refactor(http): share 'body' logic between Request and Response

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

@@ -0,0 +1,84 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {Json, isString} from '../src/facade/lang';
+
+import {isJsObject, stringToArrayBuffer} from './http_utils';
+import {URLSearchParams} from './url_search_params';
+
+
+/**
+ * HTTP request body used by both {@link Request} and {@link Response}
+ * https://fetch.spec.whatwg.org/#body
+ */
+export abstract class Body {
+  /**
+   * @internal
+   */
+  protected _body: any;
+
+  /**
+   * Attempts to return body as parsed `JSON` object, or raises an exception.
+   */
+  json(): any {
+    if (isString(this._body)) {
+      return Json.parse(<string>this._body);
+    }
+
+    if (this._body instanceof ArrayBuffer) {
+      return Json.parse(this.text());
+    }
+
+    return this._body;
+  }
+
+  /**
+   * Returns the body as a string, presuming `toString()` can be called on the response body.
+   */
+  text(): string {
+    if (this._body instanceof URLSearchParams) {
+      return this._body.toString();
+    }
+
+    if (this._body instanceof ArrayBuffer) {
+      return String.fromCharCode.apply(null, new Uint16Array(<ArrayBuffer>this._body));
+    }
+
+    if (isJsObject(this._body)) {
+      return Json.stringify(this._body);
+    }
+
+    return this._body.toString();
+  }
+
+  /**
+   * Return the body as an ArrayBuffer
+   */
+  arrayBuffer(): ArrayBuffer {
+    if (this._body instanceof ArrayBuffer) {
+      return <ArrayBuffer>this._body;
+    }
+
+    return stringToArrayBuffer(this.text());
+  }
+
+  /**
+    * Returns the request's body as a Blob, assuming that body exists.
+    */
+  blob(): Blob {
+    if (this._body instanceof Blob) {
+      return <Blob>this._body;
+    }
+
+    if (this._body instanceof ArrayBuffer) {
+      return new Blob([this._body]);
+    }
+
+    throw new Error('The request body isn\'t either a blob or an array buffer');
+  }
+}