core: allow default method options for service objects

lib/common/service-object.js

@@ -21,6 +21,7 @@
 'use strict';
 
 var exec = require('methmeth');
+var extend = require('extend');
 var is = require('is');
 
 /**
@@ -49,6 +50,9 @@ var util = require('./util.js');
  *     name of a Storage bucket or Pub/Sub topic.
  * @param {object=} config.methods - A map of each method name that should be
  *     inherited.
+ * @param {object} config.methods[].reqOpts - Default request options for this
+ *     particular method. A common use case is when `setMetadata` requires a
+ *     `PUT` method to override the default `PATCH`.
  * @param {object} config.parent - The parent service instance. For example, an
  *     instance of Storage if the object is Bucket.
  */
@@ -61,6 +65,7 @@ function ServiceObject(config) {
   this.parent = config.parent; // Parent class.
   this.id = config.id; // Name or ID (e.g. dataset ID, bucket name, etc.)
   this.createMethod = config.createMethod;
+  this.methods = config.methods || {};
 
   if (config.methods) {
     var allMethodNames = Object.keys(ServiceObject.prototype);
@@ -130,10 +135,12 @@ ServiceObject.prototype.create = function(options, callback) {
  * @param {object} callback.apiResponse - The full API response.
  */
 ServiceObject.prototype.delete = function(callback) {
-  var reqOpts = {
+  var methodConfig = this.methods.delete || {};
+
+  var reqOpts = extend({
     method: 'DELETE',
     uri: ''
-  };
+  }, methodConfig.reqOpts);
 
   callback = callback || util.noop;
 
@@ -225,9 +232,11 @@ ServiceObject.prototype.get = function(config, callback) {
 ServiceObject.prototype.getMetadata = function(callback) {
   var self = this;
 
-  var reqOpts = {
+  var methodConfig = this.methods.getMetadata || {};
+
+  var reqOpts = extend({
     uri: ''
-  };
+  }, methodConfig.reqOpts);
 
   // The `request` method may have been overridden to hold any special behavior.
   // Ensure we call the original `request` method.
@@ -257,11 +266,13 @@ ServiceObject.prototype.setMetadata = function(metadata, callback) {
 
   callback = callback || util.noop;
 
-  var reqOpts = {
+  var methodConfig = this.methods.setMetadata || {};
+
+  var reqOpts = extend(true, {
     method: 'PATCH',
     uri: '',
     json: metadata
-  };
+  }, methodConfig.reqOpts);
 
   // The `request` method may have been overridden to hold any special behavior.
   // Ensure we call the original `request` method.

test/common/service-object.js

@@ -59,6 +59,22 @@ describe('ServiceObject', function() {
       assert.strictEqual(serviceObject.createMethod, CONFIG.createMethod);
     });
 
+    it('should localize the methods', function() {
+      var methods = {};
+
+      var config = extend({}, CONFIG, {
+        methods: methods
+      });
+
+      var serviceObject = new ServiceObject(config);
+
+      assert.strictEqual(serviceObject.methods, methods);
+    });
+
+    it('should default methods to an empty object', function() {
+      assert.deepEqual(serviceObject.methods, {});
+    });
+
     it('should clear out methods that are not asked for', function() {
       var config = extend({}, CONFIG, {
         methods: {
@@ -207,6 +223,27 @@ describe('ServiceObject', function() {
       serviceObject.delete(assert.ifError);
     });
 
+    it('should extend the request options with defaults', function(done) {
+      var method = {
+        reqOpts: {
+          method: 'override',
+          qs: {
+            custom: true
+          }
+        }
+      };
+
+      ServiceObject.prototype.request = function(reqOpts_) {
+        assert.strictEqual(reqOpts_.method, method.reqOpts.method);
+        assert.deepEqual(reqOpts_.qs, method.reqOpts.qs);
+        done();
+      };
+
+      var serviceObject = new ServiceObject(CONFIG);
+      serviceObject.methods.delete = method;
+      serviceObject.delete();
+    });
+
     it('should not require a callback', function() {
       ServiceObject.prototype.request = function(reqOpts, callback) {
         callback();
@@ -384,6 +421,27 @@ describe('ServiceObject', function() {
       serviceObject.getMetadata();
     });
 
+    it('should extend the request options with defaults', function(done) {
+      var method = {
+        reqOpts: {
+          method: 'override',
+          qs: {
+            custom: true
+          }
+        }
+      };
+
+      ServiceObject.prototype.request = function(reqOpts_) {
+        assert.strictEqual(reqOpts_.method, method.reqOpts.method);
+        assert.deepEqual(reqOpts_.qs, method.reqOpts.qs);
+        done();
+      };
+
+      var serviceObject = new ServiceObject(CONFIG);
+      serviceObject.methods.getMetadata = method;
+      serviceObject.getMetadata();
+    });
+
     it('should execute callback with error & apiResponse', function(done) {
       var error = new Error('Error.');
       var apiResponse = {};
@@ -445,6 +503,39 @@ describe('ServiceObject', function() {
       serviceObject.setMetadata(metadata);
     });
 
+    it('should extend the request options with defaults', function(done) {
+      var metadataDefault = {
+        a: 'b'
+      };
+
+      var metadata = {
+        c: 'd'
+      };
+
+      var method = {
+        reqOpts: {
+          method: 'override',
+          qs: {
+            custom: true
+          },
+          json: metadataDefault
+        }
+      };
+
+      var expectedJson = extend(true, {}, metadataDefault, metadata);
+
+      ServiceObject.prototype.request = function(reqOpts_) {
+        assert.strictEqual(reqOpts_.method, method.reqOpts.method);
+        assert.deepEqual(reqOpts_.qs, method.reqOpts.qs);
+        assert.deepEqual(reqOpts_.json, expectedJson);
+        done();
+      };
+
+      var serviceObject = new ServiceObject(CONFIG);
+      serviceObject.methods.setMetadata = method;
+      serviceObject.setMetadata(metadata);
+    });
+
     it('should execute callback with error & apiResponse', function(done) {
       var error = new Error('Error.');
       var apiResponse = {};

test/common/service.js

@@ -32,7 +32,7 @@ util.makeAuthenticatedRequestFactory = function() {
   }
 };
 
-describe('ServiceObject', function() {
+describe('Service', function() {
   var Service;
   var service;