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Kossy-0.62
River stage one • 1 direct dependent • 1 total dependent
/ Kossy

NAME

Kossy - Sinatra-ish Simple and Clear web application framework

SYNOPSIS

% kossy-setup MyApp
% cd MyApp
% plackup app.psgi

## lib/MyApp/Web.pm

use Kossy;

get '/' => sub {
    my ( $self, $c )  = @_;
    $c->render('index.tx', { greeting => "Hello!" });
};

get '/json' => sub {
    my ( $self, $c )  = @_;
    my $result = $c->req->validator([
        'q' => {
            default => 'Hello',
            rule => [
                [['CHOICE',qw/Hello Bye/],'Hello or Bye']
            ],
        }
    ]);
    $c->render_json({ greeting => $result->valid->get('q') });
};

1;

## views/index.tx
: cascade base
: around content -> {
  <: $greeting :>
: }

DESCRIPTION

Kossy is Sinatra-ish Simple and Clear web application framework, which is based upon Plack, Router::Boom, Text::Xslate and build-in Form-Validator. That's suitable for small application and rapid development.

Kossy class

Kossy exports some methods to building application

CLASS METHODS for Kossy class

my $kossy = Kossy->new( root_dir => $root_dir );

Create instance of the application object.

OBJECT METHODS for Kossy class

my $root_dir = $kossy->root_dir();

accessor to root directory of the application

my $app = $kossy->psgi();

return PSGI application

DISPATCHER METHODS for Kossy class

filter

makes application wrapper like plack::middlewares.

filter 'set_title' => sub {
    my $app:CODE = shift;
    sub {
        my ( $self:Kossy, $c:Kossy::Connection )  = @_;
        $c->stash->{site_name} = __PACKAGE__;
        $app->($self,$c);
    }
};
get path:String => [[filters] =>] CODE
post path:String => [[filters] =>] CODE

setup router and dispatch code

get '/' => [qw/set_title/] => sub {
    my ( $self:Kossy, $c:Kossy::Connection )  = @_;
    $c->render('index.tx', { greeting => "Hello!" });
};

get '/json' => sub {
    my ( $self:Kossy, $c:Kossy::Connection )  = @_;
    $c->render_json({ greeting => "Hello!" });
};

dispatch code shall return Kossy::Response object or PSGI response ArrayRef or String.

router 'HTTP_METHOD'|['METHOD'[,'METHOD']] => path:String => [[filters] =>] CODE

adds routing rule other than GET and POST

router 'PUT' => '/put' => sub {
    my ( $self:Kossy, $c:Kossy::Connection )  = @_;
    $c->render_json({ greeting => "Hello!" });
};

Kossy::Connection class

per-request object, herds request and response

OBJECT METHODS for Kossy::Connection class

req:Kossy::Request
res:Kossy::Response
stash:HashRef
args:HashRef

Router::Simple->match result

halt(status_code, message)

die and response immediately

redirect($uri,status_code): Kossy::Response
render($file,$args): Kossy::Response

calls Text::Xslate->render makes response. template files are searching in root_dir/views directory

template syntax is Text::Xslate::Syntax::Kolon, can use Kossy::Connection object and fillinform block.

## template.tx
: block form |  fillinform( $c.req ) -> {
<head>
<title><: $c.stash.title :></title>
</head>
<body>
<form action="<: $c.req.uri_for('/post') :>">
<input type="text" size="10" name="title" />
<textarea name="body" rows="20" cols="90"></textarea>
</form>
</body>
: }

also can use Text::Xslate::Bridge::TT2Like and Number::Format methods in your template

render_json($args): Kossy::Response

serializes arguments with JSON and makes response

This method escapes '<', '>', and '+' characters by "\uXXXX" form. Browser don't detects the JSON as HTML. And also this module outputs "X-Content-Type-Options: nosniff" header for IEs.

render_json have a JSON hijacking detection feature same as Amon2::Plugin::Web::JSON. This returns "403 Forbidden" response if following pattern request.

The request have 'Cookie' header.
The request doesn't have 'X-Requested-With' header.
The request contains /android/i string in 'User-Agent' header.
Request method is 'GET'

Kossy::Request

This class is child class of Plack::Request, decode query/body parameters automatically. Return value of $req->param(), $req->body_parameters, etc. is the decoded value.

