Tests: SRV records resolving.

tests/upstream_srv.t

@@ -0,0 +1,168 @@
+#!/usr/bin/perl
+
+# (C) 2023 Web Server LLC
+
+# Tests for upstream SRV records.
+
+###############################################################################
+
+use warnings;
+use strict;
+#use Data::Dumper;
+
+use Test::More;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+eval { require JSON::PP; };
+plan(skip_all => "JSON::PP not installed") if $@;
+
+# the test depends on availability of 127.0.0.0/8 subnet on targets
+plan(skip_all => 'OS is not linux') if $^O ne 'linux';
+
+my $t = Test::Nginx->new()->has(qw/http proxy upstream_zone/)
+	->has_daemon("dnsmasq")->plan(3)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+# to (possibly) improve coverage a bit
+worker_processes 4;
+
+events {
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    upstream u {
+        zone z 1m;
+        server backends.example.com service=http resolve;
+
+        resolver 127.0.0.1:5454 valid=1s;
+    }
+
+    server {
+        listen       127.0.0.1:%%PORT_8080%%;
+        server_name  localhost;
+
+        location / {
+            proxy_pass http://u;
+        }
+
+        location /api/ {
+            api /;
+        }
+    }
+
+    # backends
+    server {
+        error_log backend1.log debug;
+        listen 127.0.0.1:%%PORT_8081%%;
+        location / { return 200 "B1"; }
+    }
+    server {
+        error_log backend2.log debug;
+        listen 127.0.0.2:%%PORT_8082%%;
+        location / { return 200 "B2"; }
+    }
+}
+
+EOF
+
+my $tdir = $t->testdir();
+
+# TODO: use substituted ports for parallel execution for DNS server
+$t->write_file_expand('dns.conf', <<'EOF');
+# listen on this port
+port=5454
+# no need for dhcp
+no-dhcp-interface=
+# do not read /etc/hosts
+no-hosts
+# do not read /etc/resolv.conf
+no-resolv
+# take records from this fil
+addn-hosts=%%TESTDIR%%/test_hosts
+
+# SRV records
+srv-host=_http._tcp.backends.example.com,b1.example.com,%%PORT_8081%%
+srv-host=_http._tcp.backends.example.com,b2.example.com,%%PORT_8082%%
+EOF
+
+# ipv6 entries are stubs for resolver
+$t->write_file_expand('test_hosts', <<'EOF');
+127.0.0.1  b1.example.com
+127.0.0.2  b2.example.com
+::1 b1.example.com
+::1 b2.example.com
+EOF
+
+
+my $dconf = $t->testdir()."/dns.conf";
+
+$t->run_daemon('dnsmasq', '-C', $tdir."/dns.conf", '-k', "--log-facility=$tdir/dns.log", '-q');
+$t->run();
+
+# let the dnsmasq execute;
+# TODO: waitport() for UDP sockets; avoid delay
+select undef, undef, undef, 3;
+
+###############################################################################
+
+my @ports = my ($port1, $port2) = (port(8081), port(8082));
+
+my ($j, $v);
+
+# give 1 request for each backend
+http_get('/'); http_get('/');
+# TODO: no idea what 1st backend is going to be; maybe IPv6, which is not listened
+
+# expect that upstream contains addresses from 'test_hosts' file
+
+$j = get_json("/api/status/http/upstreams/u/peers/");
+
+my $n4 = 0;
+
+foreach my $addr ( keys %$j ) {
+
+    #print(Dumper($j->{$addr}));
+
+    if ($addr eq "127.0.0.1:$port1") {
+        $n4 = $n4 + 1;
+        is($j->{$addr}->{'server'}, 'backends.example.com', 'b1 address resolved');
+    }
+    if ($addr eq "127.0.0.2:$port2") {
+        $n4 = $n4 + 1;
+        is($j->{$addr}->{'server'}, 'backends.example.com', 'b2 address resolved');
+    }
+}
+
+is($n4, 2, 'backends.example.com resolved into 2 ipv4 addresses');
+
+
+###############################################################################
+
+sub get_json {
+    my ($uri) = @_;
+    my $response = http_get($uri);
+    my ($headers,$body) =  split /\n\r/, $response, 2;
+    #print($body);
+    my $json;
+    eval { $json = JSON::PP::decode_json($body) };
+    if ($@) {
+        return undef;
+    }
+
+    return $json;
+}
+