this fixes #97

Author: gorhill

css/popup.css

@@ -237,7 +237,7 @@ body #scopeKeys {
     text-align: right;
     }
 .matrix .matRow.l2 > .matCell:first-child {
-    direction: rtl;
+    /* direction: rtl; */
     }
 .matrix .matRow > .matCell:hover {
     border-style: solid;

info.html

@@ -78,6 +78,7 @@ <h2 id="generic-stats">Generic stats</h2>
 <li><a href="https://en.wikipedia.org/wiki/HTTP_referer">HTTP referer</a> headers foiled: <span id="refererHeaderFoiledCounter"></span>
 <li>Local cookies removed: <span id="cookieRemovedCounter"></span>
 <li><a href="http://diveintohtml5.info/storage.html">Local storages</a> emptied: <span id="localStorageRemovedCounter"></span>
+<li>Browser caches cleared: <span id="browserCacheClearedCounter"></span>
 </ul>
 </div>
 

js/async.js

@@ -61,19 +61,21 @@ var asyncJobQueue = {
 
     _process: function() {
         var now = Date.now();
-        var keys = Object.keys(this.jobs);
-        var i = keys.length;
+        var jobs = this.jobs;
         var job;
-        while ( i-- ) {
-            job = this.jobs[keys[i]];
+        for ( var jobName in jobs ) {
+            if ( !jobs.hasOwnProperty(jobName) ) {
+                continue;
+            }
+            job = jobs[jobName];
             if ( job.when > now ) {
                 continue;
             }
             job.callback(job.data);
             if ( job.period ) {
-                job.when = Date.now() + job.period;
+                job.when = now + job.period;
             } else {
-                delete this.jobs[job.name];
+                delete jobs[jobName];
                 job._nullify();
                 this.jobCount--;
                 this.junkyard.push(job);
@@ -83,12 +85,10 @@ var asyncJobQueue = {
 };
 
 function asyncJobQueueHandler() {
-    if ( asyncJobQueue.jobCount ) {
-        asyncJobQueue._process();
-    }
+    asyncJobQueue._process();
 }
 
-setInterval(asyncJobQueueHandler, 100);
+setInterval(asyncJobQueueHandler, asyncJobQueue.resolution);
 
 /******************************************************************************/
 

js/background.js

@@ -38,12 +38,13 @@ var HTTPSB = {
         popupCollapseDomains: false,
         popupCollapseSpecificDomains: {},
         maxLoggedRequests: 50,
-        statsFilters: {
-        }
+        statsFilters: {},
+        clearBrowserCache: false,
+        clearBrowserCacheAfter: 60
     },
 
     runtimeId: 1,
-
+    clearBrowserCacheCycle: 0,
     inlineFieldSeparator: '#',
 
     // list of remote blacklist locations
@@ -90,11 +91,12 @@ var HTTPSB = {
     localStorageRemovedCounter: 0,
     cookieHeaderFoiledCounter: 0,
     refererHeaderFoiledCounter: 0,
+    browserCacheClearedCounter: 0,
 
     // internal state
     webRequestHandler: false,
 
-    // record what chromium is soing behind the scene
+    // record what chromium is doing behind the scene
     behindTheSceneURL: 'http://chromium.behind.the.scene',
     behindTheSceneTabId: 0x7FFFFFFF,
     behindTheSceneMaxReq: 250,

js/info.js

@@ -174,6 +174,7 @@ function renderStats() {
         '#localStorageRemovedCounter': httpsb.localStorageRemovedCounter,
         '#cookieHeaderFoiledCounter': httpsb.cookieHeaderFoiledCounter,
         '#refererHeaderFoiledCounter': httpsb.refererHeaderFoiledCounter,
+        '#browserCacheClearedCounter': httpsb.browserCacheClearedCounter,
         '#blockedAllCount': requestStats.blocked.all,
         '#blockedMainFrameCount': blockedStats.main_frame,
         '#blockedCookieCount': blockedStats.cookie,

