POE
Stefano Rodighiero
OpenExp 2006

Perl
Object
Environment
POE - A Perl Object Environment

?
POE - A Perl Object Environment

Framework
POE - A Perl Object Environment

Event
driven
POE - A Perl Object Environment

Multitasking
Cooperativo
POE - A Perl Object Environment

Single
thread
POE - A Perl Object Environment

Networking
POE - A Perl Object Environment

System
administration
POE - A Perl Object Environment

GUI
POE - A Perl Object Environment

POE - A Perl Object Environment

Component
Wheel
“Architettura”
Session
Kernel
POE - A Perl Object Environment

Component
Wheel
Dispatch di eventi
Session
Kernel
POE - A Perl Object Environment

Component
Wheel
Risponde agli eventi
Session
Kernel
POE - A Perl Object Environment

Component
“Plugin” per sessioni,
incapsula insiemi di
Wheel
gestori di eventi
Session POE::Wheel::FollowTail
POE::Wheel::Run
Kernel
POE - A Perl Object Environment

Component
Wheel POE::Component::IRC
POE::Component::Server::TCP
POE::Component::Server::SimpleHTTP
…CPAN…
Session
Kernel
POE - A Perl Object Environment

POE - A Perl Object Environment

Un programma tipico
• Istanzia una o più sessioni
• Esplicitamente, eventualmente usando
delle Wheel
• Implicitamente, con Componenti già
pronti
• POE::Kernel->run()
POE - A Perl Object Environment

sub POE::Kernel::TRACE_EVENTS() { 1 }
POE - A Perl Object Environment

use POE;
POE - A Perl Object Environment

for ( 1 .. 3 ) {
POE::Session -> create(
inline_states => {
_start => sub { print quot;Start!nquot; },
_stop => sub { print quot;Stop!nquot; }
} );
}
POE - A Perl Object Environment

POE::Kernel->run();
POE - A Perl Object Environment

_start
Session
Kernel
POE - A Perl Object Environment

_start
Session
_start =>
sub {
print quot;Start!nquot;
Kernel
}
POE - A Perl Object Environment

Passaggio di messaggi
Accoda un evento, da inoltrare
post() alla session specificata
Accoda un evento, da inoltrare
yield() alla session stessa
Invoca - in maniera
sincrona - un evento per una
call()
sessione specificata
POE - A Perl Object Environment

Passaggio di messaggi
post()/yield()
POE - A Perl Object Environment

Passaggio di messaggi
call()
POE - A Perl Object Environment

Comunicazione
tra sessioni
POE - A Perl Object Environment

# Sessione Babbo Natale
POE::Session->create(
inline_states => {
_start => sub {
print quot;Oh oh oh!nquot;;
$poe_kernel->alias_set( quot;Santaquot; );
},
lettera => sub {
print quot;Lettera da quot;
. $poe_kernel->alias_list( $_[SENDER] );
}
}
);
POE - A Perl Object Environment

# Sessione Babbo Natale
POE::Session->create(
inline_states => {
_start => sub {
print quot;Oh oh oh!nquot;;
$poe_kernel->alias_set( quot;Santaquot; );
},
lettera => sub {
print quot;Lettera da quot;
. $poe_kernel->alias_list( $_[SENDER] );
}
}
);
POE - A Perl Object Environment

# Sessione Babbo Natale
POE::Session->create(
inline_states => {
_start => sub {
print quot;Oh oh oh!nquot;;
$poe_kernel->alias_set( quot;Santaquot; );
},
lettera => sub {
print quot;Lettera da quot;
. $poe_kernel->alias_list( $_[SENDER] );
}
}
);
POE - A Perl Object Environment

# Sessione Babbo Natale
POE::Session->create(
inline_states => {
_start => sub {
print quot;Oh oh oh!nquot;;
$poe_kernel->alias_set( quot;Santaquot; );
},
lettera => sub {
print quot;Lettera da quot;
. $poe_kernel->alias_list( $_[SENDER] );
}
}
);
POE - A Perl Object Environment

# Sessione bimbo
POE::Session->create(
inline_states => {
_start => sub {
$poe_kernel->alias_set( quot;Paolinoquot; );
$poe_kernel->post( quot;Santaquot; => 'lettera' );
},
}
);
POE - A Perl Object Environment

# Sessione bimbo
POE::Session->create(
inline_states => {
_start => sub {
$poe_kernel->alias_set( quot;Paolinoquot; );
$poe_kernel->post( quot;Santaquot; => 'lettera' );
},
}
);
POE - A Perl Object Environment

Babbo Natale _start
Kernel
Paolino
_start
POE - A Perl Object Environment

Babbo Natale
Kernel
Paolino
post( quot;Santaquot;, quot;letteraquot; )
POE - A Perl Object Environment

lettera
Babbo Natale
Kernel
Paolino
POE - A Perl Object Environment

lettera
Babbo Natale
lettera
Kernel
Paolino
post( quot;Santaquot;, quot;letteraquot; )
POE - A Perl Object Environment

POE - A Perl Object Environment

Wheel
POE - A Perl Object Environment

Insiemi di
gestori di
eventi
POE - A Perl Object Environment

POE::
Wheel::
FollowTail
POE - A Perl Object Environment

use POE qw(