Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
Event::RPC(3)	      User Contributed Perl Documentation	 Event::RPC(3)

NAME
       Event::RPC - Event based	transparent Client/Server RPC framework

SYNOPSIS
	 #-- Server Code
	 use Event::RPC::Server;
	 use My::TestModule;
	 my $server = Event::RPC::Server->new (
	     port    =>	5555,
	     classes =>	{ "My::TestModule" => {	... } },
	 );
	 $server->start;

	 ----------------------------------------------------------

	 #-- Client Code
	 use Event::RPC::Client;
	 my $client = Event::RPC::Client->new (
	     server   => "localhost",
	     port     => 5555,
	 );
	 $client->connect;

	 #-- Call methods of My::TestModule on the server
	 my $obj = My::TestModule->new ( foo =>	"bar" );
	 my $foo = $obj->get_foo;

ABSTRACT
       Event::RPC supports you in developing Event based networking
       client/server applications with transparent object/method access	from
       the client to the server. Network communication is optionally encrypted
       using IO::Socket::SSL. Several event loop managers are supported	due to
       an extensible API. Currently Event, Glib	and AnyEvent are implemented.
       The latter lets you use nearly every event loop implementation
       available for Perl. AnyEvent was	invented after Event::RPC was created
       and thus	Event::RPC started using it's own abstraction model.

DESCRIPTION
       Event::RPC consists of a	server and a client library. The server
       exports a list of classes and methods, which are	allowed	to be called
       over the	network. More specific it acts as a proxy for objects created
       on the server side (on demand of	the connected clients) which handles
       client side methods calls with transport	of method arguments and	return
       values.

       The object proxy	handles	refcounting and	destruction of objects created
       by clients properly. Objects as method parameters and return values are
       handled as well (although with some limitations,	see below).

       For the client the whole	thing is totally transparent - once connected
       to the server it	doesn't	know whether it	calls methods on local or
       remote objects.

       Also the	methods	on the server newer know whether they are called
       locally or from a connected client. Your	application logic is not
       affected	by Event::RPC at all, at least if it has a rudimentary clean
       OO design.

       For details on implementing servers and clients please refer to the man
       pages of	Event::RPC::Server and Event::RPC::Client.

REQUIREMENTS
       Event::RPC needs	either one of the following modules on the server
       (they're	not necessary on the client):

	 Event
	 Glib
	 AnyEvent

       They're needed for event	handling resp. mainloop	implementation.	 If
       you like	to use SSL encryption you need to install

	 IO::Socket::SSL

       As well Event::RPC makes	heavy use of the

	 Storable

       module, which is	part of	the Perl standard library. It's	important that
       both client and server use exactly the same version of the Storable
       module! Otherwise Event::RPC client/server communication	will fail
       badly.

INSTALLATION
       You get the latest installation tarballs	and online documentation at
       this location:

	 http://www.exit1.org/Event-RPC/

       If your system meets the	requirements mentioned above, installation is
       just:

	 perl Makefile.PL
	 make test
	 make install

       To test a specific Event	loop implementation, export the	variable
       EVENT_RPC_LOOP:

	 export	EVENT_RPC_LOOP=Event::RPC::Loop::Glib
	 make test

       Otherwise Event::RPC will fallback to the most appropriate module
       installed on your system.

EXAMPLES
       The tarball includes an examples/ directory which contains two
       programs:

	 server.pl
	 client.pl

       Just execute them with --help to	get the	usage. They do some very
       simple communication but	are good to test your setup, in	particular in
       a mixed environment.

LIMITATIONS
       Although	the classes and	objects	on the server are accessed
       transparently by	the client there are some limitations should be	aware
       of. With	a clean	object oriented	design these should be no problem in
       real applications:

   Direct object data manipulation is forbidden
       All objects reside on the server	and they keep there! The client	just
       has specially wrapped proxy objects, which trigger the necessary	magic
       to access the object's methods on the server. Complete objects are
       never transferred from the server to the	client,	so something like this
       does not	work:

	 $object->{data} = "changed data";

       (assuming $object is a hash ref on the server).

       Only method calls are transferred to the	server,	so even	for "simple"
       data manipulation a method call is necessary:

	 $object->set_data ("changed data");

       As well for reading an object attribute.	Accessing a hash key will
       fail:

	 my $data = $object->{data};

       Instead call a method which returns the 'data' member:

	 my $data = $object->get_data;

   Methods may exchange	objects, but not in a too complex structure
       Event::RPC handles methods which	return objects.	The only requirement
       is that they are	declared as a Object returner on the server (refer to
       Event::RPC::Server for details),	but not	if the object is hidden	inside
       a deep complex data structure.

       An array	or hash	ref of objects is Ok, but not more. This would require
       to much expensive runtime data inspection.

       Object receiving	parameters are more restrictive, since even hiding
       them inside one array or	hash ref is not	allowed.  They must be passed
       as a direkt argument of the method subroutine.

AUTHORS
	 JA<paragraph>rn Reder <joern at zyn dot de>

COPYRIGHT AND LICENSE
       Copyright (C) 2002-2006 by Joern	Reder, All Rights Reserved.

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

POD ERRORS
       Hey! The	above document had some	coding errors, which are explained
       below:

       Around line 166:
	   Non-ASCII character seen before =encoding in	'JA<paragraph>rn'.
	   Assuming CP1252

perl v5.32.0			  2013-02-02			 Event::RPC(3)

NAME | SYNOPSIS | ABSTRACT | DESCRIPTION | REQUIREMENTS | INSTALLATION | EXAMPLES | LIMITATIONS | AUTHORS | COPYRIGHT AND LICENSE | POD ERRORS

Want to link to this manual page? Use this URL:
<https://www.freebsd.org/cgi/man.cgi?query=Event::RPC&sektion=3&manpath=FreeBSD+12.2-RELEASE+and+Ports>

home | help