feat(fetch): schedule macroTask when fetch

file-size-limit.json

@@ -3,7 +3,7 @@
     {
       "path": "dist/zone.min.js",
       "checkTarget": true,
-      "limit": 40144
+      "limit": 41500
     }
   ]
-}
+}

lib/browser/browser.ts

@@ -199,8 +199,15 @@ Zone.__load_patch('XHR', (global: any, Zone: ZoneType) => {
         });
 
     const XMLHTTPREQUEST_SOURCE = 'XMLHttpRequest.send';
-    const sendNative =
+    const fetchTaskScheduling = zoneSymbol('fetchTaskScheduling');
+    const sendNative: Function|null =
         patchMethod(XMLHttpRequestPrototype, 'send', () => function(self: any, args: any[]) {
+          if ((Zone.current as any)[fetchTaskScheduling]) {
+            // a fetch is scheduling, so we are using xhr to polyfill fetch
+            // and because we already schedule macroTask for fetch, we should
+            // not schedule a macroTask for xhr again
+            return sendNative!.apply(self, args);
+          }
           if (self[XHR_SYNC]) {
             // if the XHR is sync there is no task to schedule, just execute the code.
             return sendNative!.apply(self, args);

lib/browser/rollup-main.ts

@@ -8,5 +8,6 @@
 
 import '../zone';
 import '../common/promise';
+import '../common/fetch';
 import '../common/to-string';
 import './browser';

lib/common/fetch.ts

@@ -0,0 +1,94 @@
+/**
+ * @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
+ */
+
+Zone.__load_patch('fetch', (global: any, Zone: ZoneType, api: _ZonePrivate) => {
+  const fetch = global['fetch'];
+  const ZoneAwarePromise = global.Promise;
+  const symbolThenPatched = api.symbol('thenPatched');
+  const fetchTaskScheduling = api.symbol('fetchTaskScheduling');
+  if (typeof fetch !== 'function') {
+    return;
+  }
+  const OriginalAbortController = global['AbortController'];
+  const supportAbort = typeof OriginalAbortController === 'function';
+  let abortNative: Function|null = null;
+  if (supportAbort) {
+    global['AbortController'] = function() {
+      const abortController = new OriginalAbortController();
+      const signal = abortController.signal;
+      signal.abortController = abortController;
+      return abortController;
+    };
+    abortNative = api.patchMethod(
+        OriginalAbortController.prototype, 'abort',
+        (delegate: Function) => (self: any, args: any) => {
+          if (self.task) {
+            return self.task.zone.cancelTask(self.task);
+          }
+          return delegate.apply(self, args);
+        });
+  }
+  const placeholder = function() {};
+  global['fetch'] = function() {
+    const args = Array.prototype.slice.call(arguments);
+    const options = args.length > 1 ? args[1] : null;
+    const signal = options && options.signal;
+    return new Promise((res, rej) => {
+      const task = Zone.current.scheduleMacroTask(
+          'fetch', placeholder, args,
+          () => {
+            let fetchPromise;
+            let zone = Zone.current;
+            try {
+              (zone as any)[fetchTaskScheduling] = true;
+              fetchPromise = fetch.apply(this, args);
+            } catch (error) {
+              rej(error);
+              return;
+            } finally {
+              (zone as any)[fetchTaskScheduling] = false;
+            }
+
+            if (!(fetchPromise instanceof ZoneAwarePromise)) {
+              let ctor = fetchPromise.constructor;
+              if (!ctor[symbolThenPatched]) {
+                api.patchThen(ctor);
+              }
+            }
+            fetchPromise.then(
+                (resource: any) => {
+                  if (task.state !== 'notScheduled') {
+                    task.invoke();
+                  }
+                  res(resource);
+                },
+                (error: any) => {
+                  if (task.state !== 'notScheduled') {
+                    task.invoke();
+                  }
+                  rej(error);
+                });
+          },
+          () => {
+            if (!supportAbort) {
+              rej('No AbortController supported, can not cancel fetch');
+              return;
+            }
+            if (signal && signal.abortController && !signal.aborted &&
+                typeof signal.abortController.abort === 'function' && abortNative) {
+              abortNative.call(signal.abortController);
+            } else {
+              rej('cancel fetch need a AbortController.signal');
+            }
+          });
+      if (signal && signal.abortController) {
+        signal.abortController.task = task;
+      }
+    });
+  };
+});

lib/common/promise.ts

@@ -458,6 +458,8 @@ Zone.__load_patch('ZoneAwarePromise', (global: any, Zone: ZoneType, api: _ZonePr
     (Ctor as any)[symbolThenPatched] = true;
   }
 
