feat(http): automatically set request Content-Type header based on body type

Implement the ability to provide objects as request body. The following use cases
are supported:
* raw objects: a JSON payload is created and the content type set to `application/json`
* text: the text is used as it is and no content type header is automatically added
* URLSearchParams: a form payload is created and the content type set to `application/x-www-form-urlencoded`
* FormData: the object is used as it is and no content type header is automatically added
* Blob: the object is used as it is and the content type set with the value of its `type` property if any
* ArrayBuffer: the object is used as it is and no content type header is automatically added

Closes https://github.com/angular/http/issues/69

Closes #7310

modules/@angular/core/src/reflection/reflection.ts

@@ -7,3 +7,4 @@ import {ReflectionCapabilities} from './reflection_capabilities';
  * about symbols.
  */
 export var reflector = new Reflector(new ReflectionCapabilities());
+

modules/@angular/http/src/backends/xhr_backend.ts

@@ -10,6 +10,7 @@ import {isPresent, isString} from '../../src/facade/lang';
 import {Observable} from 'rxjs/Observable';
 import {Observer} from 'rxjs/Observer';
 import {isSuccess, getResponseURL} from '../http_utils';
+import {ContentType} from '../enums';
 
 const XSSI_PREFIX = ')]}\',\n';
 
@@ -83,6 +84,8 @@ export class XHRConnection implements Connection {
         responseObserver.error(new Response(responseOptions));
       };
 
+      this.setDetectedContentType(req, _xhr);
+
       if (isPresent(req.headers)) {
         req.headers.forEach((values, name) => _xhr.setRequestHeader(name, values.join(',')));
       }
@@ -90,7 +93,7 @@ export class XHRConnection implements Connection {
       _xhr.addEventListener('load', onLoad);
       _xhr.addEventListener('error', onError);
 
-      _xhr.send(this.request.text());
+      _xhr.send(this.request.getBody());
 
       return () => {
         _xhr.removeEventListener('load', onLoad);
@@ -99,6 +102,34 @@ export class XHRConnection implements Connection {
       };
     });
   }
+
+  setDetectedContentType(req, _xhr) {
+    // Skip if a custom Content-Type header is provided
+    if (isPresent(req.headers) && isPresent(req.headers['Content-Type'])) {
+      return;
+    }
+
+    // Set the detected content type
+    switch (req.contentType) {
+      case ContentType.NONE:
+        break;
+      case ContentType.JSON:
+        _xhr.setRequestHeader('Content-Type', 'application/json');
+        break;
+      case ContentType.FORM:
+        _xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded;charset=UTF-8');
+        break;
+      case ContentType.TEXT:
+        _xhr.setRequestHeader('Content-Type', 'text/plain');
+        break;
+      case ContentType.BLOB:
+        var blob = req.blob();
+        if (blob.type) {
+          _xhr.setRequestHeader('Content-Type', blob.type);
+        }
+        break;
+    }
+  }
 }
 
 /**

modules/@angular/http/src/base_request_options.ts

@@ -43,8 +43,7 @@ export class RequestOptions {
   /**
    * Body to be used when creating a {@link Request}.
    */
-  // TODO: support FormData, Blob, URLSearchParams
+  body: any;
-  body: string;
   /**
    * Url with which to perform a {@link Request}.
    */

modules/@angular/http/src/enums.ts

@@ -36,3 +36,16 @@ export enum ResponseType {
   Error,
   Opaque
 }
+
+/**
+ * Supported content type to be automatically associated with a {@link Request}.
+ */
+export enum ContentType {
+  NONE,
+  JSON,
+  FORM,
+  FORM_DATA,
+  TEXT,
+  BLOB,
+  ARRAY_BUFFER
+}

modules/@angular/http/src/http.ts

@@ -5,6 +5,7 @@ import {RequestOptionsArgs, ConnectionBackend} from './interfaces';
 import {Request} from './static_request';
 import {Response} from './static_response';
 import {BaseRequestOptions, RequestOptions} from './base_request_options';
+import {URLSearchParams} from './url_search_params';
 import {RequestMethod} from './enums';
 import {Observable} from 'rxjs/Observable';
 
