remove topic.options.autoCreate, add topic.getMetadata

lib/pubsub/index.js

@@ -174,9 +174,9 @@ PubSub.prototype.getTopics = function(query, callback) {
       return;
     }
     var topics = (result.topics || []).map(function(item) {
-      return new Topic(self, {
-        name: item.name
-      });
+      var topicInstance = self.topic(item.name);
+      topicInstance.metadata = item;
+      return topicInstance;
     });
     var nextQuery = null;
     if (result.nextPageToken) {
@@ -199,16 +199,10 @@ PubSub.prototype.getTopics = function(query, callback) {
  *
  * @example
  * pubsub.createTopic('my-new-topic', function(err, topic, apiResponse) {
- *   topic.publish({
- *     data: 'New message!'
- *   }, function(err) {});
+ *   if (!err) {
+ *     // The topic was created successfully.
+ *   }
  * });
- *
- * //-
- * // <strong>Note:</strong> For cases like the one above, it is simpler to use
- * // {module:pubsub#topic}, which will create the topic for you at the time you
- * // publish a message.
- * //-
  */
 PubSub.prototype.createTopic = function(name, callback) {
   callback = callback || util.noop;
@@ -359,56 +353,27 @@ PubSub.prototype.subscription = function(name, options) {
 };
 
 /**
- * Create a Topic object to reference an existing topic.
+ * Create a Topic object to reference an existing topic. See
+ * {module:pubsub/createTopic} to create a topic.
  *
  * @throws {Error} If a name is not provided.
  *
  * @param {string} name - The name of the topic.
- * @param {object=} options - Configuration object.
- * @param {boolean} options.autoCreate - Automatically create topic if it
- *     doesn't exist. Note that messages published to a topic with no
- *     subscribers will not be delivered. Default: true.
  * @return {module:pubsub/topic}
  *
  * @example
- * //-
- * // By default, it isn't required to specify a topic that already exists. The
- * // first time you publish a message, the topic will be created for you.
- * //
- * // This will only cost one additional API request at the time of publishing.
- * // If the topic doesn't need to be created, there is no performance penalty.
- * //-
- * var topic = pubsub.topic('my-topic');
+ * var topic = pubsub.topic('my-existing-topic');
  *
  * topic.publish({
  *   data: 'New message!'
  * }, function(err) {});
- *
- * //-
- * // If you prefer an error when trying to publish to a topic that doesn't
- * // exist, set `autoCreate` to `false`.
- * //-
- * var nonExistentTopic = pubsub.topic('my-non-existent-topic', {
- *   autoCreate: false
- * });
- *
- * nonExistentTopic.publish({
- *   data: 'New message!'
- * }, function(err) {
- *   if (err) {
- *     // API error from trying to publish a message to a non-existent topic.
- *   }
- * });
  */
-PubSub.prototype.topic = function(name, options) {
+PubSub.prototype.topic = function(name) {
   if (!name) {
     throw new Error('A name must be specified for a new topic.');
   }
-  options = options || {};
-  return new Topic(this, {
-    name: name,
-    autoCreate: options.autoCreate
-  });
+
+  return new Topic(this, name);
 };
 
 /**

lib/pubsub/topic.js

@@ -29,11 +29,7 @@ var util = require('../common/util.js');
 /*! Developer Documentation
  *
  * @param {module:pubsub} pubsub - PubSub object.
- * @param {object} options - Configuration object.
- * @param {boolean=} options.autoCreate - Automatically create topic if it
- *     doesn't exist. Note that messages published to a topic with no
- *     subscribers will not be delivered. Default: true.
- * @param {string} options.name - Name of the topic.
+ * @param {string} name - Name of the topic.
  */
 /**
  * A Topic object allows you to interact with a Google Cloud Pub/Sub topic.
@@ -48,13 +44,14 @@ var util = require('../common/util.js');
  *
  * var topic = pubsub.topic('my-topic');
  */
-function Topic(pubsub, options) {
-  this.autoCreate = options.autoCreate !== false;
-  this.name = Topic.formatName_(pubsub.projectId, options.name);
+function Topic(pubsub, name) {
+  this.name = Topic.formatName_(pubsub.projectId, name);
 
   this.projectId = pubsub.projectId;
   this.pubsub = pubsub;
-  this.unformattedName = options.name;
+  this.unformattedName = name;
+
+  this.makeReq_ = this.pubsub.makeReq_.bind(this.pubsub);
 }
 
 /**
@@ -181,6 +178,28 @@ Topic.prototype.delete = function(callback) {
   this.makeReq_('DELETE', this.name, null, null, callback);
 };
 
+/**
+ * Get the official representation of this topic from the API.
+ *
+ * @param {function} callback - The callback function.
+ * @param {?error} callback.err - An error returned while making this request.
+ * @param {object} callback.metadata - The metadata of the Topic.
+ * @param {object} callback.apiResponse - The full API response.
+ */
+Topic.prototype.getMetadata = function(callback) {
+  var self = this;
+
+  this.makeReq_('GET', this.name, null, null, function(err, resp) {
+    if (err) {
+      callback(err, null, resp);
+      return;
+    }
+
+    self.metadata = resp;
+    callback(null, self.metadata, resp);
+  });
+};
+
 /**
  * Get a list of the subscriptions registered to this topic. You may optionally
  * provide a query object as the first argument to customize the response.
@@ -305,40 +324,4 @@ Topic.prototype.subscription = function(name, options) {
   return this.pubsub.subscription(name, options);
 };
 
-/**
- * Make an API request using the parent PubSub object's `makeReq_`. If the Topic
- * instance has `autoCreate: true` set, this method will first try to create the
- * Topic in the event of a 404.
- *
- * @private
- *
- * @param {string} method - Action.
- * @param {string} path - Request path.
- * @param {*} query - Request query object.
- * @param {*} body - Request body contents.
- * @param {function} callback - The callback function.
- */
-Topic.prototype.makeReq_ = function(method, path, query, body, callback) {
-  var self = this;
-
-  function createTopicThenRetryRequest() {
-    self.pubsub.createTopic(self.unformattedName, function(err, topic, res) {
-      if (err) {
-        callback(err, null, res);
-        return;
-      }
-
-      self.pubsub.makeReq_(method, path, query, body, callback);
-    });
-  }
-
-  this.pubsub.makeReq_(method, path, query, body, function(err, res) {
-    if (self.autoCreate && err && err.code === 404 && method !== 'DELETE') {
-      createTopicThenRetryRequest();
-    } else {
-      callback(err, res);
-    }
-  });
-};
-
 module.exports = Topic;

system-test/pubsub.js

@@ -115,30 +115,20 @@ describe('pubsub', function() {
       });
     });
 
-    it('should lazily create by default', function(done) {
-      var newTopicName = generateTopicName();
-      var newTopic = pubsub.topic(newTopicName);
-
-      newTopic.publish({ data: 'message from me' }, function(err) {
+    it('should publish a message', function(done) {
+      var topic = pubsub.topic(TOPIC_NAMES[0]);
+      topic.publish({ data: 'message from me' }, function(err, messageIds) {
         assert.ifError(err);
-
-        pubsub.getTopics(function(err, topics) {
-          assert.ifError(err);
-
-          assert(topics.some(function(topic) {
-            return topic.name.indexOf(newTopicName) > -1;
-          }));
-
-          newTopic.delete(done);
-        });
+        assert.equal(messageIds.length, 1);
+        done();
       });
     });
 
-    it('should publish a message', function(done) {
+    it('should get the metadata of a topic', function(done) {
       var topic = pubsub.topic(TOPIC_NAMES[0]);
-      topic.publish({ data: 'message from me' }, function(err, messageIds) {
+      topic.getMetadata(function(err, metadata) {
         assert.ifError(err);
-        assert.equal(messageIds.length, 1);
+        assert.strictEqual(metadata.name, topic.name);
         done();
       });
     });

test/pubsub/index.js

@@ -99,9 +99,12 @@ describe('PubSub', function() {
   });
 
   describe('getTopics', function() {
+    var topicName = 'fake-topic';
+    var apiResponse = { topics: [{ name: topicName }]};
+
     beforeEach(function() {
       pubsub.makeReq_ = function(method, path, q, body, callback) {
-        callback(null, { topics: [{ name: 'fake-topic' }] });
+        callback(null, apiResponse);
       };
     });
 
@@ -121,10 +124,19 @@ describe('PubSub', function() {
       pubsub.getTopics(function() {});
     });
 
-    it('should return Topic instances', function() {
+    it('should return Topic instances with metadata', function(done) {
+      var topic = {};
+
+      pubsub.topic = function(name) {
+        assert.strictEqual(name, topicName);
+        return topic;
+      };
+
       pubsub.getTopics(function(err, topics) {
         assert.ifError(err);
-        assert(topics[0] instanceof Topic);
+        assert.strictEqual(topics[0], topic);
+        assert.strictEqual(topics[0].metadata, apiResponse.topics[0]);
+        done();
       });
     });
 
@@ -237,7 +249,7 @@ describe('PubSub', function() {
         'projects/' + PROJECT_ID + '/topics/' + TOPIC_NAME + '/subscriptions';
 
       before(function() {
-        TOPIC = new Topic(pubsub, { name: TOPIC_NAME });
+        TOPIC = new Topic(pubsub, TOPIC_NAME);
       });
 
       it('should subscribe to a topic by string', function(done) {