Refactor Transaction and Dataset into DatastoreRequest

lib/datastore/dataset.js

@@ -55,6 +55,7 @@ var Transaction = require('./transaction.js');
  * @private
  */
 var util = require('../common/util.js');
+var nodeutil = require('util');
 
 /**
  * Scopes for Google Datastore access.
@@ -66,6 +67,8 @@ var SCOPES = [
   'https://www.googleapis.com/auth/userinfo.email'
 ];
 
+var DatastoreRequest = require('./datastore_request.js');
+
 /**
  * Interact with a dataset from the
  * [Google Cloud Datastore]{@link https://developers.google.com/datastore/}.
@@ -101,11 +104,13 @@ function Dataset(options) {
     keyFilename: options.keyFilename,
     scopes: SCOPES
   });
+
   this.projectId = options.projectId;
   this.namespace = options.namespace;
-  this.transaction = this.createTransaction_();
 }
 
+nodeutil.inherits(Dataset, DatastoreRequest);
+
 /**
  * Helper to create a Key object, scoped to the dataset's namespace by default.
  *
@@ -166,117 +171,6 @@ Dataset.prototype.createQuery = function(namespace, kinds) {
   return new Query(namespace, util.arrayize(kinds));
 };
 
-/**
- * Retrieve the entities identified with the specified key(s) in the current
- * transaction. Get operations require a valid key to retrieve the
- * key-identified entity from Datastore.
- *
- * @borrows {module:datastore/transaction#get} as get
- *
- * @param {Key|Key[]} key - Datastore key object(s).
- * @param {function} callback - The callback function.
- *
- * @example
- * dataset.get([
- *   dataset.key(['Company', 123]),
- *   dataset.key(['Product', 'Computer'])
- * ], function(err, entities) {});
- */
-Dataset.prototype.get = function(key, callback) {
-  this.transaction.get(key, callback);
-};
-
-/**
- * Insert or update the specified object(s) in the current transaction. If a
- * key is incomplete, its associated object is inserted and its generated
- * identifier is returned to the callback.
- *
- * @borrows {module:datastore/transaction#save} as save
- *
- * @param {object|object[]} entities - Datastore key object(s).
- * @param {Key} entities.key - Datastore key object.
- * @param {object} entities.data - Data to save with the provided key.
- * @param {function} callback - The callback function.
- *
- * @example
- * // Save a single entity.
- * dataset.save({
- *   key: dataset.key('Company'),
- *   data: {
- *     rating: '10'
- *   }
- * }, function(err, key) {
- *   // Because we gave an incomplete key as an argument, `key` will be
- *   // populated with the complete, generated key.
- * });
- *
- * // Save multiple entities at once.
- * dataset.save([
- *   {
- *     key: dataset.key(['Company', 123]),
- *     data: {
- *       HQ: 'Dallas, TX'
- *     }
- *   },
- *   {
- *     key: dataset.key(['Product', 'Computer']),
- *     data: {
- *       vendor: 'Dell'
- *     }
- *   }
- * ], function(err, keys) {});
- */
-Dataset.prototype.save = function(key, obj, callback) {
-  this.transaction.save(key, obj, callback);
-};
-
-/**
- * Delete all entities identified with the specified key(s) in the current
- * transaction.
- *
- * @param {Key|Key[]} key - Datastore key object(s).
- * @param {function} callback - The callback function.
- *
- * @borrows {module:datastore/transaction#delete} as delete
- *
- * @example
- * // Delete a single entity.
- * dataset.delete(dataset.key(['Company', 123]), function(err) {});
- *
- * // Delete multiple entities at once.
- * dataset.delete([
- *   dataset.key(['Company', 123]),
- *   dataset.key(['Product', 'Computer'])
- * ], function(err) {});
- */
-Dataset.prototype.delete = function(key, callback) {
-  this.transaction.delete(key, callback);
-};
-
-/**
- * Datastore allows you to query entities by kind, filter them by property
- * filters, and sort them by a property name. Projection and pagination are also
- * supported. If more results are available, a query to retrieve the next page
- * is provided to the callback function.
- *
- * @borrows {module:datastore/transaction#runQuery} as runQuery
- *
- * @param {module:datastore/query} query - Query object.
- * @param {function} callback - The callback function.
- *
- * @example
- * // Retrieve 5 companies.
- * dataset.runQuery(queryObject, function(err, entities, nextQuery) {
- *   // `nextQuery` is not null if there are more results.
- *   if (nextQuery) {
- *     dataset.runQuery(nextQuery, function(err, entities, nextQuery) {});
- *   }
- * });
- */
-Dataset.prototype.runQuery = function(q, callback) {
-  this.transaction.runQuery(q, callback);
-};
-
 /**
  * Run a function in the context of a new transaction. Transactions allow you to
  * perform multiple operations, committing your changes atomically.
@@ -342,7 +236,8 @@ Dataset.prototype.allocateIds = function(incompleteKey, n, callback) {
   for (var i = 0; i < n; i++) {
     incompleteKeys.push(entity.keyToKeyProto(incompleteKey));
   }
-  this.transaction.makeReq(
+
+  this.createRequest(
       'allocateIds',
       new pb.AllocateIdsRequest({ key: incompleteKeys }),
       pb.AllocateIdsResponse, function(err, resp) {
@@ -358,12 +253,6 @@ Dataset.prototype.allocateIds = function(incompleteKey, n, callback) {
   });
 };
 
-/**
- * Create a new Transaction object using the existing connection and dataset.
- *
- * @return {module:datastore/transaction}
- * @private
- */
 Dataset.prototype.createTransaction_ = function() {
   return new Transaction(this.connection, this.projectId);
 };