OBJECT METHODS for Kossy::Request class

uri_for($path,$args):String

build absolute URI with path and $args

my $uri = $c->req->uri_for('/login',[ arg => 'Hello']);
validator($rule):Kossy::Validator::Result

validate parameters using Kossy::Validator

my $result = $c->req->validator([
  'q' => [['NOT_NULL','query must be defined']],
  'level' => {
      default => 'M',
      rule => [
          [['CHOICE',qw/L M Q H/],'invalid level char'],
      ],
  },
]);

my $val = $result->valid('q');
my $val = $result->valid('level');
body_parameters_raw
query_parameters_raw
parameters_raw
param_raw

These methods are the accessor to raw values. 'raw' means the value is not decoded.

body_parameters

Accessor to decoded body parameters. It's Hash::MultiValue object.

query_parameters

Accessor to decoded query parameters. It's Hash::MultiValue object.

json_parameters

Accessor to decoded JSON body parameters. It's NOT Hash::MultiValue object.

post '/api' => sub {
    my ($self, $c) = @_;
    my $foo = $c->req->json_parameters->{foo}; # bar
};

# requrest
# $ua->requrest(
#     HTTP::Request->new(
#         "POST",
#         "http://example.com/api",
#         [ "Content-Type" => 'application/json', "Content-Length" => 13 ],
#         '{"foo":"bar"}'
#     )
# );

NOTE: Not need to set kossy.request.parse_json_body to 1

Kossy::Response

This class is child class of Plack::Response

CUSTOMIZE

X-Frame-Options

By default, Kossy outputs "X-Frame-Options: DENY". You can change this header

get '/iframe' => sub {
    my ($self, $c) = @_;
    $c->res->header('X-Frame-Options','SAMEORIGIN');
    # or remove from response header
    # delete $c->res->headers->remove_header('X-Frame-Options');
    ..
}

(Default: DENY)

kossy.request.parse_json_body

If enabled, Kossy will decode json in the request body that has "application/json" content header

post '/api' => sub {
    my ($self, $c) = @_;
    $c->env->{'kossy.request.parse_json_body'} = 1;
    my val = $c->req->param('foo'); # bar
}

# requrest
# $ua->requrest(
#     HTTP::Request->new(
#         "POST",
#         "http://example.com/api",
#         [ "Content-Type" => 'application/json', "Content-Length" => 13 ],
#         '{"foo":"bar"}'
#     )
# );
$XSLATE_CACHE, $XSLATE_CACHE_DIR

Change xslate's cache level and cache directory.

local $Kossy::XSLATE_CACHE = 2;
local $Kossy::XSLATE_CACHE_DIR = $dir;
my $app = MyApp::Web->psgi;

By default, $XSLATE_CACHE is 1, $XSLATE_CACHE_DIR is undef. use Xslate's default.

$SECURITY_HEADER

If disabled, Kossy does not set X-Frame-Options and X-XSS-Protection. enabled by default.

local $Kossy::SECURITY_HEADER = 0;
my $app = MyApp::Web->psgi;

Can not change $Kossy::SECURITY_HEADER in your WebApp. It's need to set at build time.

This is useful for the benchmark :-)

$JSON_SERIALIZER

changes the JSON serializer:

use Cpanel::JSON::XS;
use Cpanel::JSON::XS::Type;

local $Kossy::JSON_SERIALIZER = Cpanel::JSON::XS->new()->allow_blessed(1)->convert_blessed(1)->ascii(0);

get '/' => sub {
    my ($self, $c) = @_;
    return $c->render_json({ a => '234' }, { a => JSON_TYPE_INT });
};

my $app = __PACKAGE__->psgi;

AUTHOR

Masahiro Nagano <kazeburo {at} gmail.com>

SEE ALSO

Kossy is small waf, that has only 400 lines code. so easy to reading framework code and customize it. Sinatra-ish router, build-in templating, validators and zero-configuration features are suitable for small application and rapid development.

Amon2::Lite

Mojolicious::Lite

Dancer

Kossy::Validator

LICENSE of HTTP::Headers::Fast

Kossy::Headers uses HTTP::Headers::Fast code. Here is LICENSE of HTTP::Headers::Fast

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

LICENSE

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