POE::Component::IKC::ClientLite.3pm

Langue: en

Version: 2008-01-16 (ubuntu - 08/07/09)

Section: 3 (Bibliothèques de fonctions)

NAME

POE::Component::IKC::ClientLite - Small client for IKC

SYNOPSIS

     use POE::Component::IKC::ClientLite;
 
     $poe=create_ikc_client(port=>1337);
     die POE::Component::IKC::ClientLite::error() unless $poe;
 
     $poe->post("Session/event", $param)
         or die $poe->error;
     
     # bad way of getting a return value
     my $foo=$poe->call("Session/other_event", $param)
         or die $poe->error;
 
     # better way of getting a return value
     my $ret=$poe->post_respond("Session/other_event", $param)
         or die $poe->error;
 
     # make sure connectin is aliave
     $poe->ping() 
         or $poe->disconnect;
 
 

DESCRIPTION

ClientLite is a small, pure-Perl IKC client implementation. It is very basic because it is intented to be used in places where POE wouldn't fit, like mod_perl.

It handles automatic reconnection. When you post an event, ClientLite will try to send the packet over the wire. If this fails, it tries to reconnect. If it can't it returns an error. If it can, it will send he packet again. If *this* fails, well, tough luck.

METHODS

create_ikc_client

Creates a new PoCo::IKC::ClientLite object. Parameters are supposedly compatible with PoCo::IKC::Client, but unix sockets aren't handled yet... What's more, there are 3 additional parameters:
block_size
Size, in octets (8 bit bytes), of each block that is read from the socket at a time. Defaults to 65535.
timeout
Time, in seconds, that "call" and "post_respond" will wait for a response. Defaults to 30 seconds.
connect_timeout
Time, in seconds, to wait for a phase of the connection negotiation to complete. Defaults to "timeout". There are 4 phases of negotiation, so a the default "connect_timeout" of 30 seconds means it could potentialy take 2 minutes to connect.

connect

     $poe->connect or die $poe->error;
 
 

Connects to the remote kernel if we aren't already. You can use this method to make sure that the connection is open before trying anything.

Returns true if connection was successful, false if not. You can check ``error'' to see what the problem was.

disconnect

Disconnects from remote IKC server.

error

     my $error=POE::Component::IKC::ClientLite::error();
     $error=$poe->error();
 
 

Returns last error. Can be called as a object method, or as a global function.

post

     $poe->post($specifier, $data);
 
 

Posts the event specified by $specifier to the remote kernel. $data is any parameters you want to send along with the event. It will return 1 on success (ie, data could be sent... not that the event was received) and undef() if we couldn't connect or reconnect to remote kernel.

post_respond

     my $back=$poe->post_respond($specifier, $data);
 
 

Posts the event specified by $specifier to the remote kernel. $data is any parameters you want to send along with the event. It waits until the remote kernel sends a message back and returns it's payload. Waiting timesout after whatever you value you gave to POE::Component::IKC::Client->spawn.

Events on the far side have to be aware of post_respond. In particular, ARG0 is not $data as you would expect, but an arrayref that contains $data followed by a specifier that should be used to post back.

     sub my_event
     {
         my($kernel, $heap, $args)=@_[KERNEL, HEAP, ARG0];
         my $p=$args->[0];
         $heap->{rsvp}=$args->[1];
         # .... do lotsa stuff here
     }
 
     # eventually, we are finished
     sub finished
     {
         my($kernel, $heap, $return)=@_[KERNEL, HEAP, ARG0];
         $kernel->post(IKC=>'post', $heap->{rsvp}, $return);
     }
 
 

call

     my $back=$poe->call($specifier, $data);
 
 

This is the bad way to get information back from the a remote event. Follows the expected semantics from standard POE. It works better then post_respond, however, because it doesn't require you to change your interface or write a wrapper.

ping

     unless($poe->ping) {
         # connection is down!  connection is down!
     }
 
 

Find out if we are still connected to the remote kernel. This method will NOT try to reconnect to the remote server

name

Returns our local name. This is what the remote kernel thinks we are called. I can't really say this is the local kernel name, because, well, this isn't really a kernel. But hey.

AUTHOR

Philip Gwyn, <perl-ikc at pied.nu> Copyright 1999-2008 by Philip Gwyn. All rights reserved.

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

See <http://www.perl.com/language/misc/Artistic.html>

SEE ALSO

POE, POE::Component::IKC