Method _format_event

opcua/server/history_sql.py:284–308

Convert an event object triggered by the subscription into ordered lists for the SQL insert string Args: event: The event returned by the subscription Returns: List of event fields (SQL column names), List of '?' placeholders, Tuple of variant binaries

(self, event)

        return start_time, end_time, order, limit

    def _format_event(self, event):
        """
        Convert an event object triggered by the subscription into ordered lists for the SQL insert string

        Args:
            event: The event returned by the subscription

        Returns: List of event fields (SQL column names), List of '?' placeholders, Tuple of variant binaries

        """
        placeholders = []
        ev_variant_binaries = []

        ev_variant_dict = event.get_event_props_as_fields_dict()
        names = list(ev_variant_dict.keys())
        names.sort()  # sort alphabetically since dict is not sorted

        # split dict into two synchronized lists which will be converted to SQL strings
        # note that the variants are converted to binary objects for storing in SQL BLOB format
        for name in names:
            variant = ev_variant_dict[name]
            placeholders.append('?')
            ev_variant_binaries.append(sqlite3.Binary(variant_to_binary(variant)))

        return self._list_to_sql_str(names), self._list_to_sql_str(placeholders, False), tuple(ev_variant_binaries)

    def _get_event_columns(self, ev_fields):
        fields = []