Add javadoc and unit tests for SubscriptionInfo (#977)

Author: mziccard

gcloud-java-pubsub/src/main/java/com/google/cloud/pubsub/Subscription.java

@@ -21,6 +21,7 @@
 import com.google.cloud.pubsub.PubSub.MessageConsumer;
 import com.google.cloud.pubsub.PubSub.MessageProcessor;
 import com.google.cloud.pubsub.PubSub.PullOption;
+import com.google.common.base.Function;
 
 import java.io.IOException;
 import java.io.ObjectInputStream;
@@ -103,7 +104,11 @@ public boolean equals(Object obj) {
       return false;
     }
     Subscription other = (Subscription) obj;
-    return Objects.equals(toPb(), other.toPb()) && Objects.equals(options, other.options);
+    return Objects.equals(topic(), other.topic())
+        && Objects.equals(name(), other.name())
+        && Objects.equals(pushConfig(), other.pushConfig())
+        && ackDeadlineSeconds() == other.ackDeadlineSeconds()
+        && Objects.equals(options, other.options);
   }
 
   public PubSub pubSub() {
@@ -155,4 +160,14 @@ static Subscription fromPb(PubSub storage, com.google.pubsub.v1.Subscription sub
     SubscriptionInfo subscriptionInfo = SubscriptionInfo.fromPb(subscriptionPb);
     return new Subscription(storage, new BuilderImpl(subscriptionInfo));
   }
+
+  static Function<com.google.pubsub.v1.Subscription, Subscription> fromPbFunction(
+      final PubSub pubsub) {
+    return new Function<com.google.pubsub.v1.Subscription, Subscription>() {
+      @Override
+      public Subscription apply(com.google.pubsub.v1.Subscription subscriptionPb) {
+        return fromPb(pubsub, subscriptionPb);
+      }
+    };
+  }
 }

gcloud-java-pubsub/src/main/java/com/google/cloud/pubsub/SubscriptionInfo.java

@@ -18,13 +18,35 @@
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
+import com.google.cloud.pubsub.spi.v1.PublisherApi;
+import com.google.cloud.pubsub.spi.v1.SubscriberApi;
 import com.google.common.base.MoreObjects;
 
 import java.io.Serializable;
 import java.util.Objects;
+import java.util.concurrent.TimeUnit;
 
 /**
- * Pub/Sub subscription information.
+ * A Google Cloud Pub/Sub subscription. A subscription represents the stream of messages from a
+ * single, specific topic, to be delivered to the subscribing application. Pub/Sub subscriptions
+ * support both push and pull message delivery.
+ *
+ * <p>In a push subscription, the Pub/Sub server sends a request to the subscriber application, at a
+ * preconfigured endpoint (see {@link PushConfig}). The subscriber's HTTP response serves as an
+ * implicit acknowledgement: a success response indicates that the message has been succesfully
+ * processed and the Pub/Sub system can delete it from the subscription; a non-success response
+ * indicates that the Pub/Sub server should resend it (implicit "nack").
+ *
+ * <p>In a pull subscription, the subscribing application must explicitly pull messages using one of
+ * {@link PubSub#pull(String, PubSub.PullOption...)},
+ * {@link PubSub#pullAsync(String, PubSub.MessageProcessor)} or
+ * {@link PubSub#pullAsync(String, PubSub.PullOption...)}. The subscribing application must then
+ * explicitly acknowledge the messages using one of {@link PubSub#ack(String, Iterable)},
+ * {@link PubSub#ack(String, String, String...)}, {@link PubSub#ackAsync(String, Iterable)} or
+ * {@link PubSub#ackAsync(String, String, String...)}.
+ *
+ * @see <a href="https://cloud.google.com/pubsub/overview#data_model">Pub/Sub Data Model</a>
+ * @see <a href="https://cloud.google.com/pubsub/subscriber">Subscriber Guide</a>
  */
 public class SubscriptionInfo implements Serializable {
 
@@ -35,20 +57,47 @@ public class SubscriptionInfo implements Serializable {
   private final PushConfig pushConfig;
   private final int ackDeadlineSeconds;
 
-
   /**
-   * Builder for Subscription.
+   * Builder for {@code SubscriptionInfo} objects.
    */
   public abstract static class Builder {
 
+    /**
+     * Sets the name of the subscription. The name must start with a letter, and contain only
+     * letters ({@code [A-Za-z]}), numbers ({@code [0-9]}), dashes ({@code -}), underscores
+     * ({@code _}), periods ({@code .}), tildes ({@code ~}), plus ({@code +}) or percent signs
+     * ({@code %}). It must be between 3 and 255 characters in length and cannot begin with the
+     * string {@code goog}.
+     */
     public abstract Builder name(String name);
 
