def update(self, doc, process=None):
        if process is None:
            pk = 'id'
            id = doc.id
            doc.synced = False
            set = doc
        elif process == UPDATE_PROCESS:
            if self.db.docs.find({'sid': doc.sid}).count() == 0:
                return self.insert(doc, synced=True)
            pk = 'sid'
            id = doc.sid
            doc.synced = not doc.merged() # must be commited if was merged
            doc.merged(False)
            set = {'tid': doc.tid, 'data': doc.data, 'user': doc.user,
                   'public': doc.public, 'synced': doc.synced}
        elif process == COMMIT_PROCESS:
            pk = 'id'
            id = doc.id
            doc.synced = True
            set = {'sid': doc.sid, 'tid': doc.tid, 'synced': doc.synced}
        else:
            raise DatabaseException('Incorrect update process')

        try:
            rs = self.db.docs.update({pk: id}, {'$set': set}, safe=True)
            assert rs['n'] == 1
        except Exception as e:
            raise DatabaseException(e)
        return doc
def is_immutable_rev_checkout(self, url, dest):
        # type: (str, str) -> bool
        _, rev_options = self.get_url_rev_options(hide_url(url))
        if not rev_options.rev:
            return False
        if not self.is_commit_id_equal(dest, rev_options.rev):
            # the current commit is different from rev,
            # which means rev was something else than a commit hash
            return False
        # return False in the rare case rev is both a commit hash
        # and a tag or a branch; we don't want to cache in that case
        # because that branch/tag could point to something else in the future
        is_tag_or_branch = bool(
            self.get_revision_sha(dest, rev_options.rev)[0]
        )
        return not is_tag_or_branch