Reimplement 'reclimit/ans7' server using AsyncDnsServer

Replace the Perl implementation with a Python one. The old server's
query counter doesn't work properly. Make no attempt at imitating this.

diff --git a/bin/tests/system/reclimit/ans7/ans.pl b/bin/tests/system/reclimit/ans7/ans.pl
deleted file mode 100644 (file)
index 52110f1..0000000
--- a/bin/tests/system/reclimit/ans7/ans.pl
+++ /dev/null
@@ -1,88 +0,0 @@
-#!/usr/bin/env perl
-
-# 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.
-
-use strict;
-use warnings;
-
-use IO::File;
-use Getopt::Long;
-use Net::DNS::Nameserver;
-
-my $pidf = new IO::File "ans.pid", "w" or die "cannot open pid file: $!";
-print $pidf "$$\n" or die "cannot write pid file: $!";
-$pidf->close or die "cannot close pid file: $!";
-sub rmpid { unlink "ans.pid"; exit 1; };
-sub term { };
-
-$SIG{INT} = \&rmpid;
-if ($Net::DNS::VERSION >= 1.42) {
-    $SIG{TERM} = \&term;
-} else {
-    $SIG{TERM} = \&rmpid;
-}
-
-my $count = 0;
-
-my $localaddr = "10.53.0.7";
-my $localport = int($ENV{'PORT'});
-if (!$localport) { $localport = 5300; }
-my $verbose = 0;
-
-sub reply_handler {
-    my ($qname, $qclass, $qtype, $peerhost, $query, $conn) = @_;
-    my ($rcode, @ans, @auth, @add);
-
-    print ("request: $qname/$qtype\n");
-    STDOUT->flush();
-
-    $count += 1;
-
-    if ($qname eq "count" ) {
-        if ($qtype eq "TXT") {
-            my ($ttl, $rdata) = (0, "$count");
-            my $rr = new Net::DNS::RR("$qname $ttl $qclass $qtype $rdata");
-            push @ans, $rr;
-            print ("\tcount: $count\n");
-        }
-        $rcode = "NOERROR";
-    } elsif ($qname eq "reset") {
-        $count = 0;
-        $rcode = "NOERROR";
-    } else {
-        $rcode = "REFUSED";
-    }
-
-    # mark the answer as authoritative (by setting the 'aa' flag
-    return ($rcode, \@ans, \@auth, \@add, { aa => 1 });
-}
-
-GetOptions(
-    'port=i' => \$localport,
-    'verbose!' => \$verbose,
-);
-
-my $ns = Net::DNS::Nameserver->new(
-    LocalAddr => $localaddr,
-    LocalPort => $localport,
-    ReplyHandler => \&reply_handler,
-    Verbose => $verbose,
-);
-
-if ($Net::DNS::VERSION >= 1.42) {
-    $ns->start_server();
-    select(undef, undef, undef, undef);
-    $ns->stop_server();
-    unlink "ans.pid";
-} else {
-    $ns->main_loop;
-}

diff --git a/bin/tests/system/reclimit/ans7/ans.py b/bin/tests/system/reclimit/ans7/ans.py
new file mode 100644 (file)
index 0000000..05b24aa
--- /dev/null
+++ b/bin/tests/system/reclimit/ans7/ans.py
@@ -0,0 +1,41 @@
+"""
+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
+
+from isctest.asyncserver import AsyncDnsServer, DnsResponseSend, QueryContext
+
+from ..reclimit_ans import ReclimitHandler, ReclimitStateHandler
+
+
+class FallbackRefusedHandler(ReclimitHandler):
+    async def get_responses(
+        self, qctx: QueryContext
+    ) -> AsyncGenerator[DnsResponseSend, None]:
+        qctx.response.set_rcode(dns.rcode.REFUSED)
+        yield DnsResponseSend(qctx.response)
+
+
+def main() -> None:
+    server = AsyncDnsServer(default_aa=True, default_rcode=dns.rcode.NOERROR)
+    server.install_response_handlers(
+        state_handler := ReclimitStateHandler(),
+        FallbackRefusedHandler(state_handler),
+    )
+    server.run()
+
+
+if __name__ == "__main__":
+    main()