@@ -126,7 +127,7 @@ export class Http {
   /**
    * Performs a request with `post` http method.
    */
-  post(url: string, body: string, options?: RequestOptionsArgs): Observable<Response> {
+  post(url: string, body: any, options?: RequestOptionsArgs): Observable<Response> {
     return httpRequest(
         this._backend,
         new Request(mergeOptions(this._defaultOptions.merge(new RequestOptions({body: body})),
@@ -136,7 +137,7 @@ export class Http {
   /**
    * Performs a request with `put` http method.
    */
-  put(url: string, body: string, options?: RequestOptionsArgs): Observable<Response> {
+  put(url: string, body: any, options?: RequestOptionsArgs): Observable<Response> {
     return httpRequest(
         this._backend,
         new Request(mergeOptions(this._defaultOptions.merge(new RequestOptions({body: body})),
@@ -154,7 +155,7 @@ export class Http {
   /**
    * Performs a request with `patch` http method.
    */
-  patch(url: string, body: string, options?: RequestOptionsArgs): Observable<Response> {
+  patch(url: string, body: any, options?: RequestOptionsArgs): Observable<Response> {
     return httpRequest(
         this._backend,
         new Request(mergeOptions(this._defaultOptions.merge(new RequestOptions({body: body})),

modules/@angular/http/src/interfaces.ts

@@ -29,8 +29,7 @@ export interface RequestOptionsArgs {
   method?: string | RequestMethod;
   search?: string | URLSearchParams;
   headers?: Headers;
-  // TODO: Support Blob, ArrayBuffer, JSON, URLSearchParams, FormData
+  body?: any;
-  body?: string;
 }
 
 /**

modules/@angular/http/src/static_request.ts

@@ -1,6 +1,8 @@
 import {RequestMethod} from './enums';
 import {RequestArgs} from './interfaces';
 import {Headers} from './headers';
+import {ContentType} from './enums';
+import {URLSearchParams} from './url_search_params';
 import {normalizeMethodName} from './http_utils';
 import {isPresent, StringWrapper} from '../src/facade/lang';
 
@@ -53,8 +55,10 @@ export class Request {
   headers: Headers;
   /** Url of the remote resource */
   url: string;
-  // TODO: support URLSearchParams | FormData | Blob | ArrayBuffer
+  /** Body of the request **/
-  private _body: string;
+  private _body: any;
+  /** Type of the request body **/
+  private contentType: ContentType;
   constructor(requestOptions: RequestArgs) {
     // TODO: assert that url is present
     let url = requestOptions.url;
@@ -71,6 +75,7 @@ export class Request {
       }
     }
     this._body = requestOptions.body;
+    this.contentType = this.detectContentType();
     this.method = normalizeMethodName(requestOptions.method);
     // TODO(jeffbcross): implement behavior
     // Defaults to 'omit', consistent with browser
@@ -85,4 +90,82 @@ export class Request {
    * string.
    */
   text(): string { return isPresent(this._body) ? this._body.toString() : ''; }
+
+  /**
+   * Returns the request's body as JSON string, assuming that body exists. If body is undefined,
+   * return
+   * empty
+   * string.
+   */
+  json(): string { return isPresent(this._body) ? JSON.stringify(this._body) : ''; }
+
+  /**
+   * Returns the request's body as array buffer, assuming that body exists. If body is undefined,
+   * return
+   * null.
+   */
+  arrayBuffer(): ArrayBuffer {
+    if (this._body instanceof ArrayBuffer) return <ArrayBuffer>this._body;
+    throw "The request body isn't an array buffer";
+  }
+
+  /**
+   * Returns the request's body as blob, assuming that body exists. If body is undefined, return
+   * null.
+   */
+  blob(): Blob {
+    if (this._body instanceof Blob) return <Blob>this._body;
+    if (this._body instanceof ArrayBuffer) return new Blob([this._body]);
+    throw "The request body isn't either a blob or an array buffer";
+  }
+
+  /**
+   * Returns the content type of request's body based on its type.
+   */
+  detectContentType() {
+    if (this._body == null) {
+      return ContentType.NONE;
+    } else if (this._body instanceof URLSearchParams) {
+      return ContentType.FORM;
+    } else if (this._body instanceof FormData) {
+      return ContentType.FORM_DATA;
+    } else if (this._body instanceof Blob) {
+      return ContentType.BLOB;
+    } else if (this._body instanceof ArrayBuffer) {
+      return ContentType.ARRAY_BUFFER;
+    } else if (this._body && typeof this._body == 'object') {
+      return ContentType.JSON;
+    } else {
+      return ContentType.TEXT;
+    }
+  }
+
+  /**
+   * Returns the request's body according to its type. If body is undefined, return
+   * null.
+   */
+  getBody(): any {
+    switch (this.contentType) {
+      case ContentType.JSON:
+        return this.json();
+      case ContentType.FORM:
+        return this.text();
+      case ContentType.FORM_DATA:
+        return this._body;
+      case ContentType.TEXT:
+        return this.text();
+      case ContentType.BLOB:
+        return this.blob();
+      case ContentType.ARRAY_BUFFER:
+        return this.arrayBuffer();
+      default:
+        return null;
+    }
+  }
 }
+
+const noop = function () {};
+const w = typeof window == 'object' ? window : noop;
+const FormData = w['FormData'] || noop;
+const Blob = w['Blob'] || noop;
+const ArrayBuffer = w['ArrayBuffer'] || noop;

