Isssue 3459 - Map the content type IMAGESET to IMAGE and FETCH to XMLHTTPREQUEST

lib/contentPolicy.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-2015 Eyeo GmbH
  *
  * Adblock Plus is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3 as
  * published by the Free Software Foundation.
  *
  * Adblock Plus is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 27 matching lines @@
 var Policy = exports.Policy =
 {
   /**
    * Set of explicitly supported content types
    * @type Set.<string>
    */
   contentTypes: new Set([
     "OTHER", "SCRIPT", "IMAGE", "STYLESHEET", "OBJECT", "SUBDOCUMENT", "DOCUMENT",
     "XMLHTTPREQUEST", "OBJECT_SUBREQUEST", "FONT", "MEDIA", "PING", "ELEMHIDE",
     "POPUP", "GENERICHIDE", "GENERICBLOCK"
   ]),

[Wladimir Palant, 2015/12/29 23:19:48]

This member becomes unnecessary with your change, it should be removed - the map
is all that's needed. IMHO, contentTypesMap should be renamed into contentTypes.
Initialization could go like this:

contentTypes: new Map([
  ["BEACON", "PING"],
  ...
].concat([
  // Everything else is mapped to itself
  "OTHER", "SCRIPT", ...
].map(x => [x, x])));

[Sebastian Noack, 2015/12/30 15:54:58]

Note that chrome/content/ui/sidebar.js and chrome/content/ui/composer.js use the
contentTypes property as well and expect a unique list of these content types.

[Wladimir Palant, 2016/01/06 12:46:00]

You are right but that's not a reason to duplicate the data structure. They can
rather use new Set(Policy.contentTypes.values()).

[Sebastian Noack, 2016/01/06 13:29:50]

There you go: https://codereview.adblockplus.org/29333254

 
   /**
+   * Map of content types reported by Firefox to the respecitve content types
+   * used by Adblock Plus. Other content types are simply mapped to OTHER.
+   * @type Map.<string,string>
+   */
+  contentTypesMap: new Map([
+    // Treat navigator.sendBeacon() the same as <a ping>,
+    // it's essentially the same concept - merely generalized.
+    ["BEACON", "PING"],
+
+    // Treat <img srcset> and <picture> the same as other images.
+    ["IMAGESET", "IMAGE"],
+
+    // Treat fetch() the same as XMLHttpRequest,
+    // it's essentially the same - merely a more modern API.
+    ["FETCH", "XMLHTTPREQUEST"]
+  ]),
+
+  /**
    * Set of content types that aren't associated with a visual document area
    * @type Set.<string>
    */
   nonVisualTypes: new Set([
     "SCRIPT", "STYLESHEET", "XMLHTTPREQUEST", "OBJECT_SUBREQUEST", "FONT",
     "PING", "ELEMHIDE", "POPUP", "GENERICHIDE", "GENERICBLOCK"
   ]),
 
   /**
    * Map containing all schemes that should be ignored by content policy.
    * @type Set.<string>
    */
   whitelistSchemes: new Set(),
 
   /**
    * Called on module startup, initializes various exported properties.
    */
   init: function()
   {
+    for (let contentType of this.contentTypes)
+      this.contentTypesMap.set(contentType, contentType);
+
     // whitelisted URL schemes
     for (let scheme of Prefs.whitelistschemes.toLowerCase().split(" "))
       this.whitelistSchemes.add(scheme);
 
     Utils.addChildMessageListener("AdblockPlus:ShouldAllow", message => this.shouldAllow(message));
 
     // Generate class identifier used to collapse nodes and register
     // corresponding stylesheet.
     let collapsedClass = "";
     let offset = "a".charCodeAt(0);
@@ skipping 38 matching lines @@
 
     function response(allow, collapse)
     {
       return {allow, collapse, hits};
     }
 
     // Ignore whitelisted schemes
     if (!this.isBlockableScheme(location))
       return response(true, false);
 
-    // Treat navigator.sendBeacon() the same as <a ping>, it's essentially the
-    // same concept - merely generalized.
-    if (contentType == "BEACON")
-      contentType = "PING";
-
     // Interpret unknown types as "other"
-    if (!this.contentTypes.has(contentType))
-      contentType = "OTHER";
+    contentType = this.contentTypesMap.get(contentType) || "OTHER";
 
     let wndLocation = frames[0].location;
     let docDomain = getHostname(wndLocation);
     let match = null;
     let [sitekey, sitekeyFrame] = getSitekey(frames);
     let nogeneric = false;
     if (!match && Prefs.enabled)
     {
       let testSitekey = sitekey;
       let testSitekeyFrame = sitekeyFrame;
@@ skipping 254 matching lines @@
   {
     // EffectiveTLDService throws on IP addresses, just compare the host name
     let host = "";
     try
     {
       host = uri.host;
     } catch (e) {}
     return host != docDomain;
   }
 }