Cleans up code associated with callbacks

- Replaces usage of the local callback() func with lodash.noop - Renames callback arguments to confirm with Google style guide

Author: Tim Emiola

lib/auth/jwtclient.js

@@ -19,8 +19,10 @@
 var Auth2Client = require('./oauth2client.js');
 var gToken = require('gtoken');
 var JWTAccess = require('./jwtaccess.js');
+var noop = require('lodash.noop');
 var util = require('util');
 
+
 /**
  * JWT service account credentials.
  *
@@ -53,13 +55,6 @@ function JWT(email, keyFile, key, scopes, subject) {
  */
 util.inherits(JWT, Auth2Client);
 
-// Executes the given callback if it is not null.
-function callback(c, err, res) {
- if (c) {
- c(err, res);
- }
-}
-
 /**
  * Creates a copy of the credential with the specified scopes.
  * @param {(string|array)=} scopes List of requested scopes or a single scope.
@@ -73,16 +68,16 @@ JWT.prototype.createScoped = function(scopes) {
  * Obtains the metadata to be sent with the request.
  *
  * @param {string} opt_uri the URI being authorized.
- * @param {function} cb_with_metadata
+ * @param {function} metadataFn
  */
-JWT.prototype.getRequestMetadata = function(opt_uri, cb_with_metadata) {
+JWT.prototype.getRequestMetadata = function(opt_uri, metadataFn) {
  if (this.createScopedRequired() && opt_uri) {
  // no scopes have been set, but a uri has been provided. Use JWTAccess credentials.
  var alt = new JWTAccess(this.email, this.key);
- alt.getRequestMetadata(opt_uri, cb_with_metadata);
+ alt.getRequestMetadata(opt_uri, metadataFn);
  } else {
  JWT.super_.prototype.getRequestMetadata.call(
- this, opt_uri, cb_with_metadata);
+ this, opt_uri, metadataFn);
  }
 };
 
@@ -112,6 +107,7 @@ JWT.prototype.createScopedRequired = function() {
  */
 JWT.prototype.authorize = function(opt_callback) {
  var that = this;
+ var done = opt_callback || noop;
 
  that.refreshToken_(null, function(err, result) {
  if (!err) {
@@ -120,7 +116,7 @@ JWT.prototype.authorize = function(opt_callback) {
  that.key = that.gtoken.key;
  that.email = that.gtoken.iss;
  }
- callback(opt_callback, err, result);
+ done(err, result);
  });
 };
 
@@ -132,12 +128,14 @@ JWT.prototype.authorize = function(opt_callback) {
  * @private
  */
 JWT.prototype.refreshToken_ = function(ignored_, opt_callback) {
+ var done = opt_callback || noop;
+
  this._createGToken(function(err, gToken) {
  if (err) {
- callback(opt_callback, err);
+ done(err);
  } else {
  gToken.getToken(function (err, token) {
- callback(opt_callback, err, {
+ done(err, {
  access_token: token,
  token_type: 'Bearer',
  expiry_date: gToken.expires_at
@@ -155,25 +153,26 @@ JWT.prototype.refreshToken_ = function(ignored_, opt_callback) {
  */
 JWT.prototype.fromJSON = function(json, opt_callback) {
  var that = this;
+ var done = opt_callback || noop;
  if (!json) {
- callback(opt_callback, new Error(
+ done(new Error(
  'Must pass in a JSON object containing the service account auth settings.'));
  return;
  }
  if (!json.client_email) {
- callback(opt_callback, new Error(
+ done(new Error(
  'The incoming JSON object does not contain a client_email field'));
  return;
  }
  if (!json.private_key) {
- callback(opt_callback, new Error(
+ done(new Error(
  'The incoming JSON object does not contain a private_key field'));
  return;
  }
  // Extract the relevant information from the json key file.
  that.email = json.client_email;
  that.key = json.private_key;
- callback(opt_callback);
+ done();
 };
 
 /**
@@ -183,10 +182,11 @@ JWT.prototype.fromJSON = function(json, opt_callback) {
  */
 JWT.prototype.fromStream = function(stream, opt_callback) {
  var that = this;
+ var done = opt_callback || noop;
+
  if (!stream) {
  process.nextTick(function() {
- callback(
- opt_callback,
+ done(
  new Error('Must pass in a stream containing the service account auth settings.'));
  });
  return;
@@ -201,7 +201,7 @@ JWT.prototype.fromStream = function(stream, opt_callback) {
  var data = JSON.parse(s);
  that.fromJSON(data, opt_callback);
  } catch (err) {
- callback(opt_callback, err);
+ done(err);
  }
  });
 };