Run a website with Perl? - you should learn how to use Plack. Most Perl web frameworks support it and it makes your life a lot easier and a lot more fun

1. Plack Basics
Leo Lapworth @ YAPC::EU 2011
Much content from Tatsuhiko Miyagawa’s
YAPC::NA 2010 talk

2. What is Plack?

3. What is Plack?
“Superglue for Perl 5 Web
Frameworks and Web
Servers”

4. How will that help me?

5. How will that help me?
‣ Flexibility

6. How will that help me?
‣ Flexibility
‣ Middleware (plugins)

7. How will that help me?
‣ Flexibility
‣ Middleware (plugins)
‣ Apps

8. How will that help me?
‣ Flexibility
‣ Middleware (plugins)
‣ Apps
‣ Development

9. How will that help me?
‣ Flexibility
‣ Middleware (plugins)
‣ Apps
‣ Development
‣ Testing

10. How will that help me?
‣ Flexibility
‣ Middleware (plugins)
‣ Apps
‣ Development
‣ Testing
‣ Deployment

11. How will that help me?
‣ Flexibility
‣ Middleware (plugins)
‣ Apps
‣ Development
‣ Testing
‣ Deployment
‣ World peace

12. How will that help me?
‣ Flexibility
‣ Middleware (plugins)
‣ Apps
‣ Development
‣ Testing
‣ Deployment
‣ World peace

13. History...

14. Hello World

15. #!/usr/bin/perl
use strict;
print “Content-Type: text/plainrnrn”;
print “Hello World”;

16. package HelloWorld;
use strict;
use Apache::RequestRec;
use Apache::RequestIO;
use Apache::Const -compile => qw(OK);
sub handler {
my $r = shift;
$r->content_type(‘text/plain’);
$r->print(“Hello World”);
return Apache::Const::OK;
}
1;

17. use FCGI;
my $req = FCGI::Request();
while ($req->Accept >= 0) {
print “Content-Type: text/plainrnrn”;
print “Hello World”;
}

18. package HelloWorld;
use base qw(HTTP::Server::Simple::CGI);
sub handle_request {
my($self, $cgi) = @_;
print “HTTP/1.0 200 OKrn”;
print “Content-Type: text/plainrnrn”;
print “Hello World”;
}
1;

19. All similar
but slightly different

20. Painful to support
all of them 

21. There was
one common way
to do all of this.

22. CGI.pm

23. #!/usr/bin/perl
use CGI;
my $q = CGI->new;
print $q->header(‘text/plain’);
print “Hello World”;

24. Works under...
CGI
FastCGI
mod_perl
HTTP::Server::Simple::CGI

25. CGI.pm
mod_perl CGI fastcgi
Apache IIS lighttpd

26. CGI.pm?

27. CGI.pm?
meh

28. Frameworks
to the rescue!

30. Catalyst Maypole Mason Mojo Sledge Spoon
PageKit AxKit Egg Gantry Continuity Solstice
Mojolicious Tripletail Konstrukt Reaction Jifty
Cyclone3 WebGUI OpenInteract Squatting
Dancer CGI::Application Nanoa Ark Angelos
Noe Schenker Tatsumaki Amon
Apache2::WebApp Web::Simple Apache2::REST
SweetPea Hydrant Titanium

31. Let’s look how they
handled web servers.

32. CGI.pm
mod_perl CGI fastcgi
Apache IIS lighttpd

33. CGI::Application
Apache IIS lighttpd

34. CGI::Application
CGI.pm
Apache IIS lighttpd

35. CGI::Application
CGI.pm
mod_perl CGI fastcgi
Apache IIS lighttpd

36. CGI::Application Jifty
CGI.pm
mod_perl CGI fastcgi
Apache IIS lighttpd

37. CGI::Application Jifty Catalyst
CGI.pm
mod_perl CGI fastcgi
Apache IIS lighttpd

38. CGI::Application Jifty Catalyst
CGI.pm Catalyst::Engine
mod_perl CGI fastcgi
Apache IIS lighttpd

39. CGI::Application Jifty Catalyst
CGI.pm Catalyst::Engine
mod_perl CGI fastcgi
Apache IIS lighttpd nginx

40. CGI::Application Jifty Catalyst
CGI.pm Catalyst::Engine
mod_perl CGI fastcgi
HTTP::Server
::Simple Apache IIS lighttpd nginx

41. Mason CGI::Application Jifty Catalyst
CGI.pm Catalyst::Engine
mod_perl CGI fastcgi
HTTP::Server
::Simple Apache IIS lighttpd nginx

42. Mason CGI::Application Jifty Catalyst
Mason::CGIHandler
CGI.pm Catalyst::Engine
mod_perl CGI fastcgi
HTTP::Server
::Simple Apache IIS lighttpd nginx

