(
+      new Subscriber.SubscriberListener() {
+        @Override
+        public void failed(Subscriber.State from, Throwable failure) {
+          // Handle failure. This is called when the Subscriber encountered a fatal error and is shutting down.
+          System.err.println(failure);
+        }
+      },
+      MoreExecutors.directExecutor());
+  subscriber.startAsync().awaitRunning();
+  // Pull messages for 60 seconds.
+  Thread.sleep(60000);
+} finally {
+  if (subscriber != null) {
+    subscriber.stopAsync();
   }
-};
-// Create a message consumer and pull messages (for 60 seconds)
-try (MessageConsumer consumer = subscription.pullAsync(callback)) {
-  Thread.sleep(60_000);
 }
 ```
 #### Complete source code