+    /**
+     * Sets the name of the topic the subscription refers to.
+     */
     public abstract Builder topic(String name);
 
+    /**
+     * Sets the push configuration for the subscription. If set, the subscription will be in
+     * push mode and the {@code pushConfig} parameter provides the push endpoint. If not set, the
+     * subscription will be in pull mode.
+     */
     public abstract Builder pushConfig(PushConfig pushConfig);
 
+    /**
+     * Sets the maximum time after a subscriber receives a message before the subscriber should
+     * acknowledge the message. After message delivery but before the ack deadline expires and
+     * before the message is acknowledged, it is an outstanding message and will not be delivered
+     * again during that time (on a best-effort basis). For pull subscriptions, this value is used
+     * as the initial value for the ack deadline. To override the ack deadline value for a given
+     * message, use {@link PubSub#modifyAckDeadline(String, int, TimeUnit, Iterable)}. For push
+     * delivery, this value is used to set the request timeout for the call to the push endpoint. If
+     * not specified, the default value of 10 seconds is used.
+     */
     public abstract Builder ackDeadLineSeconds(int ackDeadLineSeconds);
 
+    /**
+     * Creates a subscription object.
+     */
     public abstract SubscriptionInfo build();
   }
 
@@ -108,31 +157,60 @@ public SubscriptionInfo build() {
     ackDeadlineSeconds = builder.ackDeadlineSeconds;
   }
 
+  /**
+   * Returns the name of the topic this subscription refers to.
+   */
   public String topic() {
     return topic;
   }
 
+  /**
+   * Sets the name of the subscription. The name must start with a letter, and contain only
+   * letters ({@code [A-Za-z]}), numbers ({@code [0-9]}), dashes ({@code -}), underscores
+   * ({@code _}), periods ({@code .}), tildes ({@code ~}), plus ({@code +}) or percent signs
+   * ({@code %}). It must be between 3 and 255 characters in length and cannot begin with the
+   * string {@code goog}.
+   */
   public String name() {
     return name;
   }
 
+  /**
+   * Returns the push configuration for the subscription. If set, the subscription is in push mode
+   * and the returned value defines the push endpoint. If {@code null}, the subscription is in pull
+   * mode.
+   */
   public PushConfig pushConfig() {
     return pushConfig;
   }
 
+  /**
+   * Returns the maximum time after a subscriber receives a message before the subscriber should
+   * acknowledge the message. After message delivery but before the ack deadline expires and
+   * before the message is acknowledged, it is an outstanding message and will not be delivered
+   * again during that time (on a best-effort basis). For pull subscriptions, this value is used
+   * as the initial value for the ack deadline. To override the ack deadline value for a given
+   * message, use {@link PubSub#modifyAckDeadline(String, int, TimeUnit, Iterable)}. For push
+   * delivery, this value is used to set the request timeout for the call to the push endpoint. If
+   * not specified, the default value of 10 seconds is used.
+   */
   public long ackDeadlineSeconds() {
     return ackDeadlineSeconds;
   }
 
   @Override
-  public boolean equals(Object o) {
-    if (this == o) {
+  public boolean equals(Object obj) {
+    if (this == obj) {
       return true;
     }
-    if (o == null || getClass() != o.getClass()) {
+    if (obj == null || !obj.getClass().equals(this.getClass())) {
       return false;
     }
-    return Objects.equals(toPb(), ((SubscriptionInfo) o).toPb());
+    SubscriptionInfo other = (SubscriptionInfo) obj;
+    return Objects.equals(topic, other.topic)
+        && Objects.equals(name, other.name)
+        && Objects.equals(pushConfig, other.pushConfig)
+        && ackDeadlineSeconds == other.ackDeadlineSeconds;
   }
 
   @Override
@@ -150,11 +228,11 @@ public String toString() {
         .toString();
   }
 