43. Gross.

44. CGI.pm
Jifty, CGI::Application, Spoon
mod_perl centric
Mason, Sledge, PageKit, WebGUI
Adapters
Catalyst, Maypole, Squatting

45. That was 2008...

46. Gentleman thief &
Double agent
Miyagawa

47. Acquired a great idea
from Python/Ruby

48. WSGI (Python)
Rack (Ruby)

49. WSGI (PEP-333)

50. WSGI Python Frameworks
• Django • mod_wsgi
• Bottle • Paste
• CherryPy • gunicorn
• Tornado • uWSGI
• Pylons • wsgiref
• Flask • Google AppEngine

51. Django Bottle Flask Tornado
WSGI middleware
WSGI
wsgi handlers
Apache lighttpd nginx mod_wsgi GAE

52. Rack

53. Rack Ruby Frameworks
• Rails • Unicorn
• Merb • Thin
• Sinatra • Mongrel
• Camping • Rainbows!
• Ramaze • Phusion Passenger
• etc. • Heroku

54. Rails Merb Sinatra Ramaze
Rack middleware
Rack
Rack handlers
Apache lighttpd Thin Unicorn Mongrel

55. Perl ?

56. PSGI Perl ?
Perl Web Server Gateway Interface

57. Interface

58. Interface

59. Interface
PSGI != Plack

60. PSGI application
code reference
$app = sub {...};

61. # PSGI Hello World
my $app = sub {
my $env = shift;
return [
200,
[ ‘Content-Type’, ‘text/plain’ ],
[ ‘Hello World’ ],
];
};

62. my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
CGI-like environment variables
+ psgi.input, psgi.errors etc.

63. my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
HTTP status code (int.): 200, 404 etc.

64. my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
Array reference of header pairs:
[ ‘Content-Type’, ‘text/html’, ... ]

65. my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
String, array reference of content chunks,
Filehandle or IO::Handle-ish object

66. That’s it.
(There’s a callback based streaming interface as well)

67. # PSGI
my $app = sub {
my $env = shift;
return [
200,
[ ‘Content-Type’, ‘text/plain’ ],
[ ‘Hello World’ ],
];
};

68. Now you’ve got
a PSGI compatible
application.

69. Mason CGI::App Jifty Catalyst
Mason::CGIHandler
CGI.pm Catalyst::Engine
mod_perl CGI fastcgi
HTTP::Server
::Simple Apache IIS lighttpd nginx

70. Catalyst CGI::App Jifty Mason 2
Plack::Middleware
PSGI Compatible App
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal

71. Catalyst CGI::App Jifty Mason 2
Plack::Middleware
PSGI Compatible App
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
other PSGI Webservers

72. Web Servers

73. Plack::Handler
Connects PSGI compatible apps
to Web servers...

74. FCGI
Plack::Handler::FCGI

75. Apache
Plack::Handler::Apache1
Plack::Handler::Apache2

76. Starman
UNIX Preforking HTTP servers (like Unicorn.rb)
HTTP/1.1 chunk + keep-alives / Very Fast

77. HTTP::Server::Simple::PSGI
Zero-deps other than HTTP::Server::Simple
Best for embedding PSGI applications

78. Twiggy
Non-blocking web server (like Thin.rb)
based on AnyEvent framework
Starlet
Simpler UNIX HTTP/1.0 Server
Best used with Server::Starter and nginx/lighttpd

79. Perlbal plugin
http://github.com/miyagawa/Perlbal-Plugin-PSGI

80. nginx embedded perl
http://github.com/yappo/nginx-psgi-patchs

81. mod_psgi
http://github.com/spiritloose/mod_psgi
Apache2

82. Corona uWSGI
Coroutine for each connection http://projects.unbit.it/uwsgi/
based on Coro.pm
Feersum evpsgi
http://github.com/stash/Feersum http://github.com/sekimura/evpsgi
Gepok
http://metacpan/module/Gepok
Pure Perl standalone HTTPS
First released July 2011

83. Frameworks Apps Your own code
Plack::Middleware
PSGI
Plack::Handler::* (CGI, FCGI, Apache)

84. Frameworks Apps Your own code
Plack::Middleware
PSGI
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona etc, etc

85. 25+ Plack::Handlers

86. Adoption?

87. Plack::Middleware
PSGI Compatible App
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona etc

88. ?
Plack::Middleware
PSGI Compatible App
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona etc

