def get(self, master_id):
        """
        Get a list of revisions by master ID

        :param master_id:
        :return:
        """
        collection_name = self.request.headers.get("collection")
        self.client = BaseAsyncMotorDocument("%s_revisions" % collection_name)

        limit = self.get_query_argument("limit", 2)
        add_current_revision = self.get_arg_value_as_type("addCurrent",
                                                          "false")
        show_history = self.get_arg_value_as_type("showHistory", "false")

        objects_processed = []

        if isinstance(limit, unicode):
            limit = int(limit)

        objects = yield self.client.find({"master_id": master_id,
                                          "processed": False},
                                         orderby="toa",
                                         order_by_direction=1,
                                         page=0,
                                         limit=20)

        # If this is a document that should have a revision and doesn't we
        # orchestratioin creation of the first one
        if len(objects) == 0:

            new_revision = yield self.__lazy_migration(master_id)
            if not new_revision:
                return

        if show_history:
            objects_processed = yield self.client.find({"master_id": master_id,
                                                        "processed": True},
                                                       orderby="toa",
                                                       order_by_direction=-1,
                                                       page=0,
                                                       limit=limit)

        elif add_current_revision:
            objects_processed = yield self.client.find({"master_id": master_id,
                                                        "processed": True},
                                                       orderby="toa",
                                                       order_by_direction=-1,
                                                       page=0,
                                                       limit=1)

        if len(objects_processed) > 0:
            objects_processed = objects_processed[::-1]
            objects_processed[-1]["current"] = True
            objects = objects_processed + objects

        self.write({
            "count": len(objects),
            "results": objects
        })
Get a list of revisions by master ID

        :param master_id:
        :return: