view stream_proxy_half_close.t @ 1752:ba6e24e38f03

Tests: improved stop_daemons() to send signal again. As was observed, it's possible that a signal to complete a uwsgi daemon can be ignored while it is starting up, which results in tests hang due to eternal waiting on child processes termination. Notably, it is seen when running tests with a high number of prove jobs on a low-profile VM against nginx with broken modules and/or configuration. To reproduce: $ TEST_NGINX_GLOBALS=ERROR prove -j16 uwsgi*.t Inspecting uwsgi under ktrace on FreeBSD confirms that a SIGTERM signal is ignored at the very beginning of uwsgi startup. It is then replaced with a default action after listen(), thus waiting until uwsgi is ready to accept new TCP connections doesn't completely solve the hang window. The fix is to retry sending a signal some time after waitpid(WNOHANG) continuously demonstrated no progress with reaping a signaled process. It is modelled after f13ead27f89c that improved stop() for nginx.
author Sergey Kandaurov <pluknet@nginx.com>
date Wed, 29 Dec 2021 22:29:23 +0300
parents 8bdf548487f6
children 2a0a6035a1af
line wrap: on
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#!/usr/bin/perl

# (C) Sergey Kandaurov
# (C) Nginx, Inc.

# Tests for stream proxy_half_close directive.

###############################################################################

use warnings;
use strict;

use Test::More;

use IO::Select;

BEGIN { use FindBin; chdir($FindBin::Bin); }

use lib 'lib';
use Test::Nginx;

###############################################################################

select STDERR; $| = 1;
select STDOUT; $| = 1;

my $t = Test::Nginx->new()->has(qw/stream/);

$t->write_file_expand('nginx.conf', <<'EOF');

%%TEST_GLOBALS%%

daemon off;

events {
}

stream {
    %%TEST_GLOBALS_STREAM%%

    server {
        listen      127.0.0.1:8080;
        proxy_pass  127.0.0.1:8081;

        proxy_half_close  on;
    }
}

EOF

$t->try_run('no proxy_half_close')->plan(2);

###############################################################################

my ($s, $u) = pair(8080, 8081);
shutdown($u, 1);
is(proxy($s, $u, 'SEE'), 'SEE', 'half close upstream');

($s, $u) = pair(8080, 8081);
shutdown($s, 1);
is(proxy($u, $s, 'SEE'), 'SEE', 'half close client');

###############################################################################

sub pair {
	my ($server, $backend) = @_;

	my $listen = IO::Socket::INET->new(
		LocalHost => '127.0.0.1:' . port($backend),
		Listen => 5,
		Reuse => 1,
	)
		or die "Can't listen on $server: $!\n";

	my $connect = IO::Socket::INET->new(
		Proto => 'tcp',
		PeerHost => '127.0.0.1:' . port($server),
	)
		or die "Can't connect to $server: $!\n";

	my $accept = $listen->accept() if IO::Select->new($listen)->can_read(3);

	return $connect, $accept;
}

sub proxy {
	my ($from, $to, $msg) = @_;
	proxy_from($from, $msg);
	return proxy_to($to);
}

sub proxy_from {
	my ($s, $msg) = @_;

	local $SIG{PIPE} = 'IGNORE';

	while (IO::Select->new($s)->can_write(5)) {
		my $n = $s->syswrite($msg);
		log_out(substr($msg, 0, $n));
		last unless $n;

		$msg = substr($msg, $n);
		last unless length $msg;
	}
}

sub proxy_to {
	my ($s) = @_;
	my $buf;

	$s->sysread($buf, 1024) if IO::Select->new($s)->can_read(5);

	log_in($buf);
	return $buf;
}

###############################################################################