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POE-Component-SpreadClient-1.003
River stage one • 1 direct dependent • 1 total dependent
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/ POE::Component::SpreadClient

NAME

POE::Component::SpreadClient - Handle Spread communications in POE

VERSION

  This document describes v1.003 of POE::Component::SpreadClient - released November 10, 2014 as part of POE-Component-SpreadClient.

SYNOPSIS

        use POE;
        POE::Component::SpreadClient->spawn( 'spread' );

        POE::Session->create(
            inline_states => {
                _start => \&_start,
                _sp_message => \&do_something,
                _sp_admin => \&do_something,
                _sp_connect => \&do_something,
                _sp_disconnect => \&do_something,
                _sp_error => \&do_something,
            }
        );

        sub _start {
                $poe_kernel->alias_set('displayer');
                $poe_kernel->post( spread => connect => 'localhost', $$ );
                $poe_kernel->post( spread => subscribe => 'chatroom' );
                $poe_kernel->post( spread => publish => 'chatroom', 'A/S/L?' );
        }

DESCRIPTION

POE::Component::SpreadClient is a POE component for talking to Spread servers.

This module should only be used with Spread 3.17.4 ( or compatible versions )

XXX Beware: this module hasn't been tested with Spread 4! XXX

METHODS

spawn

Creates a new instance of this module. Returns the session ID.

        POE::Component::Spread->spawn( 'spread' );

        # ARGS
        - The alias the component will take ( default: "SpreadClient" )

Public API

connect

Connect this POE session to the Spread server on port 4444 on localhost. Will send a _sp_error event if unable to connect; _sp_connect if successful.

        $poe_kernel->post( spread => connect => '4444@localhost' );
        $poe_kernel->post( spread => connect => '4444@localhost', 'logger' );

        # ARGS
        - The Server location
        - The private name for the Spread connection ( default: "spread-PID" )

disconnect

Forces this session to disconnect. ( DOES NOT REMOVE ALIAS => look at destroy below ) Will send a _sp_disconnect event if disconnected; _sp_error if failure.

        $poe_kernel->post( spread => disconnect );

subscribe

Subscribe to a Spread messaging group. Messages will be sent to _sp_message and join/leave/etc to _sp_admin in the registered listeners. Automatically adds the session to the registered listeners. Will send a _sp_error if unable to subscribe; _sp_admin with join message if successful.

        $poe_kernel->post( spread => subscribe => 'chatroom' );
        $poe_kernel->post( spread => subscribe => [ 'chatroom', 'testing' ] );

unsubscribe

Unsubscribes to a Spread messaging group. Does not remove the session from the listener list. Will send a _sp_error if unable to unsubscribe; _sp_admin with self_leave if successful.

        $poe_kernel->post( spread => unsubscribe => 'chatroom' );
        $poe_kernel->post( spread => unsubscribe => [ 'foobar', 'chatroom' ] );

publish

Send a string to the group(s). THIS WILL ONLY SEND STRINGS! If you need to send perl structures, use your own serializer/deserializer! Will send a _sp_error if unable to publish.

        $poe_kernel->post( spread => publish => 'chatroom', 'A/S/L?' );
        $poe_kernel->post( spread => publish => [ 'chatroom', 'stats' ], 'A/S/L?' );
        $poe_kernel->post( spread => publish => 'chatroom', 'special', 5 );
        $poe_kernel->post( spread => publish => 'chatroom', 'A/S/L?', undef, RELIABLE_MESS & SELF_DISCARD );

        # ARGS
        - The group name(s)
        - 2nd parameter ( int ) is the Spread mess_type -> application-defined ( default: 0 )
        - The 3rd parameter is the spread message type -> import them from Spread.pm ( default: SAFE_MESS )

REMEMBER about the message size limitation! Therefore max message size is 100 * 1440 =~ 140kB.

        From spread-src-3.17.4 in sess_types.h
        #define MAX_MESSAGE_BODY_LEN    (MAX_SCATTER_ELEMENTS * (MAX_PACKET_SIZE - 32)) /* 32 is sizeof(packet_header) */
        #define MAX_SCATTER_ELEMENTS    100
        #define MAX_PACKET_SIZE 1472    /*1472 = 1536-64 (of udp)*/

register

Registers the current session as a "registered listener" and will receive all events.

        $poe_kernel->post( spread => register );

unregister

Removes the current session from the "registered listeners" list.

        $poe_kernel->post( spread => unregister );

destroy

Destroys the session by removing it's alias and disconnecting if needed with _sp_disconnect

        $poe_kernel->post( spread => destroy );

EVENTS

You will receive those events in the session that registered as a listener.

_sp_connect

        sub _sp_connect : State {
                my( $priv_name, $priv_group ) = @_[ ARG0, ARG1 ];
                # We're connected!
        }

_sp_disconnect

        sub _sp_disconnect : State {
                my $priv_name = $_[ ARG0 ];
                # We're disconnected!
        }

_sp_error

        sub _sp_error : State {
                my( $priv_name, $type, $sperrno, $msg, $data ) = @_[ ARG0 .. ARG4 ];