+  api.patchThen = patchThen;
+
   function zoneify(fn: Function) {
     return function() {
       let resultPromise = fn.apply(this, arguments);
@@ -475,10 +477,10 @@ Zone.__load_patch('ZoneAwarePromise', (global: any, Zone: ZoneType, api: _ZonePr
   if (NativePromise) {
     patchThen(NativePromise);
 
-    let fetch = global['fetch'];
+    /*let fetch = global['fetch'];
     if (typeof fetch == 'function') {
       global['fetch'] = zoneify(fetch);
-    }
+    }*/
   }
 
   // This is not part of public API, but it is useful for tests, so we expose it.

lib/zone.ts

@@ -322,6 +322,7 @@ interface _ZonePrivate {
   showUncaughtError: () => boolean;
   patchEventTarget: (global: any, apis: any[], options?: any) => boolean[];
   patchOnProperties: (obj: any, properties: string[]|null) => void;
+  patchThen: (ctro: Function) => void;
   setNativePromise: (nativePromise: any) => void;
   patchMethod:
       (target: any, name: string,
@@ -1326,7 +1327,8 @@ const Zone: ZoneType = (function(global: any) {
     patchEventTarget: () => [],
     patchOnProperties: noop,
     patchMethod: () => noop,
-    bindArguments: () => (null as any),
+    bindArguments: () => [],
+    patchThen: () => noop,
     setNativePromise: (NativePromise: any) => {
       // sometimes NativePromise.resolve static function
       // is not ready yet, (such as core-js/es6.promise)

test/browser-zone-setup.ts

@@ -11,6 +11,7 @@ if (typeof window !== 'undefined') {
 }
 import '../lib/common/to-string';
 import '../lib/browser/browser';
+import '../lib/common/fetch';
 import '../lib/browser/webapis-user-media';
 import '../lib/browser/webapis-media-query';
 import '../lib/testing/zone-testing';

test/common/Promise.spec.ts

@@ -549,76 +549,4 @@ describe(
           testPromiseSubClass();
         });
       });
-
-      describe('fetch', ifEnvSupports('fetch', function() {
-                 it('should work for text response', function(done) {
-                   testZone.run(function() {
-                     global['fetch']('/base/test/assets/sample.json').then(function(response: any) {
-                       const fetchZone = Zone.current;
-                       expect(fetchZone).toBe(testZone);
-
-                       response.text().then(function(text: string) {
-                         expect(Zone.current).toBe(fetchZone);
-                         expect(text.trim()).toEqual('{"hello": "world"}');
-                         done();
-                       });
-                     });
-                   });
-                 });
-
-                 it('should work for json response', function(done) {
-                   testZone.run(function() {
-                     global['fetch']('/base/test/assets/sample.json').then(function(response: any) {
-                       const fetchZone = Zone.current;
-                       expect(fetchZone).toBe(testZone);
-
-                       response.json().then(function(obj: any) {
-                         expect(Zone.current).toBe(fetchZone);
-                         expect(obj.hello).toEqual('world');
-                         done();
-                       });
-                     });
-                   });
-                 });
-
-                 it('should work for blob response', function(done) {
-                   testZone.run(function() {
-                     global['fetch']('/base/test/assets/sample.json').then(function(response: any) {
-                       const fetchZone = Zone.current;
-                       expect(fetchZone).toBe(testZone);
-
-                       // Android 4.3- doesn't support response.blob()
-                       if (response.blob) {
-                         response.blob().then(function(blob: any) {
-                           expect(Zone.current).toBe(fetchZone);
-                           expect(blob instanceof Blob).toEqual(true);
-                           done();
-                         });
-                       } else {
-                         done();
-                       }
-                     });
-                   });
-                 });
-
-                 it('should work for arrayBuffer response', function(done) {
-                   testZone.run(function() {
-                     global['fetch']('/base/test/assets/sample.json').then(function(response: any) {
-                       const fetchZone = Zone.current;
-                       expect(fetchZone).toBe(testZone);
-
-                       // Android 4.3- doesn't support response.arrayBuffer()
-                       if (response.arrayBuffer) {
-                         response.arrayBuffer().then(function(blob: any) {
-                           expect(Zone.current).toBe(fetchZone);
-                           expect(blob instanceof ArrayBuffer).toEqual(true);
-                           done();
-                         });
-                       } else {
-                         done();
-                       }
-                     });
-                   });
-                 });
-               }));
     }));