def __before__(self):

        super(ChangelogController, self).__before__()

    def index(self):

        limit = 100

        default = 20

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

            try:

                int_size = int(request.params.get('size'))

            except ValueError:

                int_size = default

            int_size = int_size if int_size <= limit else limit

            c.size = int_size

            session['changelog_size'] = c.size

            session.save()

        else:

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

        p = int(request.params.get('page', 1))

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

        c.total_cs = len(c.rhodecode_repo)

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

                            items_per_page=c.size, branch_name=branch_name)

        return render('changelog/changelog.html')

        """

        Generates a DAG graph for mercurial

        :param repo: repo instance

        :param size: number of commits to show

        :param p: page number

        """

        if not repo.revisions or repo.alias == 'git':

            c.jsdata = json.dumps([])

            return

        offset = 1 if p == 1 else  ((p - 1) * revcount + 1)

        rev_start = repo.revisions.index(repo.revisions[(-1 * offset)])

        rev_end = max(0, rev_start - revcount)

        dag = graph_rev(repo._repo, rev_start, rev_end)

        c.dag = tree = list(colored(dag))

        data = []

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

            if type != CHANGESET:

                continue

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

        c.jsdata = json.dumps(data)