package Starlet::Server;
use strict;
use warnings;
use Carp ();
use Plack;
use Plack::HTTPParser qw( parse_http_request );
use IO::Socket::INET;
use HTTP::Date;
use HTTP::Status;
use List::Util qw(max sum);
use Plack::Util;
use Plack::TempBuffer;
use POSIX qw(EINTR EAGAIN EWOULDBLOCK);
use Socket qw(IPPROTO_TCP TCP_NODELAY);
use Try::Tiny;
use Time::HiRes qw(time);
use constant MAX_REQUEST_SIZE => 131072;
use constant MSWin32 => $^O eq 'MSWin32';
my $null_io = do { open my $io, "<", \""; $io };
sub new {
my($class, %args) = @_;
my $self = bless {
host => $args{host} || 0,
port => $args{port} || 8080,
timeout => $args{timeout} || 300,
keepalive_timeout => $args{keepalive_timeout} || 2,
max_keepalive_reqs => $args{max_keepalive_reqs} || 1,
server_software => $args{server_software} || $class,
server_ready => $args{server_ready} || sub {},
min_reqs_per_child => (
defined $args{min_reqs_per_child}
? $args{min_reqs_per_child} : undef,
),
max_reqs_per_child => (
$args{max_reqs_per_child} || $args{max_requests} || 100,
),
spawn_interval => $args{spawn_interval} || 0,
err_respawn_interval => (
defined $args{err_respawn_interval}
? $args{err_respawn_interval} : undef,
),
is_multiprocess => Plack::Util::FALSE,
_using_defer_accept => undef,
}, $class;
if ($args{max_workers} && $args{max_workers} > 1) {
Carp::carp(
"Preforking in $class is deprecated. Falling back to the non-forking mode. ",
"If you need preforking, use Starman or Starlet instead and run like `plackup -s Starlet`",
);
}
$self;
}
sub run {
my($self, $app) = @_;
$self->setup_listener();
$self->accept_loop($app);
}
sub setup_listener {
my $self = shift;
$self->{listen_sock} ||= IO::Socket::INET->new(
Listen => SOMAXCONN,
LocalPort => $self->{port},
LocalAddr => $self->{host},
Proto => 'tcp',
ReuseAddr => 1,
) or die "failed to listen to port $self->{port}:$!";
# set defer accept
if ($^O eq 'linux') {
setsockopt($self->{listen_sock}, IPPROTO_TCP, 9, 1)
and $self->{_using_defer_accept} = 1;
}
$self->{server_ready}->($self);
}
sub accept_loop {
# TODO handle $max_reqs_per_child
my($self, $app, $max_reqs_per_child) = @_;
my $proc_req_count = 0;
while (! defined $max_reqs_per_child || $proc_req_count < $max_reqs_per_child) {
local $SIG{PIPE} = 'IGNORE';
if (my $conn = $self->{listen_sock}->accept) {
$self->{_is_deferred_accept} = $self->{_using_defer_accept};
$conn->blocking(0)
or die "failed to set socket to nonblocking mode:$!";
$conn->setsockopt(IPPROTO_TCP, TCP_NODELAY, 1)
or die "setsockopt(TCP_NODELAY) failed:$!";
my $req_count = 0;
while (1) {
++$req_count;
++$proc_req_count;
my $env = {
SERVER_PORT => $self->{port},
SERVER_NAME => $self->{host},
SCRIPT_NAME => '',
REMOTE_ADDR => $conn->peerhost,
REMOTE_PORT => $conn->peerport,
'psgi.version' => [ 1, 1 ],
'psgi.errors' => *STDERR,
'psgi.url_scheme' => 'http',
'psgi.run_once' => Plack::Util::FALSE,
'psgi.multithread' => Plack::Util::FALSE,
'psgi.multiprocess' => $self->{is_multiprocess},
'psgi.streaming' => Plack::Util::TRUE,
'psgi.nonblocking' => Plack::Util::FALSE,
'psgix.input.buffered' => Plack::Util::TRUE,
'psgix.io' => $conn,
};
# no need to take care of pipelining since this module is a HTTP/1.0 server
my $may_keepalive = $req_count < $self->{max_keepalive_reqs};
if ($may_keepalive && $max_reqs_per_child && $proc_req_count >= $max_reqs_per_child) {
$may_keepalive = undef;
}
$self->handle_connection($env, $conn, $app, $may_keepalive, $req_count != 1)
or last;
# TODO add special cases for clients with broken keep-alive support, as well as disabling keep-alive for HTTP/1.0 proxies
}
$conn->close;
}
}
}
sub handle_connection {
my($self, $env, $conn, $app, $use_keepalive, $is_keepalive) = @_;
my $buf = '';
my $res = [ 400, [ 'Content-Type' => 'text/plain' ], [ 'Bad Request' ] ];
my $can_exit = 1;
my $term_received = 0;
local $SIG{TERM} = sub {
$term_received++;
exit 0
if ($is_keepalive && $can_exit) || $term_received > 1;
# warn "server termination delayed while handling current HTTP request";
};
while (1) {
my $rlen = $self->read_timeout(
$conn, \$buf, MAX_REQUEST_SIZE - length($buf), length($buf),
$is_keepalive ? $self->{keepalive_timeout} : $self->{timeout},
) or return;
undef $can_exit;
my $reqlen = parse_http_request($buf, $env);
if ($reqlen >= 0) {
# handle request
if ($use_keepalive) {
if (my $c = $env->{HTTP_CONNECTION}) {
$use_keepalive = undef
