Add support for alt token method. (#285)

Author: Eric Koleda

README.md

@@ -313,6 +313,13 @@ in these requests.
 
 See the [FitBit sample](samples/FitBit.gs) for the complete code.
 
+#### Setting the token HTTP method
+
+Almost all services use the `POST` HTTP method when retrieving the access token,
+but a few services deviate from the spec and use the `PUT` method instead. To
+accomodate those cases you can use the `setTokenMethod()` method to specify the
+HTTP method to use when making the request.
+
 #### Modifying the access token payload
 
 Some OAuth providers, such as the Smartsheet API, require you to

src/Service.js

@@ -33,6 +33,7 @@ var Service_ = function(serviceName) {
   this.params_ = {};
   this.tokenFormat_ = TOKEN_FORMAT.JSON;
   this.tokenHeaders_ = null;
+  this.tokenMethod_ = 'post';
   this.expirationMinutes_ = 60;
 };
 
@@ -106,6 +107,17 @@ Service_.prototype.setTokenHeaders = function(tokenHeaders) {
   return this;
 };
 
+/**
+ * Sets the HTTP method to use when retrieving or refreshing the access token.
+ * Default: "post".
+ * @param {string} tokenMethod The HTTP method to use.
+ * @return {!Service_} This service, for chaining.
+ */
+Service_.prototype.setTokenMethod = function(tokenMethod) {
+  this.tokenMethod_ = tokenMethod;
+  return this;
+};
+
 /**
  * @callback tokenHandler
  * @param tokenPayload {Object} A hash of parameters to be sent to the token
@@ -508,7 +520,7 @@ Service_.prototype.fetchToken_ = function(payload, optUrl) {
     payload = this.tokenPayloadHandler_(payload);
   }
   var response = UrlFetchApp.fetch(url, {
-    method: 'post',
+    method: this.tokenMethod_,
     headers: headers,
     payload: payload,
     muteHttpExceptions: true

test/test.js

@@ -770,4 +770,31 @@ describe('Utilities', function() {
       assert.deepEqual(payload, {'foo': 'bar'});
     });
   });
+
+  describe('#setTokenMethod()', function() {
+    var decodeJwt_ = OAuth2.decodeJwt_;
+
+    it('should defautl to POST', function(done) {
+      mocks.UrlFetchApp.resultFunction = function(url, urlOptions) {
+        assert.equal(urlOptions.method, 'post');
+        done();
+      };
+      var service = OAuth2.createService('test')
+          .setGrantType('client_credentials')
+          .setTokenUrl('http://www.example.com')
+      service.exchangeGrant_();
+    });
+
+    it('should change the HTTP method used', function(done) {
+      mocks.UrlFetchApp.resultFunction = function(url, urlOptions) {
+        assert.equal(urlOptions.method, 'put');
+        done();
+      };
+      var service = OAuth2.createService('test')
+          .setGrantType('client_credentials')
+          .setTokenUrl('http://www.example.com')
+          .setTokenMethod('put');
+      service.exchangeGrant_();
+    });
+  });
 });