NAME

    thrall - a simple PSGI/Plack HTTP server that uses threads

SYNOPSIS

        $ thrall --max-workers=20 --max-reqs-per-child=100 app.psgi
    
        $ thrall --port=80 --ipv6=1 app.psgi
    
        $ thrall --port=443 --ssl=1 --ssl-key-file=file.key --ssl-cert-file=file.crt app.psgi
    
        $ thrall --socket=/tmp/thrall.sock app.psgi

DESCRIPTION

    Thrall is a standalone HTTP/1.1 server with keep-alive support. It uses
    threads instead pre-forking, so it works correctly on Windows. It is a
    pure-Perl implementation that doesn't require any XS package.

    Thrall was started as a fork of Starlet server. It has almost the same
    code as Starlet and it was adapted to use threads instead fork().

SEE ALSO

    Starlight, Starlet, Starman

LIMITATIONS

    See "BUGS AND LIMITATIONS" in threads and "Thread-Safety of System
    Libraries" in perlthrtut to read about limitations for PSGI
    applications started with Thrall and check if you encountered a known
    problem.

    Especially, PSGI applications should avoid: changing the current
    working directory, catching signals, and starting new processes.
    Environment variables might (Linux, Unix) or might not (Windows) be
    shared between threads.

    Thrall is very slow on the first request for each thread. It is because
    spawning new threads is slow in Perl itself. Thrall is very fast on
    another request and generally is faster than any implementation which
    uses fork.

BUGS

    There is a problem with Perl threads implementation which occurs on
    Windows. 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.

    or

      Bad file descriptor at (eval 24) line 4.

    Cygwin version seems to be correct.

    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.

 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/Thrall/issues

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

AUTHORS

    Piotr Roszatycki <dexter@cpan.org>

    Based on Starlet by:

    Kazuho Oku

    miyagawa

    kazeburo

    Some code based on Plack:

    Tatsuhiko Miyagawa

    Some code based on Net::Server::Daemonize:

    Jeremy Howard <j+daemonize@howard.fm>

    Paul Seamons <paul@seamons.com>

LICENSE

    Copyright (c) 2013-2017, 2023 Piotr Roszatycki <dexter@cpan.org>.

    This is free software; you can redistribute it and/or modify it under
    the same terms as perl itself.

    See http://dev.perl.org/licenses/artistic.html