diff --git a/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache b/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
index c55fbfd393d..6ef0a6a9dc5 100644
--- a/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/Javascript/ApiClient.mustache
@@ -208,7 +208,9 @@
     // See http://visionmedia.github.io/superagent/#parsing-response-bodies
     var data = response.body;
     if (data == null) {
-      return null;
+      // Superagent does not always produce a body; use the unparsed response
+      // as a fallback
+      data = response.text;
     }
     return ApiClient.convertToType(data, returnType);
   };
diff --git a/samples/client/petstore/javascript-promise/package.json b/samples/client/petstore/javascript-promise/package.json
index 1fdf78cf217..72a48ac71de 100644
--- a/samples/client/petstore/javascript-promise/package.json
+++ b/samples/client/petstore/javascript-promise/package.json
@@ -12,6 +12,7 @@
   },
   "devDependencies": {
     "mocha": "~2.3.4",
+    "sinon": "1.17.3",
     "expect.js": "~0.3.1"
   }
 }
diff --git a/samples/client/petstore/javascript-promise/src/ApiClient.js b/samples/client/petstore/javascript-promise/src/ApiClient.js
index 353494ea941..a0c70eb10ee 100644
--- a/samples/client/petstore/javascript-promise/src/ApiClient.js
+++ b/samples/client/petstore/javascript-promise/src/ApiClient.js
@@ -21,6 +21,15 @@
      */
     this.basePath = 'http://petstore.swagger.io/v2'.replace(/\/+$/, '');
 
+    this.authentications = {
+      'petstore_auth': {type: 'oauth2'},
+      'test_api_client_id': {type: 'apiKey', in: 'header', name: 'x-test_api_client_id'},
+      'test_api_client_secret': {type: 'apiKey', in: 'header', name: 'x-test_api_client_secret'},
+      'api_key': {type: 'apiKey', in: 'header', name: 'api_key'},
+      'test_api_key_query': {type: 'apiKey', in: 'query', name: 'test_api_key_query'},
+      'test_api_key_header': {type: 'apiKey', in: 'header', name: 'test_api_key_header'}
+    };
+
     /**
      * The default HTTP headers to be included for all API calls.
      */
@@ -158,6 +167,42 @@
     }
   };
 
+  ApiClient.prototype.applyAuthToRequest = function applyAuthToRequest(request, authNames) {
+    var _this = this;
+    authNames.forEach(function(authName) {
+      var auth = _this.authentications[authName];
+      switch (auth.type) {
+        case 'basic':
+          if (auth.username || auth.password) {
+            request.auth(auth.username || '', auth.password || '');
+          }
+          break;
+        case 'apiKey':
+          if (auth.apiKey) {
+            var data = {};
+            if (auth.apiKeyPrefix) {
+              data[auth.name] = auth.apiKeyPrefix + ' ' + auth.apiKey;
+            } else {
+              data[auth.name] = auth.apiKey;
+            }
+            if (auth.in === 'header') {
+              request.set(data);
+            } else {
+              request.query(data);
+            }
+          }
+          break;
+        case 'oauth2':
+          if (auth.accessToken) {
+            request.set({'Authorization': 'Bearer ' + auth.accessToken});
+          }
+          break;
+        default:
+          throw new Error('Unknown authentication type: ' + auth.type);
+      }
+    });
+  };
+
   ApiClient.prototype.deserialize = function deserialize(response, returnType) {
     if (response == null || returnType == null) {
       return null;
@@ -166,18 +211,23 @@
     // See http://visionmedia.github.io/superagent/#parsing-response-bodies
     var data = response.body;
     if (data == null) {
-      return null;
+      // Superagent does not always produce a body; use the unparsed response
+      // as a fallback
+      data = response.text;
     }
     return ApiClient.convertToType(data, returnType);
   };
 
   ApiClient.prototype.callApi = function callApi(path, httpMethod, pathParams,
-      queryParams, headerParams, formParams, bodyParam, contentTypes, accepts,
-      returnType) {
+      queryParams, headerParams, formParams, bodyParam, authNames, contentTypes,
+      accepts, returnType) {
     var _this = this;
     var url = this.buildUrl(path, pathParams);
     var request = superagent(httpMethod, url);
 
+    // apply authentications
+    this.applyAuthToRequest(request, authNames);
+
     // set query parameters
     request.query(this.normalizeParams(queryParams));
 
diff --git a/samples/client/petstore/javascript-promise/src/api/PetApi.js b/samples/client/petstore/javascript-promise/src/api/PetApi.js
index d2ece31da91..d6f7bd8275a 100644
--- a/samples/client/petstore/javascript-promise/src/api/PetApi.js
+++ b/samples/client/petstore/javascript-promise/src/api/PetApi.js
@@ -41,6 +41,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = ['application/json', 'application/xml'];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -48,7 +49,7 @@
       return this.apiClient.callApi(
         '/pet', 'PUT',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -73,6 +74,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = ['application/json', 'application/xml'];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -80,7 +82,7 @@
       return this.apiClient.callApi(
         '/pet', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -107,6 +109,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = [Pet];
@@ -114,7 +117,7 @@
       return this.apiClient.callApi(
         '/pet/findByStatus', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -141,6 +144,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = [Pet];
@@ -148,7 +152,7 @@
       return this.apiClient.callApi(
         '/pet/findByTags', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -180,6 +184,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth', 'api_key'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = Pet;
@@ -187,7 +192,7 @@
       return this.apiClient.callApi(
         '/pet/{petId}', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -222,6 +227,7 @@
         'status': status
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = ['application/x-www-form-urlencoded'];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -229,7 +235,7 @@
       return this.apiClient.callApi(
         '/pet/{petId}', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -262,6 +268,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -269,7 +276,7 @@
       return this.apiClient.callApi(
         '/pet/{petId}', 'DELETE',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -304,6 +311,7 @@
         'file': file
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = ['multipart/form-data'];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -311,7 +319,7 @@
       return this.apiClient.callApi(
         '/pet/{petId}/uploadImage', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -343,6 +351,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth', 'api_key'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = 'String';
@@ -350,7 +359,7 @@
       return this.apiClient.callApi(
         '/pet/{petId}?testing_byte_array=true', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -375,6 +384,7 @@
       var formParams = {
       };
 
+      var authNames = ['petstore_auth'];
       var contentTypes = ['application/json', 'application/xml'];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -382,7 +392,7 @@
       return this.apiClient.callApi(
         '/pet?testing_byte_array=true', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
diff --git a/samples/client/petstore/javascript-promise/src/api/StoreApi.js b/samples/client/petstore/javascript-promise/src/api/StoreApi.js
index d6f0503c136..57a3c57d86f 100644
--- a/samples/client/petstore/javascript-promise/src/api/StoreApi.js
+++ b/samples/client/petstore/javascript-promise/src/api/StoreApi.js
@@ -41,6 +41,7 @@
       var formParams = {
       };
 
+      var authNames = ['api_key'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = {'String': 'Integer'};
@@ -48,7 +49,7 @@
       return this.apiClient.callApi(
         '/store/inventory', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -74,6 +75,7 @@
       var formParams = {
       };
 
+      var authNames = ['test_api_client_id', 'test_api_client_secret'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = Order;
@@ -81,7 +83,7 @@
       return this.apiClient.callApi(
         '/store/order', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -113,6 +115,7 @@
       var formParams = {
       };
 
+      var authNames = ['test_api_key_query', 'test_api_key_header'];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = Order;
@@ -120,7 +123,7 @@
       return this.apiClient.callApi(
         '/store/order/{orderId}', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -151,6 +154,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -158,7 +162,7 @@
       return this.apiClient.callApi(
         '/store/order/{orderId}', 'DELETE',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
diff --git a/samples/client/petstore/javascript-promise/src/api/UserApi.js b/samples/client/petstore/javascript-promise/src/api/UserApi.js
index 09f7c9e0d5b..bb93561ec1b 100644
--- a/samples/client/petstore/javascript-promise/src/api/UserApi.js
+++ b/samples/client/petstore/javascript-promise/src/api/UserApi.js
@@ -41,6 +41,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -48,7 +49,7 @@
       return this.apiClient.callApi(
         '/user', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -73,6 +74,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -80,7 +82,7 @@
       return this.apiClient.callApi(
         '/user/createWithArray', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -105,6 +107,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -112,7 +115,7 @@
       return this.apiClient.callApi(
         '/user/createWithList', 'POST',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -141,6 +144,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = 'String';
@@ -148,7 +152,7 @@
       return this.apiClient.callApi(
         '/user/login', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -172,6 +176,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -179,7 +184,7 @@
       return this.apiClient.callApi(
         '/user/logout', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -211,6 +216,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = User;
@@ -218,7 +224,7 @@
       return this.apiClient.callApi(
         '/user/{username}', 'GET',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -250,6 +256,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -257,7 +264,7 @@
       return this.apiClient.callApi(
         '/user/{username}', 'PUT',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
@@ -288,6 +295,7 @@
       var formParams = {
       };
 
+      var authNames = [];
       var contentTypes = [];
       var accepts = ['application/json', 'application/xml'];
       var returnType = null;
@@ -295,7 +303,7 @@
       return this.apiClient.callApi(
         '/user/{username}', 'DELETE',
         pathParams, queryParams, headerParams, formParams, postBody,
-        contentTypes, accepts, returnType
+        authNames, contentTypes, accepts, returnType
       );
       
     }
diff --git a/samples/client/petstore/javascript/src/ApiClient.js b/samples/client/petstore/javascript/src/ApiClient.js
index 11c9ca67ab4..d4377e34d1a 100644
--- a/samples/client/petstore/javascript/src/ApiClient.js
+++ b/samples/client/petstore/javascript/src/ApiClient.js
@@ -211,7 +211,9 @@
     // See http://visionmedia.github.io/superagent/#parsing-response-bodies
     var data = response.body;
     if (data == null) {
-      return null;
+      // Superagent does not always produce a body; use the unparsed response
+      // as a fallback
+      data = response.text;
     }
     return ApiClient.convertToType(data, returnType);
   };