Issue 5146 - Implement DownloadableSubscription parsing in C++

lib/synchronizer.js

 /*
  * This file is part of Adblock Plus <https://adblockplus.org/>,
  * Copyright (C) 2006-present 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 10 matching lines @@
  * @fileOverview Manages synchronization of filter subscriptions.
  */
 
 const {Downloader, Downloadable,
        MILLIS_IN_SECOND, MILLIS_IN_MINUTE,
        MILLIS_IN_HOUR, MILLIS_IN_DAY} = require("downloader");
 const {FilterStorage} = require("filterStorage");
 const {FilterNotifier} = require("filterNotifier");
 const {Prefs} = require("prefs");
 const {Subscription, DownloadableSubscription} = require("subscriptionClasses");
-const {Utils} = require("utils");
 
 const INITIAL_DELAY = 1 * MILLIS_IN_MINUTE;
 const CHECK_INTERVAL = 1 * MILLIS_IN_HOUR;
 const DEFAULT_EXPIRATION_INTERVAL = 5 * MILLIS_IN_DAY;
 
 /**
  * The object providing actual downloading functionality.
  * @type {Downloader}
  */
 let downloader = null;
@@ skipping 103 matching lines @@
 
   _onDownloadSuccess(downloadable, responseText, errorCallback,
                      redirectCallback)
   {
     let lines = responseText.split(/[\r\n]+/);
     let headerMatch = /\[Adblock(?:\s*Plus\s*([\d.]+)?)?\]/i.exec(lines[0]);
     if (!headerMatch)
       return errorCallback("synchronize_invalid_data");
     let minVersion = headerMatch[1];
 
-    let parser = subscription.parseDownload();
-
-    // Don't remove parameter comments immediately but add them to a list first,
-    // they need to be considered in the checksum calculation.
-    for (let i = 0; i < lines.length; i++)
-    {
-      let match = /^\s*!\s*(\w+)\s*:\s*(.*)/.exec(lines[i]);
-      if (match)
-      {
-        let keyword = match[1].toLowerCase();
-        let value = match[2];
-        if (keyword == "checksum")
-        {
-          lines.splice(i--, 1);
-          let checksum = Utils.generateChecksum(lines);
-          if (checksum && checksum != value.replace(/=+$/, ""))
-            return errorCallback("synchronize_checksum_mismatch");
-        }
-      }
-    }
+    let parser = DownloadableSubscription.parseDownload();
 
     // Process filters
-    lines.shift();
     for (let line of lines)
       parser.process(line);

[hub, 2017/11/13 22:35:28]

I intend to parse the whole buffer, but for now we'll parse line by line.

 
     if (parser.redirect)
-      return redirectCallback(parser.redirect);

[hub, 2017/11/13 22:35:28]

This can be better as we should catch the redirect earlier.

+    {
+      let {redirect} = parser;
+      parser.delete();
+      return redirectCallback(redirect);
+    }
 
     // Handle redirects
     let subscription = Subscription.fromURL(downloadable.redirectURL ||
                                             downloadable.url);
     if (downloadable.redirectURL &&
         downloadable.redirectURL != downloadable.url)
     {
       let oldSubscription = Subscription.fromURL(downloadable.url);
       subscription.title = oldSubscription.title;
       subscription.disabled = oldSubscription.disabled;
       subscription.lastCheck = oldSubscription.lastCheck;
 
-      let listed = (oldSubscription.url in FilterStorage.knownSubscriptions);
+      let {listed} = oldSubscription;
       if (listed)
         FilterStorage.removeSubscription(oldSubscription);
-
-      delete Subscription.knownSubscriptions[oldSubscription.url];
 
       if (listed)
         FilterStorage.addSubscription(subscription);
     }
 
     // The download actually succeeded
     subscription.lastSuccess = subscription.lastDownload = Math.round(
       Date.now() / MILLIS_IN_SECOND
     );
     subscription.downloadStatus = "synchronize_ok";
@@ skipping 16 matching lines @@
       if (url && (url.protocol == "http:" || url.protocol == "https:"))
         subscription.homepage = url.href;
     }
 
     if (minVersion)
       subscription.requiredVersion = minVersion;
     else
       delete subscription.requiredVersion;
 
     let expirationInterval = DEFAULT_EXPIRATION_INTERVAL;
-    let expiration = parser.finalize();
+    let expiration = parser.finalize(subscription);
     if (expiration != 0)
       expirationInterval = expiration;
 
     let [
       softExpiration,
       hardExpiration
     ] = downloader.processExpirationInterval(expirationInterval);
     subscription.softExpiration = Math.round(softExpiration / MILLIS_IN_SECOND);
     subscription.expires = Math.round(hardExpiration / MILLIS_IN_SECOND);
 
@@ skipping 40 matching lines @@
         request.open("GET", fallbackURL);
         request.overrideMimeType("text/plain");
         request.channel.loadFlags = request.channel.loadFlags |
                                     request.channel.INHIBIT_CACHING |
                                     request.channel.VALIDATE_ALWAYS;
         request.addEventListener("load", ev =>
         {
           if (onShutdown.done)
             return;
 
-          if (!(subscription.url in FilterStorage.knownSubscriptions))
+          if (!subscription.listed)
             return;
 
           let match = /^(\d+)(?:\s+(\S+))?$/.exec(request.responseText);
           if (match && match[1] == "301" &&    // Moved permanently
               match[2] && /^https?:\/\//i.test(match[2]))
           {
             redirectCallback(match[2]);
           }
           else if (match && match[1] == "410") // Gone
           {
             let data = "[Adblock]\n" +
-              subscription.filters.map(f => f.text).join("\n");
+              Array.from(subscription.filters, f => f.text).join("\n");
             redirectCallback("data:text/plain," + encodeURIComponent(data));
           }
         }, false);
         request.send(null);
       }
     }
   }
 };
 Synchronizer.init();