unless $c =~ /^\s*keep-alive\s*/i;
} else {
$use_keepalive = undef;
}
}
$buf = substr $buf, $reqlen;
if (my $cl = $env->{CONTENT_LENGTH}) {
my $buffer = Plack::TempBuffer->new($cl);
while ($cl > 0) {
my $chunk;
if (length $buf) {
$chunk = $buf;
$buf = '';
} else {
$self->read_timeout(
$conn, \$chunk, $cl, 0, $self->{timeout})
or return;
}
$buffer->print($chunk);
$cl -= length $chunk;
}
$env->{'psgi.input'} = $buffer->rewind;
} else {
$env->{'psgi.input'} = $null_io;
}
$res = Plack::Util::run_app $app, $env;
last;
}
if ($reqlen == -2) {
# request is incomplete, do nothing
} elsif ($reqlen == -1) {
# error, close conn
last;
}
}
if (ref $res eq 'ARRAY') {
$self->_handle_response($res, $conn, \$use_keepalive);
} elsif (ref $res eq 'CODE') {
$res->(sub {
$self->_handle_response($_[0], $conn, \$use_keepalive);
});
} else {
die "Bad response $res";
}
if ($term_received) {
exit 0;
}
return $use_keepalive;
}
sub _handle_response {
my($self, $res, $conn, $use_keepalive_r) = @_;
my $status_code = $res->[0];
my $headers = $res->[1];
my $body = $res->[2];
my @lines;
my %send_headers;
for (my $i = 0; $i < @$headers; $i += 2) {
my $k = $headers->[$i];
my $v = $headers->[$i + 1];
my $lck = lc $k;
if ($lck eq 'connection') {
$$use_keepalive_r = undef
if $$use_keepalive_r && lc $v ne 'keep-alive';
} else {
push @lines, "$k: $v\015\012";
$send_headers{$lck} = $v;
}
}
if ( ! exists $send_headers{server} ) {
unshift @lines, "Server: $self->{server_software}\015\012";
}
if ( ! exists $send_headers{date} ) {
unshift @lines, "Date: @{[HTTP::Date::time2str()]}\015\012";
}
# try to set content-length when keepalive can be used, or disable it
if ($$use_keepalive_r) {
if (defined $send_headers{'content-length'}
|| defined $send_headers{'transfer-encoding'}) {
# ok
} elsif (! Plack::Util::status_with_no_entity_body($status_code)
&& defined(my $cl = Plack::Util::content_length($body))) {
push @lines, "Content-Length: $cl\015\012";
} else {
$$use_keepalive_r = undef
}
push @lines, "Connection: keep-alive\015\012"
if $$use_keepalive_r;
}
unshift @lines, "HTTP/1.0 $status_code @{[ HTTP::Status::status_message($status_code) ]}\015\012";
push @lines, "\015\012";
if (defined $body && ref $body eq 'ARRAY' && @$body == 1
&& length $body->[0] < 1024) {
# combine response header and small request body
$self->write_all(
$conn, join('', @lines, $body->[0]), $self->{timeout},
);
return;
}
$self->write_all($conn, join('', @lines), $self->{timeout})
or return;
if (defined $body) {
my $failed;
Plack::Util::foreach(
$body,
sub {
unless ($failed) {
$self->write_all($conn, $_[0], $self->{timeout})
or $failed = 1;
}
},
);
} else {
return Plack::Util::inline_object
write => sub { $self->write_all($conn, $_[0], $self->{timeout}) },
close => sub { };
}
}
# returns value returned by $cb, or undef on timeout or network error
sub do_io {
my ($self, $is_write, $sock, $buf, $len, $off, $timeout) = @_;
my $ret;
unless ($is_write || delete $self->{_is_deferred_accept}) {
goto DO_SELECT;
}
DO_READWRITE:
# try to do the IO
if ($is_write) {
$ret = syswrite $sock, $buf, $len, $off
and return $ret;
} else {
$ret = sysread $sock, $$buf, $len, $off
and return $ret;
}
unless ((! defined($ret)
&& ($! == EINTR || $! == EAGAIN || $! == EWOULDBLOCK))) {
return;
}
# wait for data
DO_SELECT:
while (1) {
my ($rfd, $wfd);
my $efd = '';
vec($efd, fileno($sock), 1) = 1;
if ($is_write) {
($rfd, $wfd) = ('', $efd);
} else {
($rfd, $wfd) = ($efd, '');
}
my $start_at = time;
my $nfound = select($rfd, $wfd, $efd, $timeout);
$timeout -= (time - $start_at);
last if $nfound;
return if $timeout <= 0;
}
goto DO_READWRITE;
}
# returns (positive) number of bytes read, or undef if the socket is to be closed
sub read_timeout {
my ($self, $sock, $buf, $len, $off, $timeout) = @_;
$self->do_io(undef, $sock, $buf, $len, $off, $timeout);
}
# returns (positive) number of bytes written, or undef if the socket is to be closed
sub write_timeout {
my ($self, $sock, $buf, $len, $off, $timeout) = @_;
$self->do_io(1, $sock, $buf, $len, $off, $timeout);
}
# writes all data in buf and returns number of bytes written or undef if failed
sub write_all {
my ($self, $sock, $buf, $timeout) = @_;
my $off = 0;
while (my $len = length($buf) - $off) {
my $ret = $self->write_timeout($sock, $buf, $len, $off, $timeout)
or return;
$off += $ret;
}
return length $buf;
}
1;