modules/@angular/http/test/backends/xhr_backend_spec.ts

@@ -20,6 +20,7 @@ import {Map} from '../../src/facade/collection';
 import {RequestOptions, BaseRequestOptions} from '../../src/base_request_options';
 import {BaseResponseOptions, ResponseOptions} from '../../src/base_response_options';
 import {ResponseType} from '../../src/enums';
+import {URLSearchParams} from '../../src/url_search_params';
 
 var abortSpy: any;
 var sendSpy: any;
@@ -176,6 +177,129 @@ export function main() {
         expect(setRequestHeaderSpy).toHaveBeenCalledWith('X-Multi', 'a,b');
       });
 
+      it('should use object body and detect content type header to the request', () => {
+        var body = {test: 'val'};
+        var base = new BaseRequestOptions();
+        var connection = new XHRConnection(
+            new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+        connection.response.subscribe();
+        expect(sendSpy).toHaveBeenCalledWith(JSON.stringify(body));
+        expect(setRequestHeaderSpy).toHaveBeenCalledWith('Content-Type', 'application/json');
+      });
+
+      it('should use number body and detect content type header to the request', () => {
+        var body = 23;
+        var base = new BaseRequestOptions();
+        var connection = new XHRConnection(
+            new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+        connection.response.subscribe();
+        expect(sendSpy).toHaveBeenCalledWith('23');
+        expect(setRequestHeaderSpy).toHaveBeenCalledWith('Content-Type', 'text/plain');
+      });
+
+      it('should use string body and detect content type header to the request', () => {
+        var body = 'some string';
+        var base = new BaseRequestOptions();
+        var connection = new XHRConnection(
+            new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+        connection.response.subscribe();
+        expect(sendSpy).toHaveBeenCalledWith(body);
+        expect(setRequestHeaderSpy).toHaveBeenCalledWith('Content-Type', 'text/plain');
+      });
+
+      it('should use URLSearchParams body and detect content type header to the request', () => {
+        var body = new URLSearchParams();
+        body.set('test1', 'val1');
+        body.set('test2', 'val2');
+        var base = new BaseRequestOptions();
+        var connection = new XHRConnection(
+            new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+        connection.response.subscribe();
+        expect(sendSpy).toHaveBeenCalledWith('test1=val1&test2=val2');
+        expect(setRequestHeaderSpy)
+            .toHaveBeenCalledWith('Content-Type',
+                                  'application/x-www-form-urlencoded;charset=UTF-8');
+      });
+
+      if (global['Blob']) {
+        it('should use FormData body and detect content type header to the request', () => {
+          var body = new FormData();
+          body.append('test1', 'val1');
+          body.append('test2', 123456);
+          var blob = new Blob(['body { color: red; }'], {type: 'text/css'});
+          body.append("userfile", blob);
+          var base = new BaseRequestOptions();
+          var connection = new XHRConnection(
+              new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+          connection.response.subscribe();
+          expect(sendSpy).toHaveBeenCalledWith(body);
+          expect(setRequestHeaderSpy).not.toHaveBeenCalledWith();
+        });
+
+        it('should use blob body and detect content type header to the request', () => {
