NAME

       Event::RPC::Client - Client API to connect to Event::RPC Servers

SYNOPSIS

         use Event::RPC::Client;

         my $rpc_client = Event::RPC::Client->new (
           #-- Required arguments
           host => "localhost",
           port => 5555,

           #-- Optional arguments
           classes   => [ "Event::RPC::Test" ],
           class_map => { "Event::RPC::Test" => "My::Event::RPC::Test" },

           ssl         => 1,
           ssl_ca_file => "some/ca.crt",
           ssl_ca_path => "some/ca/dir",

           timeout     => 10,

           auth_user => "fred",
           auth_pass => Event::RPC->crypt("fred",$password),

           error_cb => sub {
             my ($client, $error) = @_;
             print "An RPC error occured: $error\n";
             $client->disconnect;
             exit;
           },
         );

         $rpc_client->connect;

         #-- And now use classes and methods to which the
         #-- server allows access via RPC, here My::TestModule
         #-- from the Event::RPC::Server manpage SYNPOSIS.
         my $obj = My::TestModule->new( data => "foobar" );
         print "obj says hello: ".$obj->hello."\n";
         $obj->set_data("new foobar");
         print "updated data: ".$obj->get_data."\n";

         $rpc_client->disconnect;

DESCRIPTION

       Use this module to write clients accessing objects and methods exported by a Event::RPC
       driven server.

       Just connect to the server over the network, optionally with SSL and user authentication,
       and then simply use the exported classes and methods like having them locally in the
       client.

       General information about the architecture of Event::RPC driven applications is collected
       in the Event::RPC manpage.

       The following documentation describes the client connection options in detail.

CONFIGURATION OPTIONS

       You need to specify at least the server hostname and TCP port to connect a Event::RPC
       server instance. If the server requires a SSL connection or user authentication you need
       to supply the corresponding options as well, otherwise connecting will fail.

       All options described here may be passed to the new() constructor of Event::RPC::Client.
       As well you may set or modify them using set_OPTION style mutators, but not after
       connect() was called!  All options may be read using get_OPTION style accessors.

   REQUIRED OPTIONS
       These are necessary to connect the server:

       server
           This is the hostname of the server running Event::RPC::Server.  Use a IP address or
           DNS name here.

       port
           This is the TCP port the server is listening to.

   NETWORK OPTIONS
       timeout
           Specify a timeout (in seconds), which is applied when connecting the server.

   CLASS IMPORT OPTION
       classes
           This is reference to a list of classes which should be imported into the client. You
           get a warning if you request a class which is not exported by the server.

           By default all server classes are imported. Use this feature if your server exports a
           huge list of classes, but your client doesn't need all of them. This saves memory in
           the client and connect performance increases.

       class_map
           Optionally you can map the class names from the server to a different name on the
           local client using the class_map hash.

           This is necessary if you like to use the same classes locally and remotely. Imported
           classes from the server are by default registered under the same name on the client,
           so this conflicts with local classes named identically.

           On the client you access the remote classes under the name assigned in the class map.
           For example with this map

             class_map => { "Event::ExecFlow::Job" => "_srv::Event::ExecFlow::Job" }

           you need to write this on the client, if you like to create an object remotely on the
           server:

             my $server_job = _srv::Event::ExecFlow::Job->new ( ... );

           and this to create an object on the client:

             my $client_job = Event::ExecFlow::Job->new ( ... );

           The server knows nothing of the renaming on client side, so you still write this on
           the server to create objects there:

             my $job = Event::ExecFlow::Job->new ( ... );

   SSL OPTIONS
       If the server accepts only SSL connections you need to enable ssl here in the client as
       well. By default the SSL connection will be established without any peer verification,
       which makes Man-in-the-Middle attacks possible. If you want to prevent that, you need to
       set either ssl_ca_file or ssl_ca_path option.

       ssl Set this option to 1 to encrypt the network connection using SSL.

       ssl_ca_file
           Path to the the Certificate Authority's certificate file (ca.crt), your server key was
           signed with.

       ssl_ca_path
           Path of a directory containing several trusted certificates with a proper index.
           Please refer to the OpenSSL documentation for details about setting up such a
           directory.

   AUTHENTICATION OPTIONS
       If the server requires user authentication you need to set the following options:

       auth_user
           A valid username.

       auth_pass
           The corresponding password, encrypted using Perl's crypt() function, using the
           username as the salt.

           Event::RPC has a convenience function for generating such a crypted password, although
           it's currently just a wrapper around Perl's builtin crypt() function, but probably
           this changes someday, so better use this method:

             $crypted_pass = Event::RPC->crypt($user, $pass);

       If the passed credentials are invalid the Event::RPC::Client->connect() method throws a
       correspondent exception.

   ERROR HANDLING
       Any exceptions thrown on the server during execution of a remote method will result in a
       corresponding exception on the client. So you can use normal exception handling with eval
       {} when executing remote methods.

       But besides this the network connection between your client and the server may break at
       any time. This raises an exception as well, but you can override this behaviour with the
       following attribute:

       error_cb
           This subroutine is called if any error occurs in the network communication between the
           client and the server. The actual Event::RPC::Client object and an error string are
           passed as arguments.

           This is no generic exception handler for exceptions thrown from the executed methods
           on the server! If you like to catch such exceptions you need to put an eval {} around
           your method calls, as you would do for local method calls.

           If you don't specify an error_cb an exception is thrown instead.

METHODS

       $rpc_client->connect
           This establishes the configured connection to the server. An exception is thrown if
           something goes wrong, e.g. server not available, credentials are invalid or something
           like this.

       $rpc_client->disconnect
           Closes the connection to the server. You may omit explicit disconnecting since it's
           done automatically once the Event::RPC::Client object gets destroyed.

READY ONLY ATTRIBUTES

       $rpc_client->get_server_version
           Returns the Event::RPC version number of the server after connecting.

       $rpc_client->get_server_protocol
           Returns the Event::RPC protocol number of the server after connecting.

       $rpc_client->get_client_version
           Returns the Event::RPC version number of the client.

       $rpc_client->get_client_protocol
           Returns the Event::RPC protocol number of the client.

AUTHORS

         Joern 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.