                # Handle different kinds of errors
                if ( $type eq 'CONNECT' ) {
                        # $sperrno = Spread errno/error string, $msg = server name, $data = priv name
                } elsif ( $type eq 'PUBLISH' ) {
                        # $sperrno = Spread errno, $msg = $groups ( may be undef ), $data = $message ( may be undef )
                } elsif ( $type eq 'SUBSCRIBE' ) {
                        # $sperrno = Spread errno, $msg = $groups ( may be undef )
                } elsif ( $type eq 'UNSUBSCRIBE' ) {
                        # $sperrno = Spread errno, $msg = $groups ( may be undef )
                } elsif ( $type eq 'RECEIVE' ) {
                        # $sperrno = error string
                }
        }

_sp_message

        sub _sp_message : State {
                my( $priv_name, $sender, $groups, $mess_type, $message ) = @_[ ARG0 .. ARG4 ];

                # $mess_type is always 0 unless defined ( mess_type in Spread )
        }

_sp_admin

        sub _sp_admin : State {
                my( $priv_name, $data ) = @_[ ARG0, ARG1 ];
                # $data is hashref with several fields:
                # TYPE => string ( JOIN | LEAVE | DISCONNECT | SELF_LEAVE | TRANSITIONAL | NETWORK )
                # GROUP => string ( group name )
                # GID => [ GID1, GID2, GID3 ] ( look at Spread documentation about this! )
                # MEMBERS => arrayref of member names
                # WHO => string ( whomever left/join/discon )
                # INDEX => index of self in group list
                # MESSAGE => raw unpacked message ( needed for NETWORK's special parsing, not done! )

                # if TYPE = JOIN | LEAVE | DISCONNECT
                # GROUP, MEMBERS, WHO, GID, INDEX

                # if TYPE = SELF_LEAVE
                # GROUP

                # if TYPE = TRANSITIONAL
                # GROUP

                # if TYPE = NETWORK
                # GROUP, MEMBERS, GID, INDEX, MESSAGE
        }

SpreadClient Notes

You can enable debugging mode by doing this:

        sub POE::Component::SpreadClient::DEBUG () { 1 }
        use POE::Component::SpreadClient;

Installing Spread on Ubuntu Trusty

This documentation is really for myself, ha! As of Ubuntu 14.04 (Trusty) Spread is no longer included in the distribution nor any PPA hosts. In order to install this module I had to do the following:

        wget http://mirrors.kernel.org/ubuntu/pool/universe/s/spread/spread_3.17.4-3_amd64.deb
        wget http://mirrors.kernel.org/ubuntu/pool/universe/s/spread/libspread1_3.17.4-3_amd64.deb
        wget http://mirrors.kernel.org/ubuntu/pool/universe/s/spread/libspread1-dev_3.17.4-3_amd64.deb
        sudo dpkg -i *spread*.deb
        wget --post-data "FILE=spread-src-3.17.4.tar.gz&name=a&company=a&email=a%40a.com&comment=a&Stage=Download" http://www.spread.org/download/download_full_release_only_spread.cgi --output-document=spread-src-3.17.4.tar.gz
        tar -zxf spread-src-3.17.4.tar.gz
        cd spread-src-3.17.4
        sudo "./configure && make && make install"
        sudo nano /etc/default/spread # and set ENABLED=1
        sudo nano /etc/spread/spread.conf # and change the Spread_Segment ... localhost 127.0.0.1 to 127.0.1.1 - I think it's because of my virt-manager vlan...
        sudo /etc/init.d/spread start
        sudo cpanp i POE::Component::SpreadClient

SEE ALSO

Please see those modules/websites for more information related to this module.

SUPPORT

Perldoc

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

  perldoc POE::Component::SpreadClient

Websites

The following websites have more information about this module, and may be of help to you. As always, in addition to those websites please use your favorite search engine to discover more resources.

Email

You can email the author of this module at APOCAL at cpan.org asking for help with any problems you have.

Internet Relay Chat

You can get live help by using IRC ( Internet Relay Chat ). If you don't know what IRC is, please read this excellent guide: http://en.wikipedia.org/wiki/Internet_Relay_Chat. Please be courteous and patient when talking to us, as we might be busy or sleeping! You can join those networks/channels and get help:

  • irc.perl.org

    You can connect to the server at 'irc.perl.org' and join this channel: #perl-help then talk to this person for help: Apocalypse.

  • irc.freenode.net

    You can connect to the server at 'irc.freenode.net' and join this channel: #perl then talk to this person for help: Apocal.

  • irc.efnet.org

    You can connect to the server at 'irc.efnet.org' and join this channel: #perl then talk to this person for help: Ap0cal.

Bugs / Feature Requests

Please report any bugs or feature requests by email to bug-poe-component-spreadclient at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=POE-Component-SpreadClient. You will be automatically notified of any progress on the request by the system.

Source Code

The code is open to the world, and available for you to hack on. Please feel free to browse it and play with it, or whatever. If you want to contribute patches, please send me a diff or prod me to pull from your repository :)

https://github.com/apocalypse/perl-poe-spreadclient

  git clone https://github.com/apocalypse/perl-poe-spreadclient.git

AUTHOR

Apocalypse <APOCAL@cpan.org>

ACKNOWLEDGEMENTS

The base for this module was lifted from POE::Component::Spread by Rob Partington <perl-pcs@frottage.org>.

Thanks goes to Rob Bloodgood ( RDB ) for making sure this module still works!

This product uses software developed by Spread Concepts LLC for use in the Spread toolkit. For more information about Spread see http://www.spread.org

COPYRIGHT AND LICENSE

This software is copyright (c) 2014 by Apocalypse.

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

The full text of the license can be found in the LICENSE file included with this distribution.

DISCLAIMER OF WARRANTY

THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "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 PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.