js/settings.js

@@ -182,6 +182,8 @@ function initAll() {
     $('#delete-unused-session-cookies-after').val(userSettings.deleteUnusedSessionCookiesAfter);
     $('#delete-blacklisted-cookies').attr('checked', userSettings.deleteCookies === true);
     $('#delete-blacklisted-localstorage').attr('checked', userSettings.deleteLocalStorage);
+    $('#clear-browser-cache').attr('checked', userSettings.clearBrowserCache === true);
+    $('#clear-browser-cache-after').val(userSettings.clearBrowserCacheAfter);
     $('#process-referer').attr('checked', userSettings.processReferer);
     $('#process-behind-the-scene').attr('checked', userSettings.processBehindTheSceneRequests);
     $('#max-logged-requests').val(userSettings.maxLoggedRequests);
@@ -211,6 +213,12 @@ function initAll() {
     $('#delete-blacklisted-localstorage').on('change', function(){
         changeUserSettings('deleteLocalStorage', $(this).is(':checked'));
     });
+    $('#clear-browser-cache').on('change', function(){
+        changeUserSettings('clearBrowserCache', $(this).is(':checked'));
+    });
+    $('#clear-browser-cache-after').on('change', function(){
+        onChangeValueHandler($(this), 'clearBrowserCacheAfter', 15, 1440);
+    });
     $('#process-referer').on('change', function(){
         changeUserSettings('processReferer', $(this).is(':checked'));
     });

js/start.js

@@ -157,3 +157,22 @@ function onDisconnectHandler() {
 
 chrome.extension.onConnect.addListener(onConnectHandler);
 
+/******************************************************************************/
+
+// Browser data jobs
+
+function clearBrowserCacheCallback() {
+    var httpsb = HTTPSB;
+
+    if ( httpsb.userSettings.clearBrowserCache ) {
+        httpsb.clearBrowserCacheCycle -= 15;
+        if ( httpsb.clearBrowserCacheCycle <= 0 ) {
+            httpsb.clearBrowserCacheCycle = httpsb.userSettings.clearBrowserCacheAfter;
+            httpsb.browserCacheClearedCounter++;
+            chrome.browsingData.removeCache({ since: 0 });
+        }
+    }
+}
+
+asyncJobQueue.add('clearBrowserCache', null, clearBrowserCacheCallback, 15 * 60 * 1000, true);
+

manifest.json

@@ -1,7 +1,7 @@
 {
     "manifest_version": 2,
     "name": "__MSG_extName__",
-    "version": "0.7.3.1",
+    "version": "0.7.4.0",
     "description": "__MSG_extShortDesc__",
     "icons": {
         "16": "icon_16.png",
@@ -29,6 +29,7 @@
     "default_locale": "en",
     "options_page": "settings.html",
     "permissions": [
+        "browsingData",
         "contentSettings",
         "contextMenus",
         "cookies",

settings.html

@@ -148,11 +148,29 @@ <h2>Privacy</h2>
             having to close the browser in order for the session cookies to clear might not
             be early enough.</p>
             </div>
-        <li>&nbsp;
         <li>
             <input id="delete-blacklisted-localstorage" type="checkbox" value="">Delete contents of
             <a href="http://en.wikipedia.org/wiki/Web_storage">local storage</a> of blocked hostnames
-        <li>&nbsp;
+        <li>
+            <input id="clear-browser-cache" type="checkbox" value="">Clear browser cache every
+            <input id="clear-browser-cache-after" type="text" value="60" size="3">minutes.
+            <button class="whatisthis"></button>
+            <div class="expandable">
+            <p>Some web sites are really bent on tracking you, so much that they will use
+            not-so-nice tricks to work around whatever measures you take in order to not be tracked.</p>
+            <p>A few of these tricks rely<sup style="font-size:smaller">[1, 2]</sup> on the <a href="https://en.wikipedia.org/wiki/Web_cache">browser cache</a>,
+            which content is often long lasting since rarely will users take the time to
+            regularly clear their browser cache.</p>
+            <p>There is little inconvenience to clear the browser cache regularly
+            (likelihood is that you won't notice when it happens), and the benefit
+            is to prevent these obnoxious trackers from invading your privacy.</p>
+            <p>Check this option to have <i>HTTP Switchboard</i> do it for you, at the interval you
+            wish.</p>
+            <p style="font-size:smaller">
+            [1] <a href="https://grepular.com/Preventing_Web_Tracking_via_the_Browser_Cache">&ldquo;Preventing Web Tracking via the Browser Cache&rdquo;</a><br>
+            [2] <a href="http://lucb1e.com/rp/cookielesscookies/">&ldquo;Cookieless cookies&rdquo;</a>
+            </p>
+            </div>
         <li>
             <input id="process-referer" type="checkbox" value="">Remove third-party 
             <a href="https://en.wikipedia.org/wiki/HTTP_referer">HTTP referer</a> information