extras.py 文件源码

def start_replication(self, slot_name=None, slot_type=None, start_lsn=0,
                          timeline=0, options=None, decode=False):
        """Start replication stream."""

        command = "START_REPLICATION "

        if slot_type is None:
            slot_type = self.connection.replication_type

        if slot_type == REPLICATION_LOGICAL:
            if slot_name:
                command += "SLOT %s " % quote_ident(slot_name, self)
            else:
                raise psycopg2.ProgrammingError(
                    "slot name is required for logical replication")

            command += "LOGICAL "

        elif slot_type == REPLICATION_PHYSICAL:
            if slot_name:
                command += "SLOT %s " % quote_ident(slot_name, self)
            # don't add "PHYSICAL", before 9.4 it was just START_REPLICATION XXX/XXX

        else:
            raise psycopg2.ProgrammingError(
                "unrecognized replication type: %s" % repr(slot_type))

        if type(start_lsn) is str:
            lsn = start_lsn.split('/')
            lsn = "%X/%08X" % (int(lsn[0], 16), int(lsn[1], 16))
        else:
            lsn = "%X/%08X" % ((start_lsn >> 32) & 0xFFFFFFFF,
                               start_lsn & 0xFFFFFFFF)

        command += lsn

        if timeline != 0:
            if slot_type == REPLICATION_LOGICAL:
                raise psycopg2.ProgrammingError(
                    "cannot specify timeline for logical replication")

            command += " TIMELINE %d" % timeline

        if options:
            if slot_type == REPLICATION_PHYSICAL:
                raise psycopg2.ProgrammingError(
                    "cannot specify output plugin options for physical replication")

            command += " ("
            for k, v in options.items():
                if not command.endswith('('):
                    command += ", "
                command += "%s %s" % (quote_ident(k, self), _A(str(v)))
            command += ")"

        self.start_replication_expert(command, decode=decode)

    # allows replication cursors to be used in select.select() directly