-  com.google.pubsub.v1.Subscription toPb() {
+  com.google.pubsub.v1.Subscription toPb(String projectId) {
     com.google.pubsub.v1.Subscription.Builder builder =
         com.google.pubsub.v1.Subscription.newBuilder();
-    builder.setTopic(topic);
-    builder.setName(name);
+    builder.setTopic(PublisherApi.formatTopicName(projectId, topic));
+    builder.setName(SubscriberApi.formatSubscriptionName(projectId, name));
     builder.setAckDeadlineSeconds(ackDeadlineSeconds);
     if (pushConfig != null) {
       builder.setPushConfig(pushConfig.toPb());
@@ -163,26 +241,67 @@ com.google.pubsub.v1.Subscription toPb() {
   }
 
   static SubscriptionInfo fromPb(com.google.pubsub.v1.Subscription subscription) {
-    Builder builder = builder(subscription.getTopic(), subscription.getName());
+    Builder builder = builder(PublisherApi.parseTopicFromTopicName(subscription.getTopic()),
+        SubscriberApi.parseSubscriptionFromSubscriptionName(subscription.getName()));
     builder.ackDeadLineSeconds(subscription.getAckDeadlineSeconds());
-    if (subscription.hasPushConfig()) {
+    // A subscription with an "empty" push config is a pull subscription
+    if (subscription.hasPushConfig()
+        && !subscription.getPushConfig().getPushEndpoint().equals("")) {
       builder.pushConfig(PushConfig.fromPb(subscription.getPushConfig()));
     }
     return builder.build();
   }
 
+  /**
+   * Returns a builder for the subscription object.
+   */
   public Builder toBuilder() {
     return new BuilderImpl(this);
   }
 
+  /**
+   * Creates a pull {@code SubscriptionInfo} object given the name of the topic and the name of the
+   * subscription.
+   *
+   * @param topic the name of the topic the subscription refers to
+   * @param name the name of the subscription. The name must start with a letter, and contain only
+   *     letters ({@code [A-Za-z]}), numbers ({@code [0-9]}), dashes ({@code -}), underscores
+   *     ({@code _}), periods ({@code .}), tildes ({@code ~}), plus ({@code +}) or percent signs
+   *     ({@code %}). It must be between 3 and 255 characters in length and cannot begin with the
+   *     string {@code goog}
+   */
   public static SubscriptionInfo of(String topic, String name) {
     return builder(topic, name).build();
   }
 
+  /**
+   * Creates a push {@code SubscriptionInfo} object given the name of the topic, the name of the
+   * subscription and the push endpoint.
+   *
+   * @param topic the name of the topic the subscription refers to
+   * @param name the name of the subscription. The name must start with a letter, and contain only
+   *     letters ({@code [A-Za-z]}), numbers ({@code [0-9]}), dashes ({@code -}), underscores
+   *     ({@code _}), periods ({@code .}), tildes ({@code ~}), plus ({@code +}) or percent signs
+   *     ({@code %}). It must be between 3 and 255 characters in length and cannot begin with the
+   *     string {@code goog}
+   * @param endpoint a URL locating the endpoint to which messages should be pushed. For example,
+   *     an endpoint might use {@code https://example.com/push}.
+   */
   public static SubscriptionInfo of(String topic, String name, String endpoint) {
     return builder(topic, name).pushConfig(PushConfig.of(endpoint)).build();
   }
 
+  /**
+   * Creates a builder for {@code SubscriptionInfo} objects given the name of the topic and the name
+   * of the subscription.
+   *
+   * @param topic the name of the topic the subscription refers to
+   * @param name the name of the subscription. The name must start with a letter, and contain only
+   *     letters ({@code [A-Za-z]}), numbers ({@code [0-9]}), dashes ({@code -}), underscores
+   *     ({@code _}), periods ({@code .}), tildes ({@code ~}), plus ({@code +}) or percent signs
+   *     ({@code %}). It must be between 3 and 255 characters in length and cannot begin with the
+   *     string {@code goog}
+   */
   public static Builder builder(String topic, String name) {
     return new BuilderImpl(topic, name);
   }

gcloud-java-pubsub/src/main/java/com/google/cloud/pubsub/TopicInfo.java

@@ -126,6 +126,9 @@ static TopicInfo fromPb(com.google.pubsub.v1.Topic topicPb) {
     return builder(PublisherApi.parseTopicFromTopicName(topicPb.getName())).build();
   }
 
+  /**
+   * Returns a builder for the topic object.
+   */
   public Builder toBuilder() {
     return new BuilderImpl(this);
   }
@@ -137,7 +140,7 @@ public Builder toBuilder() {
    *     ({@code [A-Za-z]}), numbers ({@code [0-9]}), dashes ({@code -}), underscores ({@code _}),
    *     periods ({@code .}), tildes ({@code ~}), plus ({@code +}) or percent signs ({@code %}).
    *     It must be between 3 and 255 characters in length and cannot begin with the string
-   *     {@code goog}.
+   *     {@code goog}
    */
   public static TopicInfo of(String name) {
     return builder(name).build();
@@ -150,7 +153,7 @@ public static TopicInfo of(String name) {
    *     ({@code [A-Za-z]}), numbers ({@code [0-9]}), dashes ({@code -}), underscores ({@code _}),
    *     periods ({@code .}), tildes ({@code ~}), plus ({@code +}) or percent signs ({@code %}).
    *     It must be between 3 and 255 characters in length and cannot begin with the string
-   *     {@code goog}.
+   *     {@code goog}
    */
   public static Builder builder(String name) {
     return new BuilderImpl(name);

gcloud-java-pubsub/src/test/java/com/google/cloud/pubsub/SubscriptionInfoTest.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright 2016 Google Inc. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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.google.cloud.pubsub;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+import org.junit.Test;
+
+public class SubscriptionInfoTest {
+
+  private static final String TOPIC = "topic";
+  private static final String NAME = "subscription";
+  private static final String ENDPOINT = "https://example.com/push";
+  private static final PushConfig PUSH_CONFIG = PushConfig.of(ENDPOINT);
+  private static final int ACK_DEADLINE = 42;
+  private static final SubscriptionInfo SUBSCRIPTION_INFO = SubscriptionInfo.builder(TOPIC, NAME)
+      .pushConfig(PUSH_CONFIG)
+      .ackDeadLineSeconds(ACK_DEADLINE)
+      .build();
+
+  @Test
+  public void testToBuilder() {
+    compareSubscriptionInfo(SUBSCRIPTION_INFO, SUBSCRIPTION_INFO.toBuilder().build());
+    SubscriptionInfo subscriptionInfo = SUBSCRIPTION_INFO.toBuilder()
+        .topic("newTopic")
+        .name("newSubscription")
+        .build();
+    assertEquals("newTopic", subscriptionInfo.topic());
+    assertEquals("newSubscription", subscriptionInfo.name());
+    subscriptionInfo = subscriptionInfo.toBuilder().name(NAME).topic(TOPIC).build();
+    compareSubscriptionInfo(SUBSCRIPTION_INFO, subscriptionInfo);
+  }
+
+  @Test
+  public void testBuilder() {
+    assertEquals(TOPIC, SUBSCRIPTION_INFO.topic());
+    assertEquals(NAME, SUBSCRIPTION_INFO.name());
+    assertEquals(PUSH_CONFIG, SUBSCRIPTION_INFO.pushConfig());
+    assertEquals(ACK_DEADLINE, SUBSCRIPTION_INFO.ackDeadlineSeconds());
+  }
+
+  @Test
+  public void testOf() {
+    SubscriptionInfo subscriptionInfo = SubscriptionInfo.of(TOPIC, NAME);
+    assertEquals(TOPIC, subscriptionInfo.topic());
+    assertEquals(NAME, subscriptionInfo.name());
+    assertNull(subscriptionInfo.pushConfig());
+    assertEquals(0, subscriptionInfo.ackDeadlineSeconds());
+    subscriptionInfo = SubscriptionInfo.of(TOPIC, NAME, ENDPOINT);
+    assertEquals(TOPIC, subscriptionInfo.topic());
+    assertEquals(NAME, subscriptionInfo.name());
+    assertEquals(PushConfig.of(ENDPOINT), subscriptionInfo.pushConfig());
+    assertEquals(0, subscriptionInfo.ackDeadlineSeconds());
+  }
+
+  @Test
+  public void testToAndFromPb() {
+    compareSubscriptionInfo(SUBSCRIPTION_INFO,
+        SubscriptionInfo.fromPb(SUBSCRIPTION_INFO.toPb("project")));
+    SubscriptionInfo subscriptionInfo = SubscriptionInfo.of(TOPIC, NAME);
+    compareSubscriptionInfo(subscriptionInfo,
+        SubscriptionInfo.fromPb(subscriptionInfo.toPb("project")));
+    subscriptionInfo = SubscriptionInfo.of(TOPIC, NAME, ENDPOINT);
+    compareSubscriptionInfo(subscriptionInfo,
+        SubscriptionInfo.fromPb(subscriptionInfo.toPb("project")));
+  }
+
+  private void compareSubscriptionInfo(SubscriptionInfo expected, SubscriptionInfo value) {
+    assertEquals(expected, value);
+    assertEquals(expected.topic(), value.topic());
+    assertEquals(expected.name(), value.name());
+    assertEquals(expected.pushConfig(), value.pushConfig());
+    assertEquals(expected.ackDeadlineSeconds(), value.ackDeadlineSeconds());
+    assertEquals(expected.hashCode(), value.hashCode());
+  }
+}