Net::Server::Framework::Client - a client library with auto discovery for

Net-Server-Framework documentation Contained in the Net-Server-Framework distribution.

Index

Code Index:

NAME

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Net::Server::Framework::Client - a client library with auto discovery for daemons

VERSION

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This documentation refers to Net::Server::Framework::Client version 1.0.

SYNOPSIS

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A typical invocation looks like this:

    my $data = Net::Server::Framework::Client::talk('DAEMON_TO_TALK_TO',$c);

DESCRIPTION

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This is a lib that is used to interface with daemons. The interface uses by default a Data::Serializer compressed string to exchange information and finds the appropriate daemon based on the name. The name is looked up in the central registry configured with the $DB variable. The database based registry holds connection data like UNIX sockets or TCP sockets. If there is more than one daemon with the same name the lib does a basic round robin.

BASIC METHODS

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c_connect

The connection logic.

encode

The analog to the Net::Server::Framework::encode function only client sides.

decode

The analog to the Net::Server::Framework::decode function only client sides.

talk

This method abstracts the connection logic and the syn/async connection handling. Use this function to talk to a daemon within the Net::Server::Framework.

log

Deprecated. Has to be consolidated to one general function that is backend neutral

logging

See log

CONFIGURATION AND ENVIRONMENT

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The library needs a working etc/db.conf file and a configured $DB variable. If asynchronous connections are used then a spooler process is needed.

BUGS AND LIMITATIONS

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There are no known bugs in this module. Please report problems to Lenz Gschwendtner ( <lenz@springtimesoft.com> ) Patches are welcome.

AUTHOR

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Lenz Gschwendtner ( <lenz@springtimesoft.com> )

LICENCE AND COPYRIGHT

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Copyright (c) 2007 Lenz Gschwerndtner ( <lenz@springtimesoft.comn> ) All rights reserved.

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

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.

Net-Server-Framework documentation Contained in the Net-Server-Framework distribution. 
#!/usr/bin/perl -w -Ilib
#
# a General client library using the Net::Server::Framework framework
#

package Net::Server::Framework::Client;

use strict;
use warnings;
use Carp;
use IO::Socket;
use Net::Server::Framework::DB;
use Net::Server::Framework::Spooler;
use Time::HiRes;
use Data::Serializer;

our ($VERSION) = '1.0';
our $DB = 'registry';

sub c_connect {
    my $service = shift;

    my @hosts = _find($service);
    foreach my $host (@hosts) {
        if ( $host->{host} eq 'unix' ) {
            return IO::Socket::UNIX->new( Peer => $host->{port}, )
              or next;
        }
        else {
            return IO::Socket::INET->new(
                Proto    => "tcp",
                PeerAddr => $host->{host},
                PeerPort => $host->{port},
            ) or next;
        }
    }
    carp("Could not find a valid connection method!");
}

sub encode {
    my $data = shift;
    my $s = Data::Serializer->new( compress => '1' );
    return $s->serialize($data);
}

sub decode {
    my $data = shift;
    my $s = Data::Serializer->new( compress => '1' );
    return $s->deserialize($data);
}

sub talk {
    my ( $mech, $data ) = @_;

    my $start = time();
    my $timeout = 15;
    my $remote = c_connect($mech)
      or carp( "cannot connect to $mech Daemon, check the config section in your program");

    # send the hash to the daemon
    print $remote encode($data);
    shutdown $remote, 1;
    my $resp = <$remote>;
    # we work in asyc mode and have to poll the queue
    if ($resp eq 'accepted')
    {
        while (1) {
            my $res = Net::Server::Framework::Spooler::virgin($data);
            return $res if defined $res;
            if ( time > $start + $timeout ) {
                return 1001;
            }
            Time::HiRes::usleep 100_000;
        }
    } else {
        return decode($resp);
    }
}

#TODO make logging in couchDB
sub logging {
    my $h = shift;
    return $h;
}

sub log {
    my $h = shift;
    $h->{command} = 'put';
    my $id = talk('logD', $h);
    return $h;
}

sub _find {
    my $service = shift;
    my $dbh     = Net::Server::Framework::DB::dbconnect($DB);
    my @ret;
    my $res =
      Net::Server::Framework::DB::get( { dbh => $dbh, key => 'host', term => $service } );
    foreach my $l ( keys %{$res} ) {
        my $ret;
        if ( $l eq '*' ) {
            if ( $res->{$l}->{port} =~ m{\d+} ) {
                $ret->{host} = 'localhost';
                $ret->{port} = $res->{$l}->{port};
            }
            else {
                $ret->{host} = 'unix';
                $ret->{port} = $res->{$l}->{port};
            }
        }
        else {
            $ret->{host} = $l;
            $ret->{port} = $res->{$l}->{port};
        }
        push( @ret, $ret );
    }
    return @ret;
}

1;