Issue 2595 - Use the core code from adblockpluscore

lib/downloader.js

Index: lib/downloader.js
===================================================================
deleted file mode 100644
--- a/lib/downloader.js
+++ /dev/null
@@ -1,394 +0,0 @@
-/*
- * This file is part of Adblock Plus <https://adblockplus.org/>,
- * Copyright (C) 2006-2016 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
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-/**
- * @fileOverview Downloads a set of URLs in regular time intervals.
- */
-
-let {Utils} = require("utils");
-
-let MILLIS_IN_SECOND = exports.MILLIS_IN_SECOND = 1000;
-let MILLIS_IN_MINUTE = exports.MILLIS_IN_MINUTE = 60 * MILLIS_IN_SECOND;
-let MILLIS_IN_HOUR = exports.MILLIS_IN_HOUR = 60 * MILLIS_IN_MINUTE;
-let MILLIS_IN_DAY = exports.MILLIS_IN_DAY = 24 * MILLIS_IN_HOUR;
-
-/**
- * Creates a new downloader instance.
- * @param {Function} dataSource  Function that will yield downloadable objects on each check
- * @param {Integer} initialDelay  Number of milliseconds to wait before the first check
- * @param {Integer} checkInterval  Interval between the checks
- * @constructor
- */
-let Downloader = exports.Downloader = function Downloader(dataSource, initialDelay, checkInterval)
-{
-  this.dataSource = dataSource;
-  this._timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
-  this._timer.initWithCallback(function()
-  {
-    this._timer.delay = checkInterval;
-    this._doCheck();
-  }.bind(this), initialDelay, Ci.nsITimer.TYPE_REPEATING_SLACK);
-  this._downloading = Object.create(null);
-}
-Downloader.prototype =
-{
-  /**
-   * Timer triggering the downloads.
-   * @type nsITimer
-   */
-  _timer: null,
-
-  /**
-   * Map containing the URLs of objects currently being downloaded as its keys.
-   */
-  _downloading: null,
-
-  /**
-   * Function that will yield downloadable objects on each check.
-   * @type Function
-   */
-  dataSource: null,
-
-  /**
-   * Maximal time interval that the checks can be left out until the soft
-   * expiration interval increases.
-   * @type Integer
-   */
-  maxAbsenceInterval: 1 * MILLIS_IN_DAY,
-
-  /**
-   * Minimal time interval before retrying a download after an error.
-   * @type Integer
-   */
-  minRetryInterval: 1 * MILLIS_IN_DAY,
-
-  /**
-   * Maximal allowed expiration interval, larger expiration intervals will be
-   * corrected.
-   * @type Integer
-   */
-  maxExpirationInterval: 14 * MILLIS_IN_DAY,
-
-  /**
-   * Maximal number of redirects before the download is considered as failed.
-   * @type Integer
-   */
-  maxRedirects: 5,
-
-  /**
-   * Called whenever expiration intervals for an object need to be adapted.
-   * @type Function
-   */
-  onExpirationChange: null,
-
-  /**
-   * Callback to be triggered whenever a download starts.
-   * @type Function
-   */
-  onDownloadStarted: null,
-
-  /**
-   * Callback to be triggered whenever a download finishes successfully. The
-   * callback can return an error code to indicate that the data is wrong.
-   * @type Function
-   */
-  onDownloadSuccess: null,
-
-  /**
-   * Callback to be triggered whenever a download fails.
-   * @type Function
-   */
-  onDownloadError: null,
-
-  /**
-   * Checks whether anything needs downloading.
-   */
-  _doCheck: function()
-  {
-    let now = Date.now();
-    for (let downloadable of this.dataSource())
-    {
-      if (downloadable.lastCheck && now - downloadable.lastCheck > this.maxAbsenceInterval)
-      {
-        // No checks for a long time interval - user must have been offline, e.g.
-        // during a weekend. Increase soft expiration to prevent load peaks on the
-        // server.
-        downloadable.softExpiration += now - downloadable.lastCheck;
-      }
-      downloadable.lastCheck = now;
-
-      // Sanity check: do expiration times make sense? Make sure people changing
-      // system clock don't get stuck with outdated subscriptions.
-      if (downloadable.hardExpiration - now > this.maxExpirationInterval)
-        downloadable.hardExpiration = now + this.maxExpirationInterval;
-      if (downloadable.softExpiration - now > this.maxExpirationInterval)
-        downloadable.softExpiration = now + this.maxExpirationInterval;
-
-      // Notify the caller about changes to expiration parameters
-      if (this.onExpirationChange)
-        this.onExpirationChange(downloadable);
-
-      // Does that object need downloading?
-      if (downloadable.softExpiration > now && downloadable.hardExpiration > now)
-        continue;
-
-      // Do not retry downloads too often
-      if (downloadable.lastError && now - downloadable.lastError < this.minRetryInterval)
-        continue;
-
-      this._download(downloadable, 0);
-    }
-  },
-
-  /**
-   * Stops the periodic checks.
