Cancel requests received before Badger is ready

Once Badged is finished initializing, reload any tabs with cancelled
requests.

Author: ghostwords

src/js/background.js

@@ -34,10 +34,19 @@ var incognito = require("incognito");
 
 /**
  * Privacy Badger initializer.
+ *
+ * @param {Boolean} from_qunit don't intercept requests when run by unit tests
  */
-function Badger() {
+function Badger(from_qunit) {
   let self = this;
 
+  // important: must be executed synchronously
+  // to register a "persistent" onBeforeRequest listener in Firefox
+  // https://github.com/mdn/sprints/issues/1015
+  if (!from_qunit) {
+    webrequest.startBeforeReadyListener();
+  }
+
   self.webRTCAvailable = checkWebRTCBrowserSupport();
   self.firstPartyDomainPotentiallyRequired = testCookiesFirstPartyDomain();
 
@@ -81,13 +90,20 @@ function Badger() {
     await dntHashesPromise;
     await tabDataPromise;
 
+    if (from_qunit) {
+      self.INITIALIZED = true;
+      return;
+    }
+
     // start the listeners
     incognito.startListeners();
     webrequest.startListeners();
     HeuristicBlocking.startListeners();
     FirefoxAndroid.startListeners();
     startBackgroundListeners();
 
+    webrequest.stopBeforeReadyListener();
+
     console.log("Privacy Badger is ready to rock!");
     console.log("Set DEBUG=1 to view console messages.");
     self.INITIALIZED = true;
@@ -987,4 +1003,4 @@ function startBackgroundListeners() {
   });
 }
 
-var badger = window.badger = new Badger();
+let badger = window.badger = new Badger(document.location.pathname == "/tests/index.html");

src/js/webrequest.js

@@ -34,7 +34,8 @@ var incognito = require("incognito");
 var utils = require("utils");
 
 /************ Local Variables *****************/
-var temporaryWidgetUnblock = {};
+let temporaryWidgetUnblock = {};
+let pendingTabs = new Set();
 
 /***************** Blocking Listener Functions **************/
 
@@ -1059,17 +1060,57 @@ function dispatcher(request, sender, sendResponse) {
   }
 }
 
+
+/**
+ * Cancels all requests, populates list of pending tabs to be reloaded later,
+ * when Privacy Badger is ready.
+ *
+ * @param {Object} details chrome.webRequest request details
+ * @returns {Object}
+ */
+function onBeforeReady(details) {
+  if (!pendingTabs || details.tabId < 0) {
+    return;
+  }
+
+  pendingTabs.add(details.tabId);
+
+  return {
+    cancel: true
+  };
+}
+
+/**
+ * Reloads all tabs that loaded before Privacy Badger was ready.
+ */
+function reloadPendingTabs() {
+  for (let tab_id of pendingTabs) {
+    chrome.tabs.reload(tab_id);
+  }
+  pendingTabs = null;
+}
+
+
 /*************** Event Listeners *********************/
+function startBeforeReadyListener() {
+  chrome.webRequest.onBeforeRequest.addListener(onBeforeReady, {urls: ["<all_urls>"]}, ["blocking"]);
+}
+
+function stopBeforeReadyListener() {
+  chrome.webRequest.onBeforeRequest.removeListener(onBeforeReady);
+  reloadPendingTabs();
+}
+
 function startListeners() {
   chrome.webNavigation.onBeforeNavigate.addListener(onNavigate);
 
-  chrome.webRequest.onBeforeRequest.addListener(onBeforeRequest, {urls: ["http://*/*", "https://*/*"]}, ["blocking"]);
+  chrome.webRequest.onBeforeRequest.addListener(onBeforeRequest, {urls: ["<all_urls>"]}, ["blocking"]);
 
   let extraInfoSpec = ['requestHeaders', 'blocking'];
   if (chrome.webRequest.OnBeforeSendHeadersOptions.hasOwnProperty('EXTRA_HEADERS')) {
     extraInfoSpec.push('extraHeaders');
   }
-  chrome.webRequest.onBeforeSendHeaders.addListener(onBeforeSendHeaders, {urls: ["http://*/*", "https://*/*"]}, extraInfoSpec);
+  chrome.webRequest.onBeforeSendHeaders.addListener(onBeforeSendHeaders, {urls: ["<all_urls>"]}, extraInfoSpec);
 
   extraInfoSpec = ['responseHeaders', 'blocking'];
   if (chrome.webRequest.OnHeadersReceivedOptions.hasOwnProperty('EXTRA_HEADERS')) {
@@ -1083,8 +1124,11 @@ function startListeners() {
 }
 
 /************************************** exports */
-var exports = {};
-exports.startListeners = startListeners;
+let exports = {
+  startBeforeReadyListener,
+  startListeners,
+  stopBeforeReadyListener,
+};
 return exports;
 /************************************** exports */
 })();

tests/selenium/pbtest.py

@@ -320,8 +320,10 @@ def run(self, result=None):
                     # wait for Badger's storage, listeners, ...
                     self.load_url(self.options_url)
                     self.wait_for_script(
-                        "return chrome.extension.getBackgroundPage()."
-                        "badger.INITIALIZED"
+                        "return ("
+                        "  chrome.extension &&"
+                        "  chrome.extension.getBackgroundPage().badger.INITIALIZED"
+                        ");"
                     )
                     driver.close()
                     if driver.window_handles: