File: MemcachedTest.pm

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package MemcachedTest;
use strict;
use IO::Socket::INET;
use IO::Socket::UNIX;
use POSIX ":sys_wait_h";
use Exporter 'import';
use Carp qw(croak);
use vars qw(@EXPORT);

# Instead of doing the substitution with Autoconf, we assume that
# cwd == builddir.
use Cwd;
my $builddir = getcwd;

my @unixsockets = ();

@EXPORT = qw(new_memcached sleep
             mem_get_is mem_gets mem_gets_is mem_stats mem_move_time
             supports_sasl free_port supports_drop_priv supports_extstore
             wait_ext_flush supports_tls enabled_tls_testing run_help
             supports_unix_socket get_memcached_exe supports_proxy);

use constant MAX_READ_WRITE_SIZE => 16384;
use constant SRV_CRT => "server_crt.pem";
use constant SRV_KEY => "server_key.pem";
use constant CLIENT_CRT => "client_crt.pem";
use constant CLIENT_KEY => "client_key.pem";
use constant CA_CRT => "cacert.pem";

my $testdir = $builddir . "/t/";
my $client_crt = $testdir. CLIENT_CRT;
my $client_key = $testdir. CLIENT_KEY;
my $server_crt = $testdir . SRV_CRT;
my $server_key = $testdir . SRV_KEY;

my $tls_checked = 0;

sub sleep {
    my $n = shift;
    select undef, undef, undef, $n;
}

# Wait until all items have flushed
sub wait_ext_flush {
    my $sock = shift;
    my $target = shift || 0;
    my $sum = $target + 1;
    while ($sum > $target) {
        my $s = mem_stats($sock, "items");
        $sum = 0;
        for my $key (keys %$s) {
            if ($key =~ m/items:(\d+):number/) {
                # Ignore classes which can contain extstore items
                next if $1 < 3;
                $sum += $s->{$key};
            }
        }
        sleep 1 if $sum > $target;
    }
}

sub mem_stats {
    my ($sock, $type) = @_;
    $type = $type ? " $type" : "";
    print $sock "stats$type\r\n";
    my $stats = {};
    while (<$sock>) {
        last if /^(\.|END)/;
        /^(STAT|ITEM) (\S+)\s+([^\r\n]+)/;
        #print " slabs: $_";
        $stats->{$2} = $3;
    }
    return $stats;
}

sub mem_move_time {
    my ($sock, $move) = @_;
    print $sock "debugtime $move\r\n";
    <$sock>;
}

sub mem_get_is {
    # works on single-line values only.  no newlines in value.
    my ($sock_opts, $key, $val, $msg) = @_;
    my $opts = ref $sock_opts eq "HASH" ? $sock_opts : {};
    my $sock = ref $sock_opts eq "HASH" ? $opts->{sock} : $sock_opts;

    my $expect_flags = $opts->{flags} || 0;
    my $dval = defined $val ? "'$val'" : "<undef>";
    $msg ||= "$key == $dval";

    print $sock "get $key\r\n";
    if (! defined $val) {
        my $line = scalar <$sock>;
        if ($line =~ /^VALUE/) {
            $line .= scalar(<$sock>) . scalar(<$sock>);
        }
        Test::More::is($line, "END\r\n", $msg);
    } else {
        my $len = length($val);
        my $body = scalar(<$sock>);
        my $expected = "VALUE $key $expect_flags $len\r\n$val\r\nEND\r\n";
        if (!$body || $body =~ /^END/) {
            Test::More::is($body, $expected, $msg);
            return;
        }
        $body .= scalar(<$sock>) . scalar(<$sock>);
        Test::More::is($body, $expected, $msg);
    }
}

sub mem_gets {
    # works on single-line values only.  no newlines in value.
    my ($sock_opts, $key) = @_;
    my $opts = ref $sock_opts eq "HASH" ? $sock_opts : {};
    my $sock = ref $sock_opts eq "HASH" ? $opts->{sock} : $sock_opts;
    my $val;
    my $expect_flags = $opts->{flags} || 0;

    print $sock "gets $key\r\n";
    my $response = <$sock>;
    if ($response =~ /^END/) {
        return "NOT_FOUND";
    }
    else
    {
        $response =~ /VALUE (.*) (\d+) (\d+) (\d+)/;
        my $flags = $2;
        my $len = $3;
        my $identifier = $4;
        read $sock, $val , $len;
        # get the END
        $_ = <$sock>;
        $_ = <$sock>;

        return ($identifier,$val);
    }

}
sub mem_gets_is {
    # works on single-line values only.  no newlines in value.
    my ($sock_opts, $identifier, $key, $val, $msg) = @_;
    my $opts = ref $sock_opts eq "HASH" ? $sock_opts : {};
    my $sock = ref $sock_opts eq "HASH" ? $opts->{sock} : $sock_opts;

    my $expect_flags = $opts->{flags} || 0;
    my $dval = defined $val ? "'$val'" : "<undef>";
    $msg ||= "$key == $dval";

    print $sock "gets $key\r\n";
    if (! defined $val) {
        my $line = scalar <$sock>;
        if ($line =~ /^VALUE/) {
            $line .= scalar(<$sock>) . scalar(<$sock>);
        }
        Test::More::is($line, "END\r\n", $msg);
    } else {
        my $len = length($val);
        my $body = scalar(<$sock>);
        my $expected = "VALUE $key $expect_flags $len $identifier\r\n$val\r\nEND\r\n";
        if (!$body || $body =~ /^END/) {
            Test::More::is($body, $expected, $msg);
            return;
        }
        $body .= scalar(<$sock>) . scalar(<$sock>);
        Test::More::is($body, $expected, $msg);
    }
}

sub free_port {
    my $type = shift || "tcp";
    my $sock;
    my $port;
    while (!$sock) {
        $port = int(rand(20000)) + 30000;
        if (enabled_tls_testing()) {
            $sock = eval qq{ IO::Socket::SSL->new(LocalAddr => '127.0.0.1',
                                      LocalPort => $port,
                                      Proto     => '$type',
                                      ReuseAddr => 1,
                                      SSL_verify_mode => SSL_VERIFY_NONE);
                                      };
             die $@ if $@; # sanity check.
        } else {
            $sock = IO::Socket::INET->new(LocalAddr => '127.0.0.1',
                                      LocalPort => $port,
                                      Proto     => $type,
                                      ReuseAddr => 1);
        }
    }
    return $port;
}

sub print_help {
    my $exe = get_memcached_exe();
    my $output = `$exe -h`;
    return $output;
}

sub supports_udp {
    my $output = print_help();
    return 0 if $output =~ /^memcached 1\.1\./;
    return 1;
}

sub supports_sasl {
    my $output = print_help();
    return 1 if $output =~ /sasl/i;
    return 0;
}

sub supports_extstore {
    my $output = print_help();
    return 1 if $output =~ /ext_path/i;
    return 0;
}

sub supports_proxy {
    my $output = print_help();
    return 1 if $output =~ /proxy_config/i;
    return 0;
}

sub supports_tls {
    my $output = print_help();
    return 1 if $output =~ /enable-ssl/i;
    return 0;
}

sub supports_unix_socket {
    my $output = print_help();
    return 1 if $output =~ /unix-socket/i;
    return 0;
}

sub enabled_tls_testing {
    if ($tls_checked) {
        return 1;
    } elsif (supports_tls() && $ENV{SSL_TEST}) {
        eval "use IO::Socket::SSL";
        croak("IO::Socket::SSL not installed or failed to load, cannot run SSL tests as requested") if $@;
        $tls_checked = 1;
        return 1;
    }
}

sub supports_drop_priv {
    my $output = print_help();
    return 1 if $output =~ /no_drop_privileges/i;
    return 0;
}

sub get_memcached_exe {
    my $exe = "$builddir/memcached-debug";
    croak("memcached binary doesn't exist.  Haven't run 'make' ?\n") unless -e $exe;
    croak("memcached binary not executable\n") unless -x _;
    return $exe;
}

sub run_help {
    my $exe = get_memcached_exe();
    return system("$exe -h");
}

# -1 if the pid is actually dead.
sub is_running {
    return unless defined $_[0];
    return waitpid($_[0], WNOHANG) >= 0 ? 1 : 0;
}

sub new_memcached {
    my ($args, $passed_port) = @_;
    my $port = $passed_port;
    my $host = '127.0.0.1';
    my $ssl_enabled  = enabled_tls_testing();
    my $unix_socket_disabled  = !supports_unix_socket();
    my $use_external = 0;
    if ($ENV{T_MEMD_EXTERNAL}) {
        $use_external = $ENV{T_MEMD_EXTERNAL};
    }

    if ($ENV{T_MEMD_USE_DAEMON}) {
        my ($host, $port) = ($ENV{T_MEMD_USE_DAEMON} =~ m/^([^:]+):(\d+)$/);
        my $conn;
        if ($ssl_enabled) {
            $conn = eval qq{IO::Socket::SSL->new(PeerAddr => "$host:$port",
                                        SSL_verify_mode => SSL_VERIFY_NONE,
                                        SSL_cert_file => '$client_crt',
                                        SSL_key_file => '$client_key');
                                        };
             die $@ if $@; # sanity check.
        } else {
            $conn = IO::Socket::INET->new(PeerAddr => "$host:$port");
        }
        if ($conn) {
            return Memcached::Handle->new(conn => $conn,
                                          host => $host,
                                          port => $port);
        }
        croak("Failed to connect to specified memcached server.") unless $conn;
    }

    if ($< == 0) {
        $args .= " -u root";
    }
    $args .= " -o relaxed_privileges";

    my $udpport;
    if ($args =~ /-l (\S+)/ || (($ssl_enabled || $unix_socket_disabled) && ($args !~ /-s (\S+)/))) {
        if (!$port) {
            $port = free_port();
        }
        $udpport = free_port("udp");
        $args .= " -p $port";
        if (supports_udp() && $args !~ /-U (\S+)/) {
            $args .= " -U $udpport";
        }
        if ($ssl_enabled) {
            $args .= " -Z";
            if ($args !~ /-o ssl_chain_cert=(\S+)/) {
                $args .= " -o ssl_chain_cert=$server_crt";
            }
            if ($args !~ /-o ssl_key=(\S+)/) {
                $args .= " -o ssl_key=$server_key";
            }
        }
    } elsif ($args !~ /-s (\S+)/) {
        my $num = @unixsockets;
        my $file = "/tmp/memcachetest.$$.$num";
        if ($use_external) {
            $file = "/tmp/memcachedtest.$use_external.$num";
        }
        $args .= " -s $file";
        push(@unixsockets, $file);
    }

    my $wait_tries = 60;
    my $exe = get_memcached_exe();
    my $childpid;
    if ($use_external) {
        print STDERR "External daemon requested. Start arguments:\n$exe $args\n";
        $wait_tries = 10000;
        $childpid;
    } else {
        $childpid = fork();

        unless ($childpid) {
            my $valgrind = "";
            my $valgrind_args = "--quiet --error-exitcode=1 --exit-on-first-error=yes";
            if ($ENV{VALGRIND_ARGS}) {
                $valgrind_args = $ENV{VALGRIND_ARGS};
            }
            if ($ENV{VALGRIND_TEST}) {
                $valgrind = "valgrind $valgrind_args";
                # NOTE: caller file stuff.
                $valgrind .= " $ENV{VALGRIND_EXTRA_ARGS}";
            }
            my $cmd = "$builddir/timedrun 600 $valgrind $exe $args";
            #print STDERR "RUN: $cmd\n\n";
            exec $cmd;
            exit; # never gets here.
        }
    }

    # unix domain sockets
    if ($args =~ /-s (\S+)/) {
        # A slow/emulated/valgrinded/etc system may take longer than a second
        # for the unix socket to appear.
        my $filename = $1;
        for (1..$wait_tries) {
            my $conn = IO::Socket::UNIX->new(Peer => $filename);

            if ($conn) {
                return Memcached::Handle->new(pid  => $childpid,
                                              conn => $conn,
                                              domainsocket => $filename,
                                              host => $host,
                                              port => $port);
            } else {
                if (!$ENV{T_MEMD_EXTERNAL}) {
                    croak("Failed to connect to unix socket: memcached not running") unless is_running($childpid);
                }
                select undef, undef, undef, 0.20;
            }
        }
        croak("Failed to connect to unix domain socket: $! '$filename'") if $@;
    }

    # try to connect / find open port, only if we're not using unix domain
    # sockets

    for (1..80) {
        my $conn;
        if ($ssl_enabled) {
            $conn = eval qq{ IO::Socket::SSL->new(PeerAddr => "127.0.0.1:$port",
                                        SSL_verify_mode => SSL_VERIFY_NONE,
                                        SSL_cert_file => '$client_crt',
                                        SSL_key_file => '$client_key');
                                        };
            die $@ if $@; # sanity check.
        } else {
            $conn = IO::Socket::INET->new(PeerAddr => "127.0.0.1:$port");
        }
        if ($conn) {
            return Memcached::Handle->new(pid  => $childpid,
                                          conn => $conn,
                                          udpport => $udpport,
                                          host => $host,
                                          port => $port);
        }
        croak("Failed to connect: memcached not running") unless is_running($childpid);
        select undef, undef, undef, 0.25;
    }
    croak("Failed to startup/connect to memcached server.");
}

END {
    for (@unixsockets) {
        unlink $_;
    }
}

############################################################################
package Memcached::Handle;
use POSIX ":sys_wait_h";
sub new {
    my ($class, %params) = @_;
    return bless \%params, $class;
}

sub DESTROY {
    my $self = shift;
    if ($self->{pid}) {
        kill 2, $self->{pid};
    } else {
        print STDERR "WANT TO ISSUE KILL: 2\n";
    }
}

sub stop {
    my $self = shift;
    if ($self->{pid}) {
        kill 15, $self->{pid};
    } else {
        print STDERR "WANT TO ISSUE KILL: 15\n";
    }
}

sub graceful_stop {
    my $self = shift;
    if ($self->{pid}) {
        kill 'SIGUSR1', $self->{pid};
    } else {
        print STDERR "WANT TO ISSUE KILL: SIGUSR1\n";
    }
}

sub reload {
    my $self = shift;
    if ($self->{pid}) {
        kill 'SIGHUP', $self->{pid};
    } else {
        print STDERR "WANT TO ISSUE KILL: SIGHUP\n";
    }
}

# -1 if the pid is actually dead.
sub is_running {
    my $self = shift;
    if ($self->{pid}) {
        return waitpid($self->{pid}, WNOHANG) >= 0 ? 1 : 0;
    } else {
        print STDERR "WANTED TO CHECK IF DAEMON IS RUNNING\n";
    }
}

sub host { $_[0]{host} }
sub port { $_[0]{port} }
sub udpport { $_[0]{udpport} }

sub sock {
    my $self = shift;

    if ($self->{conn} && ($self->{domainsocket} || getpeername($self->{conn}))) {
        return $self->{conn};
    }
    return $self->new_sock;
}

sub new_sock {
    my $self = shift;
    if ($self->{domainsocket}) {
        return IO::Socket::UNIX->new(Peer => $self->{domainsocket});
    } elsif (MemcachedTest::enabled_tls_testing()) {
        my $ssl_session_cache = shift;
        my $ssl_version = shift;
        return eval qq{ IO::Socket::SSL->new(PeerAddr => "$self->{host}:$self->{port}",
                                    SSL_verify_mode => IO::Socket::SSL::SSL_VERIFY_NONE,
                                    SSL_session_cache => \$ssl_session_cache,
                                    SSL_version => '$ssl_version',
                                    SSL_cert_file => '$client_crt',
                                    SSL_key_file => '$client_key');
                                    };
    } else {
        return IO::Socket::INET->new(PeerAddr => "$self->{host}:$self->{port}");
    }
}

# needed for a specific test
sub new_nocert_tls_sock {
    my $self = shift;
    if (MemcachedTest::enabled_tls_testing()) {
        my $port = shift;
        my $ssl_version = shift;
        return eval qq{ IO::Socket::SSL->new(PeerAddr => "$self->{host}:$port",
                                    SSL_verify_mode => IO::Socket::SSL::SSL_VERIFY_NONE,
                                    SSL_version => '$ssl_version');
                                    };
    }
}

sub new_udp_sock {
    my $self = shift;
    return IO::Socket::INET->new(PeerAddr => '127.0.0.1',
                                 PeerPort => $self->{udpport},
                                 Proto    => 'udp',
                                 LocalAddr => '127.0.0.1',
                                 LocalPort => MemcachedTest::free_port('udp'),
        );

}

############################################################################
package Memcached::ProxyTest;
use IO::Socket qw(AF_INET SOCK_STREAM);
# We call out to Test::More because of some package instancing. Not completely
# sure if this is necessary anymore?
use strict;
use warnings;

sub new {
    my ($class, %p) = @_;

    die "needs servers argument"
        unless exists $p{servers} && ref($p{servers}) eq 'ARRAY';

    $p{_srv} = [];
    for my $port (@{$p{servers}}) {
        my $srv = _mock_server($port);
        Test::More::ok(defined $srv, "mock server object created");
        push(@{$p{_srv}}, $srv);
    }

    $p{_csel} = IO::Select->new();

    return bless \%p, $class;
}

sub _mock_server {
    my $port = shift;
    my $srv = IO::Socket->new(
        Domain => AF_INET,
        Type => SOCK_STREAM,
        Proto => 'tcp',
        LocalHost => '127.0.0.1',
        LocalPort => $port,
        ReusePort => 1,
        Listen => 5) || die "IO::Socket: $@";
    return $srv;
}

sub _accept_backend {
    my $srv = shift;
    my $be = $srv->accept();
    $be->autoflush(1);
    Test::More::ok(defined $be, "mock backend created");
    Test::More::like(<$be>, qr/version/, "received version command");
    my $sent = $be->send("VERSION 1.0.0-mock\r\n");
    Test::More::cmp_ok($sent, '>', 0, "wrote VERSION back to backend");

    return $be;
}

sub accept_backends {
    my $self = shift;
    $self->{_be} = [];
    for my $srv (@{$self->{_srv}}) {
        my $be = _accept_backend($srv);
        push(@{$self->{_be}}, $be);
    }
}

sub accept_backend {
    my $self = shift;
    my $idx = shift;
    $self->{_be}->[$idx] = _accept_backend($self->{_srv}->[$idx]);
}

sub close_backend {
    my $self = shift;
    my $idx = shift;
    $self->{_be}->[$idx]->close;
}

sub srv_accept_waiting {
    my $self = shift;
    my $idx = shift;
    my $wait = shift || 1;
    my $s = IO::Select->new();
    $s->add($self->{_srv}->[$idx]);
    return $s->can_read($wait);
}

sub set_c {
    my $self = shift;
    my $sel = $self->{_csel};
    if (exists $self->{_c}) {
        $sel->remove($self->{_c});
    }
    $self->{_c} = shift;
    $sel->add($self->{_c});
}

sub check_c {
    my $self = shift;
    my $c = $self->{_c};
    print $c "version\r\n";
    Test::More::like(scalar <$c>, qr/VERSION /, "version received");
}

sub wait_c {
    my ($self, $wait) = @_;
    return $self->{_csel}->can_read($wait);
}

# Remembers the last command sent to the client socket.
sub c_send {
    my $self = shift;
    my $cmd = shift;
    my $c = $self->{_c};
    print $c $cmd;
    $self->{_cmd} = $cmd;
}

# Backends can be specified as a bare number, and array reference ([0,1,2]),
# or 'all' to run against all available backends.
sub _be_list {
    my $self = shift;
    my $list = shift;
    my @l = ();
    if (ref $list eq '') {
        if (exists $self->{_be}->[$list]) {
            push(@l, $self->{_be}->[$list]);
        } elsif ($list eq 'all') {
            @l = @{$self->{_be}};
        } else {
            die "unknown argument";
        }
    } elsif (ref $list eq 'ARRAY') {
        for my $i (@$list) {
            push(@l, $self->{_be}->[$i]);
        }
    }
    return \@l;
}

# Check that the last command sent to the client arrives at the backends.
# This is a common case so this saves typing/errors while writing tests.
sub be_recv_c {
    my $self = shift;
    my $list = shift;
    my $detail = shift || 'be received data';
    die "issue a a command with c_send before calling be_recv_c" unless exists $self->{_cmd};

    my $l = $self->_be_list($list);
    my $cmd = $self->{_cmd};
    my @cmds = split(/(?<=\r\n)/, $cmd);
    for my $be (@$l) {
        for my $c (@cmds) {
            Test::More::is(scalar <$be>, $c, $detail);
        }
    }
}

sub be_recv_like {
    my $self = shift;
    my $list = shift;
    my $cmd = shift || die "must provide a command to check";
    my $detail = shift || 'be received data';

    my $l = $self->_be_list($list);
    for my $be (@$l) {
        Test::More::like(scalar <$be>, $cmd, $detail);
    }
}

# Receive a different/specific string to the backend socket.
sub be_recv {
    my $self = shift;
    my $list = shift;
    my $cmd = shift || die "must provide a command to check";
    my $detail = shift || 'be received data';

    my $l = $self->_be_list($list);
    for my $be (@$l) {
        Test::More::is(scalar <$be>, $cmd, $detail);
    }
}

# Sends a specific command to a backend socket back towards the proxy.
# Remembers the last command sent.
sub be_send {
    my $self = shift;
    my $list = shift;
    my $cmd = shift || die "must provide data to return";

    $self->{_becmd} = $cmd;
    my $l = $self->_be_list($list);
    for my $be (@$l) {
        print $be $cmd;
    }
}

# Client receives the last command sent to any backend. This is also a common
# case so we save some typing/errors by remembering this here.
sub c_recv_be {
    my $self = shift;
    my $detail = shift || 'client received be response';

    my $cmd = $self->{_becmd};
    my $c = $self->{_c};
    Test::More::is(scalar <$c>, $cmd, $detail);
}

# Client to receive an arbitrary string.
sub c_recv {
    my $self = shift;
    my $cmd = shift;
    my $detail = shift || 'client received response';

    my $c = $self->{_c};
    Test::More::is(scalar <$c>, $cmd, $detail);
}

# Clear out any remembered commands and check the client pipe is clear.
sub clear {
    my $self = shift;
    delete $self->{_becmd} if exists $self->{_becmd};
    delete $self->{_cmd} if exists $self->{_cmd};
    $self->check_c();
}

1;