+          var body = new Blob(['body { color: red; }'], {type: 'text/css'});
+          var base = new BaseRequestOptions();
+          var connection = new XHRConnection(
+              new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+          connection.response.subscribe();
+          expect(sendSpy).toHaveBeenCalledWith(body);
+          expect(setRequestHeaderSpy).toHaveBeenCalledWith('Content-Type', 'text/css');
+        });
+
+        it('should use blob body without type to the request', () => {
+          var body = new Blob(['body { color: red; }']);
+          var base = new BaseRequestOptions();
+          var connection = new XHRConnection(
+              new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+          connection.response.subscribe();
+          expect(sendSpy).toHaveBeenCalledWith(body);
+          expect(setRequestHeaderSpy).not.toHaveBeenCalledWith();
+        });
+
+        it('should use blob body without type with custom content type header to the request', () => {
+          var headers = new Headers({'Content-Type': 'text/css'});
+          var body = new Blob(['body { color: red; }']);
+          var base = new BaseRequestOptions();
+          var connection = new XHRConnection(
+              new Request(base.merge(new RequestOptions({body: body, headers: headers}))),
+              new MockBrowserXHR());
+          connection.response.subscribe();
+          expect(sendSpy).toHaveBeenCalledWith(body);
+          expect(setRequestHeaderSpy).toHaveBeenCalledWith('Content-Type', 'text/css');
+        });
+
+        it('should use array buffer body to the request', () => {
+          var body = new ArrayBuffer(512);
+          var longInt8View = new Uint8Array(body);
+          for (var i = 0; i < longInt8View.length; i++) {
+            longInt8View[i] = i % 255;
+          }
+          var base = new BaseRequestOptions();
+          var connection = new XHRConnection(
+            new Request(base.merge(new RequestOptions({body: body}))), new MockBrowserXHR());
+          connection.response.subscribe();
+          expect(sendSpy).toHaveBeenCalledWith(body);
+          expect(setRequestHeaderSpy).not.toHaveBeenCalledWith();
+        });
+
+        it('should use array buffer body without type with custom content type header to the request',
+          () => {
+            var headers = new Headers({'Content-Type': 'text/css'});
+            var body = new ArrayBuffer(512);
+            var longInt8View = new Uint8Array(body);
+            for (var i = 0; i < longInt8View.length; i++) {
+              longInt8View[i] = i % 255;
+            }
+            var base = new BaseRequestOptions();
+            var connection = new XHRConnection(
+              new Request(base.merge(new RequestOptions({body: body, headers: headers}))),
+              new MockBrowserXHR());
+            connection.response.subscribe();
+            expect(sendSpy).toHaveBeenCalledWith(body);
+            expect(setRequestHeaderSpy).toHaveBeenCalledWith('Content-Type', 'text/css');
+          });
+      }
+
       it('should return the correct status code',
          inject([AsyncTestCompleter], (async: AsyncTestCompleter) => {
            var statusCode = 418;

modules/@angular/platform-browser/testing/browser_util.ts

@@ -50,6 +50,8 @@ export class BrowserDetection {
   }
 }
 
+BrowserDetection.setup();
+
 export function dispatchEvent(element, eventType): void {
   getDOM().dispatchEvent(element, getDOM().createEvent(eventType));
 }