except RepositoryError, e:

            log.error(traceback.format_exc())

            h.flash(str(e), category='warning')

            if not partial:

                redirect(h.url('changelog_home', repo_name=repo.repo_name))

            raise HTTPBadRequest()

    def _graph(self, repo, revs_int, repo_size, size, p):

        """

        Generates a DAG graph for repo

        :param repo:

        :param revs_int:

        :param repo_size:

        :param size:

        :param p:

        """

        if not revs_int:

            c.jsdata = json.dumps([])

            return

        data = []

        revs = revs_int

        dag = _dagwalker(repo, revs, repo.alias)

        dag = _colored(dag)

        for (id, type, ctx, vtx, edges) in dag:

            data.append(['', vtx, edges])

        c.jsdata = json.dumps(data)

    @LoginRequired()

    @HasRepoPermissionAnyDecorator('repository.read', 'repository.write',

                                   'repository.admin')

    def index(self, repo_name, revision=None, f_path=None):

        limit = 100

        default = 20

        if request.GET.get('size'):

            c.size = max(min(safe_int(request.GET.get('size')), limit), 1)

            session['changelog_size'] = c.size

            session.save()

        else:

            c.size = int(session.get('changelog_size', default))

        # min size must be 1

        c.size = max(c.size, 1)

        p = safe_int(request.GET.get('page', 1), 1)

        branch_name = request.GET.get('branch', None)

        c.changelog_for_path = f_path

        try:

            if f_path:

                log.debug('generating changelog for path %s' % f_path)

                # get the history for the file !

                tip_cs = c.rhodecode_repo.get_changeset()

                try:

                    collection = tip_cs.get_file_history(f_path)

                except (NodeDoesNotExistError, ChangesetError):

                    #this node is not present at tip !

                    try:

                        cs = self.__get_css_or_redirect(revision, repo_name)

                        collection = cs.get_file_history(f_path)

                    except RepositoryError, e:

                        h.flash(str(e), category='warning')

                        redirect(h.url('changelog_home', repo_name=repo_name))

                collection = list(reversed(collection))

            else:

                collection = c.rhodecode_repo.get_changesets(start=0,

                                                        branch_name=branch_name)

            c.total_cs = len(collection)

            c.pagination = RepoPage(collection, page=p, item_count=c.total_cs,

                                    items_per_page=c.size, branch=branch_name,)

            collection = list(c.pagination)

            page_revisions = [x.raw_id for x in c.pagination]

            c.comments = c.rhodecode_db_repo.get_comments(page_revisions)

            c.statuses = c.rhodecode_db_repo.statuses(page_revisions)

        except (EmptyRepositoryError), e:

            h.flash(str(e), category='warning')

            return redirect(url('summary_home', repo_name=c.repo_name))

        except (RepositoryError, ChangesetDoesNotExistError, Exception), e:

            log.error(traceback.format_exc())

            h.flash(str(e), category='error')

            return redirect(url('changelog_home', repo_name=c.repo_name))

        c.branch_name = branch_name

        c.branch_filters = [('', _('All Branches'))] + \

            [(k, k) for k in c.rhodecode_repo.branches.keys()]

        if c.rhodecode_repo.closed_branches:

            prefix = _('(closed)') + ' '

            c.branch_filters += [('-', '-')] + \

                [(k, prefix + k) for k in c.rhodecode_repo.closed_branches.keys()]

        _revs = []

        if not f_path:

            _revs = [x.revision for x in c.pagination]

        self._graph(c.rhodecode_repo, _revs, c.total_cs, c.size, p)