NAME

LWP::Protocol::AnyEvent::http - Event loop friendly HTTP/HTTPS/SOCKS backend for LWP

VERSION

Version 1.14.0

SYNOPSIS

# Make HTTP and HTTPS requests friendly to event loops.
use LWP::Protocol::AnyEvent::http;

# Or LWP::Simple, WWW::Mechanize, etc
use LWP::UserAgent;

# A reason to want LWP friendly to event loops.
use Coro qw( async );

for my $url (@urls) {
    async {
        my $ua = LWP::UserAgent->new();
        $ua->protocols_allowed([qw( http https )]);  # The only protocols made safe.

        process( $ua->get($url) );
    };
}



# Using a worker pool model to fetch web pages in parallel.

use Coro                          qw( async );
use Coro::Channel                 qw( );
use LWP::Protocol::AnyEvent::http qw( );
use LWP::UserAgent                qw( );

my $num_workers = 10;

my $q = Coro::Channel->new();

my @threads;
for (1..$num_workers) {
    push @threads, async {
        my $ua = LWP::UserAgent->new();
        $ua->protocols_allowed([qw( http https )]);

        while (my $url = $q->get()) {
            handle_response($ua->get($url));
        }
    }
}

while (my $url = get_next_url()) {
    $q->put($url);
}

$q->shutdown();
$_->join() for @threads;

DESCRIPTION

LWP performs a number of blocking calls when trying to process requests. This makes it unfriendly to event-driven systems and cooperative multitasking system such as Coro.

This module makes LWP more friendly to these systems by plugging in an HTTP, HTTPS and SOCKS protocol implementor powered by AnyEvent and AnyEvent::HTTP.

In short, it allows AnyEvent callbacks and Coro threads to execute when LWP is blocked. (Please let me know at <ikegami@adaelis.com> what other system this helps so I can add tests and add a mention.)

All LWP features and configuration options should still be available when using this module.

SUPPORTED PROTOCOLS

The following protocols are supported:

• https: request and proxy

• http: request and proxy

• socks: alias for socks5

• socks5: proxy only

• socks4a: proxy only

• socks4: proxy only

SSL SUPPORT

Only the following ssl_opts are currently supported:

• verify_hostname

• SSL_verify_mode

  Only partially supported. Unspecified or VERIFY_NONE disables verification, anything else enables it.

• SSL_verifycn_scheme

  Only www is supported. Any other value is ignored.

• SSL_ca_file

• SSL_ca_path

• SSL_cert_file

• SSL_cert

• SSL_key_file

• SSL_key

As with LWP::Protocol::https, if hostname verification is requested by LWP::UserAgent's ssl_opts, and neither SSL_ca_file nor SSL_ca_path is set, then SSL_ca_file is implied to be the one provided by Mozilla::CA.

The maintainer will be happy to add support for additional options.

SEE ALSO

• LWP::Protocol::Coro::http

  An earlier implementation of this module that requires Coro. These two modules are developed in parallel.

• Coro

  An excellent cooperative multitasking library assisted by this module.

• AnyEvent, AnyEvent::HTTP, AnyEvent::HTTP::Socks

  Powers this module.

• LWP::Simple, LWP::UserAgent, WWW::Mechanize

  Affected by this module.

• Coro::LWP

  An alternative to this module for users of Coro. Intrusive, which results in problems in some unrelated code. Doesn't support HTTPS. Supports FTP and NTTP.

• AnyEvent::HTTP::LWP::UserAgent

  An alternative to this module that attempts to provide the same interface as LWP::UserAgent, but falls short in many ways. Unlike AnyEvent::HTTP::LWP::UserAgent, this module only replaces the back end of LWP::UserAgent, offering a much more faithful experience.

BUGS

Please report any bugs or feature requests to bug-LWP-Protocol-AnyEvent-http at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=LWP-Protocol-AnyEvent-http. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc LWP::Protocol::AnyEvent::http

You can also look for information at:

• Search CPAN

  http://search.cpan.org/dist/LWP-Protocol-AnyEvent-http

• RT: CPAN's request tracker

  http://rt.cpan.org/NoAuth/Bugs.html?Dist=LWP-Protocol-AnyEvent-http

• AnnoCPAN: Annotated CPAN documentation

  http://annocpan.org/dist/LWP-Protocol-AnyEvent-http

• CPAN Ratings

  http://cpanratings.perl.org/d/LWP-Protocol-AnyEvent-http

AUTHORS

Eric Brine, <ikegami@adaelis.com>, Maintainer

Max Maischein, <corion@cpan.org>

Graham Barr, <gbarr@pobox.com>

COPYRIGHT & LICENSE

No rights reserved.

The author has dedicated the work to the Commons by waiving all of his or her rights to the work worldwide under copyright law and all related or neighboring legal rights he or she had in the work, to the extent allowable by law.

Works under CC0 do not require attribution. When citing the work, you should not imply endorsement by the author.

cpanm LWP::Protocol::AnyEvent::http

perl -MCPAN -e shell
install LWP::Protocol::AnyEvent::http