YAPC::Asia 2009 2009/09/10
dann
techmemo@gmail.com
Angelos github.com/dann dann

• Dann
• Creator of Angelos
• Yet Another WAF
• http://github.com/dann/
Angelos github.com/dann dann

Angelos github.com/dann dann

Usability
Extendability
Testability
Angelos github.com/dann dann

Angelos github.com/dann dann

recieve a request and return a
Engine response
(Server Abstraction)
Component
Dispatcher Manager
URL to Controller
resolver Load and search component
Angelos github.com/dann dann

Angelos github.com/dann dann

sub build_engine {
my $self = shift;
my $request_handler = $self->request_handler;
$request_handler ||= $self->build_request_handler;
return Angelos::PSGI::Engine->new(
interface => {
module => $self->server, the type of server
.... gateway
},
psgi_handler => $request_handler,
);
} psgi handler which is passed to
the server gateay
Angelos github.com/dann dann

use Mouse;
use Angelos::Types qw( ServerGateway );
has 'interface' => (
is => 'ro', Create Server Gateway
isa => ServerGateway,
coerce => 1,
);
pass psgi handler to server
has 'psgi_handler' => ( is => 'rw', ); gateway
sub run {
my $self = shift;
$self->interface->run( $self->psgi_handler );
}
Angelos github.com/dann dann

package Angelos::PSGI::ServerGatewayBuilder;
use strict;
use warnings;
use Plack::Loader;
Create server gateway with
Plack::Loader
sub build {
my ( $class, $module, $args ) = @_;
my $server_gateway = Plack::Loader->load( $module,
%{$args} );
$server_gateway;
}
Angelos github.com/dann dann

recieve PSGI env
... and convert it to WAF Request
sub {
my $env = shift;
my $req = Angelos::Request->new($env);
my $res = $self->handle_request($req);
my $psgi_res = $self->finalize_response($res);
return $psgi_res;
}
... return PSGI response
Angelos github.com/dann dann

recive a request
sub handle_request { dispatch request to
my ( $self, $req ) = @_;
Dispatcher
eval { $self->DISPATCH($req); };
if ( my $e = Exception::Class->caught() ) {
$self->HANDLE_EXCEPTION($e);
}
# return response
return $self->context->res;
}
Angelos github.com/dann dann

Dispatch a request do
sub DISPATCH { dispatcher
my ( $self, $req ) = @_;
my $dispatch = $self->dispatcher->dispatch($req);
...
$dispatch->run;
# return response
$c->res;
}
Angelos github.com/dann dann

sub dispatch { <URL to Controller>
my ( $self, $request ) = @_; search controller name
based on the request path
with HTTP::Router
my $match = $self->router->match($request);
my $dispatch = $self->dispatch_class->new( match =>
$match );
return $dispatch; Create dispatch
}
instance
Angelos github.com/dann dann

my $controller = $match->params->{controller};
my $controller_instance = $self-
>find_controller_instance( search a controller
{ context => $c, instance from Component
controller => $controller, Manager
}
);
... execute Controller’s
action and return response.
$controller_instance->_dispatch_action( $action,
$params );
Angelos github.com/dann dann

conf/routes.pl- define routing information
HTTP::Router->define(
sub {
$_->match('/')->to( { controller => 'Root', action
=> 'index' } );
$_->resources('Book');
}
);
Angelos github.com/dann dann

.----------------------------------------------+------------+------------+--------------.
| path | method | controller | action |
+---------------------------------------------+------------+------------+------------+
|/ | | Root | index |
| /book.{format} | POST | Books | create |
| /book | POST | Books | create |
| /book.{format} | GET | Books | index |
| /book | GET | Books | index |
| /book/new.{format} | GET | Books | post |
| /book/new | GET | Books | post |
| /book/{book_id}.{format} | GET | Books | show |
| /book.{format} | POST | Books | create |
| /book | POST | Books | create |
| /book.{format} | GET | Books | index |
| /book.{bookk_id}.{format} | DELETE | Books | destroy |
| /book/{book_id} | DELETE | Books | destroy |
| /book/{book_id}.{format} | PUT | Books | update |
| /book/{book_id} | PUT | Books | update |
'-----------------------------------------------+------------+------------+-------------
Angelos github.com/dann dann

• It’s really easy to develop basic
elements of WAF
• You can develop simple WAF
like Sinatra in 4 or 5 hours
Angelos github.com/dann dann

Angelos github.com/dann dann

• What the plugin architecture of WAF
SHOULD be
• The type of Plugins
• How to develop plugin architecture of
WAF
• Example: the plugin of Angelos
Angelos github.com/dann dann

What the plugin architecture of WAF SHOULD
• the core elements of WAF should be as
small as possible and the all parts of WAF
should be extendable and pluggable
• The scope of plugin should be limeted
• Controller,View, Middleware, Request,
Response
• Extension point must be declaretive
Angelos github.com/dann dann

• Hook WAF’s Lifecycle
• Add methods to WAF’s class
Angelos github.com/dann dann

• Hook WAF’s lifecycle
• Mouse’s Role + method modifier
• Class::Trigger
• MouseX::Object::Pluggable
• Add methods to WAF’s classes
• Mouse’s Role
• Exporter
• Multiple inheritance
Angelos github.com/dann dann

• Make Plugin as Role
• User consume plugins in the WAF Component
• Hook WAF’s lifecycle with method modifier
• hook Component’s hook point
• Declare hook point method with CAPITAL
character
Angelos github.com/dann dann

sub _dispatch_action {
my ( $self, $action, $params ) = @_;Declare hook point with
... Capital character
eval { $self->ACTION( $self->context, $action, $params ); };
...
}
Angelos github.com/dann dann

before 'ACTION' => sub {
my ( $self, $c, $action, $params ) = @_;
$self->__action_start_time( time() );
};
after 'ACTION' => sub {
my ( $self, $c, $action, $params ) = @_;
$self->__action_end_time( time() );
my $elapsed = $self->__action_end_time - $self-
>__action_start_time;
my $message
= "action processing time:naction: $action ntime : $elapsed
secsn";
$self->log->info($message);
};
Angelos github.com/dann dann

• WAF developer should make default plugin sets
which user should use
• if there aren’t default plugins sets...
• How can I use Unicode in WAF?
• ... UseXXX,YYY...
• How can I inflate datetime? ...
Angelos github.com/dann dann

• The basic elements of WAF
• Engine, Dispatcher, Component Loader
• WAF’s plugin
• Hook WAF Lifecycle or add a Method to the
Component of WAF
• Plugin Scope must be limited
• the plugin and plugins default sets should be
provided by WAF developer
Angelos github.com/dann dann

• It’s really easy to implement WAF now
• Let’s develop modern WAF with us ;)
• Repository
• http://github.com/dann/angelos/tree/master
Angelos github.com/dann dann