-   */
-  cancel: function()
-  {
-    this._timer.cancel();
-  },
-
-  /**
-   * Checks whether an address is currently being downloaded.
-   */
-  isDownloading: function(/**String*/ url) /**Boolean*/
-  {
-    return url in this._downloading;
-  },
-
-  /**
-   * Starts downloading for an object.
-   */
-  download: function(/**Downloadable*/ downloadable)
-  {
-    // Make sure to detach download from the current execution context
-    Utils.runAsync(this._download.bind(this, downloadable, 0));
-  },
-
-  /**
-   * Generates the real download URL for an object by appending various
-   * 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) +
-        "&downloadCount=" + encodeURIComponent(downloadCount);
-    return url;
-  },
-
-  _download: function(downloadable, redirects)
-  {
-    if (this.isDownloading(downloadable.url))
-      return;
-
-    let downloadUrl = this.getDownloadUrl(downloadable);
-    let request = null;
-
-    let errorCallback = function errorCallback(error)
-    {
-      let channelStatus = -1;
-      try
-      {
-        channelStatus = request.channel.status;
-      } catch (e) {}
-
-      let responseStatus = request.status;
-
-      Cu.reportError("Adblock Plus: Downloading URL " + downloadable.url + " failed (" + error + ")\n" +
-                     "Download address: " + downloadUrl + "\n" +
-                     "Channel status: " + channelStatus + "\n" +
-                     "Server response: " + responseStatus);
-
-      if (this.onDownloadError)
-      {
-        // Allow one extra redirect if the error handler gives us a redirect URL
-        let redirectCallback = null;
-        if (redirects <= this.maxRedirects)
-        {
-          redirectCallback = function redirectCallback(url)
-          {
-            downloadable.redirectURL = url;
-            this._download(downloadable, redirects + 1);
-          }.bind(this);
-        }
-
-        this.onDownloadError(downloadable, downloadUrl, error, channelStatus, responseStatus, redirectCallback);
-      }
-    }.bind(this);
-
-    try
-    {
-      request = new XMLHttpRequest();
-      request.mozBackgroundRequest = true;
-      request.open("GET", downloadUrl);
-    }
-    catch (e)
-    {
-      errorCallback("synchronize_invalid_url");
-      return;
-    }
-
-    try {
-      request.overrideMimeType("text/plain");
-      request.channel.loadFlags = request.channel.loadFlags |
-                                  request.channel.INHIBIT_CACHING |
-                                  request.channel.VALIDATE_ALWAYS;
-
-      // Override redirect limit from preferences, user might have set it to 1
-      if (request.channel instanceof Ci.nsIHttpChannel)
-        request.channel.redirectionLimit = this.maxRedirects;
-    }
-    catch (e)
-    {
-      Cu.reportError(e)
-    }
-
-    request.addEventListener("error", function(event)
-    {
-      if (onShutdown.done)
-        return;
-
-      delete this._downloading[downloadable.url];
-      errorCallback("synchronize_connection_error");
-    }.bind(this), false);
-
-    request.addEventListener("load", function(event)
-    {
-      if (onShutdown.done)
-        return;
-
-      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));
-    }.bind(this), false);
-
-    request.send(null);
-
-    this._downloading[downloadable.url] = true;
-    if (this.onDownloadStarted)
-      this.onDownloadStarted(downloadable);
-  },
-
-  /**
-   * Produces a soft and a hard expiration interval for a given supplied
-   * expiration interval.
-   * @return {Array} soft and hard expiration interval
-   */
-  processExpirationInterval: function(/**Integer*/ interval)
-  {
-    interval = Math.min(Math.max(interval, 0), this.maxExpirationInterval);
-    let soft = Math.round(interval * (Math.random() * 0.4 + 0.8));
-    let hard = interval * 2;
-    let now = Date.now();
-    return [now + soft, now + hard];
-  }
-};
-
-/**
- * An object that can be downloaded by the downloadable
- * @param {String} url  URL that has to be requested for the object
- * @constructor
- */
-let Downloadable = exports.Downloadable = function Downloadable(url)
-{
-  this.url = url;
-}
-Downloadable.prototype =
-{
-  /**
-   * URL that has to be requested for the object.
-   * @type String
-   */
-  url: null,
-
-  /**
-   * URL that the download was redirected to if any.
-   * @type String
-   */
-  redirectURL: null,
-
-  /**
-   * Time of last download error or 0 if the last download was successful.
-   * @type Integer
-   */
-  lastError: 0,
-
-  /**
-   * Time of last check whether the object needs downloading.
-   * @type Integer
-   */
-  lastCheck: 0,
-
-  /**
-   * Object version corresponding to the last successful download.
-   * @type Integer
-   */
-  lastVersion: 0,
-
-  /**
-   * Soft expiration interval, will increase if no checks are performed for a
-   * 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,
-};