puppeteer · ebidel · Dec 14, 2017 · Dec 14, 2017 · Dec 16, 2017 · Dec 16, 2017
diff --git a/docs/api.md b/docs/api.md
@@ -187,6 +187,8 @@
   * [request.url()](#requesturl)
 - [class: Response](#class-response)
   * [response.buffer()](#responsebuffer)
+  * [response.fromCache()](#responsefromcache)
+  * [response.fromServiceWorker()](#responsefromserviceworker)
   * [response.headers()](#responseheaders)
   * [response.json()](#responsejson)
   * [response.ok()](#responseok)
@@ -2111,6 +2113,16 @@ page.on('request', request => {
 #### response.buffer()
 - returns: <Promise<[Buffer]>> Promise which resolves to a buffer with response body.
 
+#### response.fromCache()
+- returns: <[boolean]>
+
+True if the response was served from either the browser's disk cache or memory cache.
+
+#### response.fromServiceWorker()
+- returns: <[boolean]>
+
+True if the response was served by a service worker.
+
 #### response.headers()
 - returns: <[Object]> An object with HTTP headers associated with the response. All header names are lower-case.
 

diff --git a/lib/NetworkManager.js b/lib/NetworkManager.js
@@ -46,6 +46,7 @@ class NetworkManager extends EventEmitter {
 
     this._client.on('Network.requestWillBeSent', this._onRequestWillBeSent.bind(this));
     this._client.on('Network.requestIntercepted', this._onRequestIntercepted.bind(this));
+    this._client.on('Network.requestServedFromCache', this._onRequestServedFromCache.bind(this));
     this._client.on('Network.responseReceived', this._onResponseReceived.bind(this));
     this._client.on('Network.loadingFinished', this._onLoadingFinished.bind(this));
     this._client.on('Network.loadingFailed', this._onLoadingFailed.bind(this));
@@ -165,6 +166,15 @@ class NetworkManager extends EventEmitter {
     }
   }
 
+  /**
+   * @param {!Object} event
+   */
+  _onRequestServedFromCache(event) {
+    const request = this._requestIdToRequest.get(event.requestId);
+    if (request)
+      request._fromMemoryCache = true;
+  }
+
   /**
    * @param {!Request} request
    * @param {number} redirectStatus
@@ -233,7 +243,8 @@ class NetworkManager extends EventEmitter {
     // FileUpload sends a response without a matching request.
     if (!request)
       return;
-    const response = new Response(this._client, request, event.response.status, event.response.headers);
+    const response = new Response(this._client, request, event.response.status, event.response.headers,
+        event.response.fromDiskCache, event.response.fromServiceWorker);
     request._response = response;
     this.emit(NetworkManager.Events.Response, response);
   }
@@ -301,6 +312,8 @@ class Request {
     this._headers = {};
     for (const key of Object.keys(payload.headers))
       this._headers[key.toLowerCase()] = payload.headers[key];
+
+    this._fromMemoryCache = false;
   }
 
   /**
@@ -467,14 +480,18 @@ class Response {
    * @param {!Request} request
    * @param {number} status
    * @param {!Object} headers
+   * @param {boolean=} fromDiskCache True when the response was served from the disk cache.
+   * @param {boolean=} fromServiceWorker True when the response claim from a service worker.
    */
-  constructor(client, request, status, headers) {
+  constructor(client, request, status, headers, fromDiskCache = false, fromServiceWorker = false) {
     this._client = client;
     this._request = request;
     this._contentPromise = null;
 
     this._status = status;
     this._url = request.url();
+    this._fromDiskCache = fromDiskCache;
+    this._fromServiceWorker = fromServiceWorker;
     this._headers = {};
     for (const key of Object.keys(headers))
       this._headers[key.toLowerCase()] = headers[key];
@@ -545,6 +562,20 @@ class Response {
   request() {
     return this._request;
   }
+
+  /**
+   * @return {boolean}
+   */
+  fromCache() {
+    return this._fromDiskCache || this._request._fromMemoryCache;
+  }
+
+  /**
+   * @return {boolean}
+   */
+  fromServiceWorker() {
+    return this._fromServiceWorker;
+  }
 }
 helper.tracePublicAPI(Response);
 

diff --git a/test/assets/sw-fetch.html b/test/assets/sw-fetch.html
@@ -0,0 +1,4 @@
+<link rel="stylesheet" href="./one-style.css">
+<script>
+  navigator.serviceWorker.register('sw-fetch.js');
+</script>
diff --git a/test/assets/sw-fetch.js b/test/assets/sw-fetch.js
@@ -0,0 +1,3 @@
+self.addEventListener('fetch', event => {
+  event.respondWith(fetch(event.request));
+});
diff --git a/test/test.js b/test/test.js
@@ -2497,6 +2497,8 @@ describe('Page', function() {
       expect(responses[0].url()).toBe(server.EMPTY_PAGE);
       expect(responses[0].status()).toBe(200);
       expect(responses[0].ok()).toBe(true);
+      expect(responses[0].fromCache()).toBe(false);
+      expect(responses[0].fromServiceWorker()).toBe(false);
       expect(responses[0].request()).toBeTruthy();
     });
     it('Page.Events.Response should provide body', async({page, server}) => {
@@ -3578,6 +3580,25 @@ describe('Page', function() {
       });
     });
   });
+
+  describe('Response', function() {
+    it('specifies when response comes from cache and service worker', async({page, server}) => {
+      let responses = [];
+      page.on('response', response => {
+        if (response.url().includes('.css'))
+          responses.push(response);
+      });
+
+      await page.goto(server.PREFIX + '/sw-fetch.html', {waitUntil: 'networkidle2'});
+      expect(responses[0].fromCache()).toBe(false);
+      expect(responses[0].fromServiceWorker()).toBe(false);
+
+      responses = [];
+      await page.reload({waitUntil: 'networkidle2'});
+      expect(responses[0].fromCache()).toBe(true);
+      expect(responses[0].fromServiceWorker()).toBe(true);
+    });
+  });
 });
 
 if (process.env.COVERAGE) {