Added huge diff protection for RSS/ATOM feeds.

It can really be a performance killer for huge diffs.

rhodecode/controllers/feed.py

@@ -1,128 +1,134 b''
 # -*- coding: utf-8 -*-
 """
     rhodecode.controllers.feed
     ~~~~~~~~~~~~~~~~~~~~~~~~~~
 
     Feed controller for rhodecode
 
     :created_on: Apr 23, 2010
     :author: marcink
     :copyright: (C) 2010-2012 Marcin Kuzminski <[e-mail]>
     :license: GPLv3, see COPYING for more details.
 """
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import logging
 
 from pylons import url, response, tmpl_context as c
 from pylons.i18n.translation import _
 
 from webhelpers.feedgenerator import Atom1Feed, Rss201rev2Feed
 
 from rhodecode.lib import helpers as h
 from rhodecode.lib.auth import LoginRequired, HasRepoPermissionAnyDecorator
 from rhodecode.lib.base import BaseRepoController
 from rhodecode.lib.diffs import DiffProcessor
 
 log = logging.getLogger(__name__)
 
 
 class FeedController(BaseRepoController):
 
     @LoginRequired(api_access=True)
     @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',
                                    'repository.admin')
     def __before__(self):
         super(FeedController, self).__before__()
         #common values for feeds
         self.description = _('Changes on %s repository')
         self.title = self.title = _('%s %s feed') % (c.rhodecode_name, '%s')
         self.language = 'en-us'
         self.ttl = "5"
         self.feed_nr = 20
 
     def _get_title(self, cs):
         return "%s" % (
             h.shorter(cs.message, 160)
         )
 
     def __changes(self, cs):
         changes = []
-
-        diffprocessor = DiffProcessor(cs.diff())
+        _diff = cs.diff()
+        # we need to protect from parsing huge diffs here other way
+        # we can kill the server, 32*1024 chars is a reasonable limit
+        HUGE_DIFF = 32 * 1024
+        if len(_diff) > HUGE_DIFF:
+            changes = ['\n ' + _('Changeset was too big and was cut off...')]
+            return changes
+        diffprocessor = DiffProcessor(_diff)
         stats = diffprocessor.prepare(inline_diff=False)
         for st in stats:
             st.update({'added': st['stats'][0],
                        'removed': st['stats'][1]})
             changes.append('\n %(operation)s %(filename)s '
                            '(%(added)s lines added, %(removed)s lines removed)'
                             % st)
         return changes
 
     def __get_desc(self, cs):
         desc_msg = []
         desc_msg.append('%s %s %s:<br/>' % (cs.author, _('commited on'),
                                            h.fmt_date(cs.date)))
         desc_msg.append('<pre>')
         desc_msg.append(cs.message)
         desc_msg.append('\n')
         desc_msg.extend(self.__changes(cs))
         desc_msg.append('</pre>')
         return desc_msg
 
     def atom(self, repo_name):
         """Produce an atom-1.0 feed via feedgenerator module"""
         feed = Atom1Feed(
              title=self.title % repo_name,
              link=url('summary_home', repo_name=repo_name,
                       qualified=True),
              description=self.description % repo_name,
              language=self.language,
              ttl=self.ttl
         )
 
         for cs in reversed(list(c.rhodecode_repo[-self.feed_nr:])):
             feed.add_item(title=self._get_title(cs),
                           link=url('changeset_home', repo_name=repo_name,
                                    revision=cs.raw_id, qualified=True),
                           author_name=cs.author,
                           description=''.join(self.__get_desc(cs)),
                           pubdate=cs.date,
                           )
 
         response.content_type = feed.mime_type
         return feed.writeString('utf-8')
 
     def rss(self, repo_name):
         """Produce an rss2 feed via feedgenerator module"""
         feed = Rss201rev2Feed(
             title=self.title % repo_name,
             link=url('summary_home', repo_name=repo_name,
                      qualified=True),
             description=self.description % repo_name,
             language=self.language,
             ttl=self.ttl
         )
 
         for cs in reversed(list(c.rhodecode_repo[-self.feed_nr:])):
             feed.add_item(title=self._get_title(cs),
                           link=url('changeset_home', repo_name=repo_name,
                                    revision=cs.raw_id, qualified=True),
                           author_name=cs.author,
                           description=''.join(self.__get_desc(cs)),
                           pubdate=cs.date,
                          )
 
         response.content_type = feed.mime_type
         return feed.writeString('utf-8')