NAME

starlight - Light and pure-Perl PSGI/Plack HTTP server with pre-forks

SYNOPSIS

$ starlight --max-workers=20 --max-reqs-per-child=100 app.psgi

$ starlight --port=80 --ipv6=1 app.psgi

$ starlight --port=443 --ssl=1 --ssl-key-file=file.key
            --ssl-cert-file=file.crt app.psgi

$ starlight --socket=/tmp/starlight.sock app.psgi

DESCRIPTION

Starlight is a standalone HTTP/1.1 server with keep-alive support. It uses pre-forking. It is a pure-Perl implementation that doesn't require any XS package.

Starlight was started as a fork of Thrall server which is a fork of Starlet server. It has almost the same code as Thrall and Starlet and it was adapted to not use any other modules than Plack.

Starlight is created for Unix-like systems but it should also work on Windows with some limitations.

OPTIONS

In addition to the options supported by plackup, starlight accepts the following options(s).

--access-log

Specifies the pathname of a file where the access log should be written. By default, in the development environment access logs will go to STDERR. See plackup. (default: none)

--daemonize

Makes the process run in the background. It doesn't work (yet) in native Windows (MSWin32). (default: 0)

-E, --env

Specifies the environment option. See plackup. (default: "deployment")

--error-log

Specify the pathname of a file where the error log should be written. This enables you to still have access to the errors when using --daemonize. (default: none)

--group

Changes the group ids or group names that the server should switch to after binding to the port. The ids or names can be separated with commas or space characters. (default: none)

-o, --host

Binds to a TCP interface. Defaults to undef, which lets most server backends bind to the any (*) interface. This option is only valid for servers which support TCP sockets.

-I

Specifies Perl library include paths, like perl's -I option. You may add multiple paths by using this option multiple times. See plackup.

--ipv6

Enables IPv6 support. The IO::Socket::IP module is required. (default: 1 if IO::Socket::IP is available or 0 otherwise)

--keepalive-timeout

Timeout for persistent connections. (default: 2)

-L, --loader

Starlet changes the default loader to Delayed to make lower consumption of the children and prevent problems with shared IO handlers. It might be set to Plack::Loader to restore the default loader.

-M

Loads the named modules before loading the app's code. You may load multiple modules by using this option multiple times. See plackup. (default: none)

--main-process-delay

The Starlight does not synchronize its processes and it requires a small delay in main process so it doesn't consume all CPU. (default: 0.1)

--max-keepalive-reqs

Max. number of requests allowed per single persistent connection. If set to one, persistent connections are disabled. (default: 1)

--max-reqs-per-child

Max. number of requests to be handled before a worker process exits. (default: 1000)

--max-workers

A number of worker processes. (default: 10)

--min-reqs-per-child

If set, randomizes the number of requests handled by a single worker process between the value and that supplied by --max-reqs-per-chlid. (default: none)

-p, --port

Binds to a TCP port. Defaults to 5000. This option is only valid for servers which support TCP sockets.

Note: default port 5000 may conflict with AirPlay server on MacOS 12 (Monterey) or later.

--pid

Specify the pid file path. Use it with -D|--daemonize option. (default: none)

-q, --quiet

Suppress the message about starting a server.

-r, --reload

Makes plackup restart the server whenever a file in your development directory changes. See plackup. (default: none)

-R, --Reload

Makes plackup restart the server whenever a file in any of the given directories changes. See plackup. (default: none)

--socket

Enables UNIX socket support. The IO::Socket::UNIX module is required. The socket file has to be not yet created. The first character @ or \0 in the socket file name means that an abstract socket address will be created. (default: none)

--spawn-interval

If set, worker processes will not be spawned more than once every given second. Also, when SIGHUP is being received, no more than one worker process will be collected every given second. This feature is useful for doing a "slow restart". (default: none)

--ssl

Enables the SSL support. The IO::Socket::SSL module is required. (default: 0)

--ssl-ca-file

Specifies the path to the SSL CA certificate file used when verification mode is enabled. (default: none)

--ssl-cert-file

Specifies the path to the SSL certificate file. (default: none)

--ssl-client-ca-file

Specifies the path to the SSL CA certificate file for client verification. (default: none)

--ssl-key-file

Specifies the path to the SSL key file. (default: none)

--ssl-verify-mode

Sets the verification mode for the peer certificate. See "SSL_verify_mode" in IO::Socket::SSL. (default: 0)

--timeout

Seconds until timeout. (default: 300)

--umask

Changes file mode creation mask. The "umask" in perlfunc is an octal number representing disabled permissions bits for newly created files. It is usually 022 when a group shouldn't have permission to write or 002 when a group should have permission to write. (default: none)

--user

Changes the user id or user name that the server process should switch to after binding to the port. The pid file, error log or unix socket also are created before changing privileges. This option is usually used if the main process is started with root privileges because of binding to the low-numbered (<1024) port. (default: none)

LIMITATIONS

Perl on Windows systems (MSWin32 and cygwin) emulates "fork" in perlfunc and "waitpid" in perlfunc functions and uses threads internally. See perlfork (MSWin32) and perlcygwin (cygwin) for details and limitations.

It might be a better option to use on this system the server with explicit threads implementation, i.e. Thrall.

For Cygwin the perl-libwin32 package is highly recommended, because of Win32::Process module which helps to terminate stalled worker processes.

BUGS

Windows

There is a problem with Perl threads implementation which occurs on Windows systems (MSWin32). Cygwin version seems to be correct.

Some requests can fail with the message:

failed to set socket to nonblocking mode:An operation was attempted on something that is not a socket.

Bad file descriptor at (eval 24) line 4.

This problem was introduced in Perl 5.16 and fixed in Perl 5.19.5.

See https://rt.perl.org/rt3/Public/Bug/Display.html?id=119003 and https://github.com/dex4er/Thrall/issues/5 for more information about this issue.

The server fails when a worker process calls "exit" in perlfunc function:

Attempt to free unreferenced scalar: SV 0x293a76c, Perl interpreter: 0x22dcc0c at lib/Plack/Handler/Starlight.pm line 140.

It means that Harakiri mode can't work and the server has to be started with --max-reqs-per-child=inf option.

See https://rt.perl.org/Public/Bug/Display.html?id=40565 and https://github.com/dex4er/Starlight/issues/1 for more information about this issue.

MacOS

MacOS High Sierra and newer shows error:

objc[12345]: +[__NSCFConstantString initialize] may have been in progress in another thread when fork() was called. objc[12345]: +[__NSCFConstantString initialize] may have been in progress in another thread when fork() was called. We cannot safely call it or ignore it in the fork() child process. Crashing instead. Set a breakpoint on objc_initializeAfterForkError to debug.

This error is caused by an added security to restrict multithreading.

To override the limitation, run export OBJC_DISABLE_INITIALIZE_FORK_SAFETY=YES before using this server.

Reporting

If you find the bug or want to implement new features, please report it at https://github.com/dex4er/Starlight/issues

The code repository is available at http://github.com/dex4er/Starlight

AUTHORS

Piotr Roszatycki <dexter@cpan.org>

Based on Thrall by: