Issue 537 - Mark first few downloads

lib/downloader.js

 /*
  * This file is part of Adblock Plus <http://adblockplus.org/>,
  * Copyright (C) 2006-2014 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 173 matching lines @@
    * parameters.
    */
   getDownloadUrl: function(/**Downloadable*/ downloadable)  /** String*/
   {
     let {addonName, addonVersion, application, applicationVersion, platform, platformVersion} = require("info");
     let url = downloadable.redirectURL || downloadable.url;
     if (url.indexOf("?") >= 0)
       url += "&";
     else
       url += "?";
+    // We limit the download count to 4+ to keep the request anonymized
+    let downloadCount = downloadable.downloadCount;
+    if (downloadCount > 4)
+      downloadCount = "4+";
     url += "addonName=" + encodeURIComponent(addonName) +
         "&addonVersion=" + encodeURIComponent(addonVersion) +
         "&application=" + encodeURIComponent(application) +
         "&applicationVersion=" + encodeURIComponent(applicationVersion) +
         "&platform=" + encodeURIComponent(platform) +
         "&platformVersion=" + encodeURIComponent(platformVersion) +
-        "&lastVersion=" + encodeURIComponent(downloadable.lastVersion);
+        "&lastVersion=" + encodeURIComponent(downloadable.lastVersion) +
+        "&downloadCount=" + encodeURIComponent(downloadCount);
     return url;
   },
 
   _download: function(downloadable, redirects)
   {
     if (this.isDownloading(downloadable.url))
       return;
 
     let downloadUrl = this.getDownloadUrl(downloadable);
     let request = null;
@@ skipping 73 matching lines @@
 
       delete this._downloading[downloadable.url];
 
       // Status will be 0 for non-HTTP requests
       if (request.status && request.status != 200)
       {
         errorCallback("synchronize_connection_error");
         return;
       }
 
+      downloadable.downloadCount++;
+
       this.onDownloadSuccess(downloadable, request.responseText, errorCallback, function redirectCallback(url)
       {
         if (redirects >= this.maxRedirects)
           errorCallback("synchronize_connection_error");
         else
         {
           downloadable.redirectURL = url;
           this._download(downloadable, redirects + 1);
         }
       }.bind(this));
@@ skipping 67 matching lines @@
    * while.
    * @type Integer
    */
   softExpiration: 0,
 
   /**
    * Hard expiration interval, this is fixed.
    * @type Integer
    */
   hardExpiration: 0,
+  
+  /**
+   * Number indicating how often the object was downloaded.
+   * @type Integer
+   */
+  downloadCount: 0,
 };