NAME

Reflex::Role::Writable - add writable-watching behavior to a class

VERSION

This document describes version 0.100, released on April 02, 2017.

SYNOPSIS

        use Moose;

        has socket => ( is => 'rw', isa => 'FileHandle', required => 1 );

        with 'Reflex::Role::Writable' => {
                handle   => 'socket',
                cb_ready => 'on_socket_writable',
                active   => 1,
        };

        sub on_socket_writable {
                my ($self, $arg) = @_;
                print "Socket $arg->{handle} is ready for data.\n";
                $self->pause_socket_writabe();
        }

DESCRIPTION

Reflex::Role::Writable is a Moose parameterized role that adds writable-watching behavior to Reflex-based classes. In the SYNOPSIS, a filehandle named "socket" is watched for writability. The method on_socket_writable() is called when data becomes available.

TODO - Explain the difference between role-based and object-based composition.

Required Role Parameters

handle

The "handle" parameter must contain the name of the attribute that holds the handle to watch. The name indirection allows the role to generate methods that are unique to the handle. For example, a handle named "XYZ" would generates these methods by default:

        cb_ready      => "on_XYZ_writable",
        method_pause  => "pause_XYZ_writable",
        method_resume => "resume_XYZ_writable",
        method_stop   => "stop_XYZ_writable",

This naming convention allows the role to be used for more than one handle in the same class. Each handle will have its own name, and the mixed in methods associated with them will also be unique.

Optional Role Parameters

active

"active" specifies whether the Reflex::Role::Writable watcher should be enabled when it's initialized. All Reflex watchers are enabled by default. Set it to a false value, preferably 0, to initialize the watcher in an inactive or paused mode.

Writability watchers may be paused and resumed. See "method_pause" and "method_resume" for ways to override the default method names.

cb_ready

"cb_ready" names the $self method that will be called whenever "handle" has space for more data to be written. By default, it's the catenation of "on_", the "handle" name, and "_writable". A handle named "XYZ" will by default trigger on_XYZ_writable() callbacks.

        handle => "socket",  # on_socket_writable()
        handle => "XYZ",     # on_XYZ_writable()

All Reflex parameterized role callbacks are invoked with two parameters: $self and an anonymous hashref of named values specific to the callback. "cb_ready" callbacks include a single named value, "handle", that contains the filehandle from which has become ready for writing.

"handle" is the handle itself, not the handle attribute's name.

method_pause

"method_pause" sets the name of the method that may be used to pause the watcher. It is "pause_${handle}_writable" by default.

method_resume

"method_resume" may be used to resume paused writability watchers, or to activate them if they are started in an inactive state.

method_stop

"method_stop" may be used to stop readability watchers. These watchers may not be restarted once they've been stopped. If you want to pause and resume watching, see "method_pause" and "method_resume".

EXAMPLES

TODO - I'm sure there are some.

BUGS AND LIMITATIONS

You can make new bug reports, and view existing ones, through the web interface at <http://rt.cpan.org/Public/Dist/Display.html?Name=Reflex>.

AUTHOR

Rocco Caputo <rcaputo@cpan.org>

COPYRIGHT AND LICENSE

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

AVAILABILITY

The latest version of this module is available from the Comprehensive Perl Archive Network (CPAN). Visit <http://www.perl.com/CPAN/> to find a CPAN site near you, or see <https://metacpan.org/module/Reflex/>.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

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