""" Copyright (C) Internet Systems Consortium, Inc. ("ISC") SPDX-License-Identifier: MPL-2.0 This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, you can obtain one at https://mozilla.org/MPL/2.0/. See the COPYRIGHT file distributed with this work for additional information regarding copyright ownership. """ from collections.abc import AsyncGenerator import dns.rcode import dns.rdatatype import dns.rrset from isctest.asyncserver import ( AsyncDnsServer, DnsResponseSend, IgnoreAllQueries, QnameHandler, QueryContext, ResponseHandler, ) class FooInfoHandler(QnameHandler, IgnoreAllQueries): qnames = ["foo.info."] class FallbackHandler(ResponseHandler): async def get_responses( self, qctx: QueryContext ) -> AsyncGenerator[DnsResponseSend, None]: name = "below.www.example.com." ns_name = f"ns.{name}" ns_rrset = dns.rrset.from_text( name, 300, qctx.qclass, dns.rdatatype.NS, ns_name ) a_rrset = dns.rrset.from_text( ns_name, 300, qctx.qclass, dns.rdatatype.A, "10.53.0.3" ) qctx.response.authority.append(ns_rrset) qctx.response.additional.append(a_rrset) yield DnsResponseSend(qctx.response) def main() -> None: server = AsyncDnsServer(default_rcode=dns.rcode.NOERROR, default_aa=False) server.install_response_handlers(FooInfoHandler(), FallbackHandler()) server.run() if __name__ == "__main__": main()