Games::FrozenBubble::NetDiscover(3pm)			User Contributed Perl Documentation		     Games::FrozenBubble::NetDiscover(3pm)

Frozen-Bubble
       Copyright X 2010 The Frozen-Bubble Team

       This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2, as
       published by the Free Software Foundation.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation,
       Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

NAME

       Games::FrozenBubble::NetDiscover - high performance server discovery plugin for frozen bubble

SYNOPSIS

	   my $discover = Games::FrozenBubble::NetDiscover->new(
	       { host => "1.2.3.4", port => 1511 },
	       { host => "5.6.7.8", port => 1512 }, ...);
	   while($discover->pending()) {
	       my @servers = $discover->found();
	       for(my $server = 0; $server < @servers; $server++) {
		   printf("%02i: ip %s ping %i
",
		       $server, $servers[$server]{ip}, $servers[$server]{ping});
	       }
	       $discover->work(0.1); # sit in a select loop for 100ms

	       # update your screen, and all of that stuff, here.
	   }

DESCRIPTION

       Games::FrozenBubble::NetDiscover checks a list of servers, finding their versions, ping times, and number of current clients.  It uses
       nonblocking IO and select, to connect to multiple servers in parallel, thus reducing the total amount of time elapsed.  This, in turn,
       allows the user to begin playing frozen bubble more quickly. :)

       This module is designed to be called from a GUI loop.  It has to spend sit in a select loop for most of its life in order to get accurate
       ping times, but it will return back to your loop at intervals you specify, so you can check for keystrokes and refresh the screen and so
       forth.

       In order to get consistent results on slow dialup links, this module will only attempt to connect to one server per each 200ms.	This means
       for 18 servers that there are 3.4 seconds of extra guaranteed lag, but it also means packets from multiple servers are less likely to bump
       into eachother in the queue, so ping reply times will be more reliable.

       In the source script, there are two configuration parameters: $number_of_pings and $time_between_connections.  These are set to 2 and 0.2,
       respectively.  These two parameters will determine the amount of bandwidth used, and the amount of time taken before the user can select a
       server.	Assuming the user's internet connection can handle the traffic without extra latency from queueing or retransmissions, the worst
       case latency will be, in seconds:

	   N*L + T*(S-1)

       where

	   N = $number_of_pings
	   L = the roundtrip time of the slowest server in the list, in seconds
	   T = $time_between_connections
	   S = the number of servers in the list

CONSTRUCTOR

	   ...->new ({host => "server1", port => port}, {host => "server2", port => port}, ...)

       Takes a list of servers as arguments.  Each server argument should be a hash reference, consisting of {host => host, port => port}.
       Returns a Games::FrozenBubble::NetDiscover object, which can be used within a GUI loop to discover all of your servers.

       The host string should ideally be an IP address.  A hostname string should work too, but DNS lookups will introduce extra, unpredictable
       latency later on.

METHODS

       These methods define the public API for instances of this class.

   found
       Returns a list of 0 or more servers found.  Each return value is a hash reference, containing the following keys:

	   host: the IP address of the server
	   port: the TCP port of the server
	   pingtimes: array reference, contains the actual result times of 4 pings
	   ping: the average roundtrip latency of the server, in ms
	   freenicks: the list of players connected
	   freegames: the list of open games (not yet started)
	   free: the number of idle clients connected to this server
	   games: the number of clients connected to this server, who are playing games
	   playing: the list of players in games
	   geolocs: the geolocations of players in games
	   name: the self-proclaimed "name" reported by the server
	   language: the preferred language reported by the server

   pending
       Returns non-zero if we are still waiting for a response from one or more servers; returns 0 if processing is complete.

   work(seconds)
       Enters the main loop of this module.  This method requires one argument, a numeric count of seconds to work for.  This is expected to be a
       floating point decimal, for sub-second precision.  Returns the number of servers pending, just like the pending method does.

INTERNAL METHODS

       These methods are only meant to be called from within the module.  They are subject to change without notice.

   try_connect
       Attempts to connect to a server.  Moves the first "not_started" server to the "pending" list, and creates a non-blocking IO::Socket::INET
       object for it.  Updates the begin_time timestamp, to determine when the next server should be connected.

   server_sm(connection_number)
       Implements a simple state machine.  Called with an index into the pending array, to indicate that data is available for reading from this
       server.

   give_up_on(connection_number, reason)
       Called if select reports a socket as has_exception.  Also called if the server has a bogus version, times out, or we can't parse the IP
       address or something.  Removes the entry from further processing, and emits an error message on stderr.

EXPORT

       None.

BUGS

       implement some sort of timeout, for servers which don't respond within 5 seconds.

AUTHOR

       Mark Glines, <mark@glines.org>.

COPYRIGHT AND LICENSE

       This code is donated to the frozen bubble project, www.frozen-bubble.org, so they can do whatever they want with it.  Copyright is
       therefore assigned to those guys.

perl v5.14.2							    2012-06-21				     Games::FrozenBubble::NetDiscover(3pm)