89. Catalyst Maypole Mason Mojo Sledge Spoon PageKit
AxKit Egg Gantry Continuity Solstice Mojolicious
Tripletail Konstrukt Reaction Jifty Cyclone3 WebGUI
OpenInteract Squatting Dancer CGI::Application
Nanoa Ark Angelos Noe Schenker Tatsumaki Amon
Apache2::WebApp Web::Simple Apache2::REST
SweetPea Hydrant Titanium

90. Catalyst Maypole Mason Mojo Sledge Spoon PageKit
AxKit Egg Gantry Continuity Solstice Mojolicious
Tripletail Konstrukt Reaction Jifty Cyclone3 WebGUI
OpenInteract Squatting Dancer CGI::Application
Nanoa Ark Angelos Noe Schenker Tatsumaki Amon
Apache2::WebApp Web::Simple Apache2::REST
SweetPea Hydrant Titanium

91. PSGI Perl Frameworks
• Amon • Hydrant • Schenker
• Angelos • Jifty • Sledge
• Ark • Mason • Squatting
• Catalyst • Maypole • Tatsumaki
• CGI::Application • Mojo • Titanium
• Continuity • Mojolicious • Web::Simple
• Dancer • Noe

92. Applications
Movable Type 6
WebGUI 8
RT4
ACT (conference toolkit)
Bricolage (if someone gets time)

93. Plack::Middleware
PSGI Compatible App
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona evpsgi

94. Catalyst CGI::App Jifty Tatsumaki
Dancer Mojoliscious MT6 Mason 2
Web::Simple WebGui 8 Mojo etc...
Plack::Middleware
PSGI Compatible App
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona evpsgi

95. PSGI from a framework

96. use Dancer;
get ‘/’ => sub {
“Hello World”;
};
dance;

97. use Mojolicious::Lite;
get ‘/:name’ => sub {
my $self = shift;
$self->render_text(‘Hello!’);
};
app->start;

98. use My::Jifty::App;
my $app = My::Jifty::App->psgi_app;

99. use Web::Simple ‘MyApp’;
package MyApp;
dispatch {
sub(GET) {
[ 200, [...], [ ‘Hello’ ] ];
}
};
my $app = MyApp->as_psgi;

100. use My::Catalyst::App;
My::Catalyst::App->setup_engine(‘PSGI’);
my $app = sub {
My::Catalyst::App->run(@_)
};

104. catalyst.pl My::Catalyst::App

105. Plack
“PSGI implementation & toolkit”

106. Plack toolkit

107. Plack toolkit
Plack::Handlers Connect PSGI apps and Web Servers

108. Plack toolkit
Plack::Handlers Connect PSGI apps and Web Servers
plackup Command line launcher

109. Plack toolkit
Plack::Handlers Connect PSGI apps and Web Servers
plackup Command line launcher
Plack::Loader (auto)load Plack Servers

110. Plack toolkit
Plack::Handlers Connect PSGI apps and Web Servers
plackup Command line launcher
Plack::Loader (auto)load Plack Servers
Plack::Middleware Easy-to-use PSGI Middleware

111. Plack toolkit
Plack::Handlers Connect PSGI apps and Web Servers
plackup Command line launcher
Plack::Loader (auto)load Plack Servers
Plack::Middleware Easy-to-use PSGI Middleware
Plack::Builder OO & DSL to enable Middleware

112. Plack toolkit
Plack::Handlers Connect PSGI apps and Web Servers
plackup Command line launcher
Plack::Loader (auto)load Plack Servers
Plack::Middleware Easy-to-use PSGI Middleware
Plack::Builder OO & DSL to enable Middleware
Plack::Apps Apps

113. Plack toolkit
Plack::Handlers Connect PSGI apps and Web Servers
plackup Command line launcher
Plack::Loader (auto)load Plack Servers
Plack::Middleware Easy-to-use PSGI Middleware
Plack::Builder OO & DSL to enable Middleware
Plack::Apps Apps
Plack::Test Testing

114. plackup
Runs PSGI app instantly from CLI
(inspired by rackup)

115. > plackup app.psgi

116. > plackup app.psgi
HTTP::Server::PSGI: Accepting
connections at http://0:5000/

117. HTTP::Server::PSGI
Reference PSGI web server
bundled in Plack
Standalone, single-process HTTP server
great for development and testing

118. Plack::Middleware
(160+ modules - July 2011)

119. Middleware
Debug, Session, Logger, Static, Lint,
AccessLog, ErrorDocument, StackTrace, Auth::Basic,
Auth::Digest, ReverseProxy, Refresh, Auth::OAuth,
Throttle....

121. Chunked Class::Refresh Compile Conditional ConditionalGET
ConsoleLogger ContentLength ContentMD5 CrossOrigin
CSRFBlock Dancer::Debug DBIC::QueryLog Debug
Debug::CatalystPluginCache Debug::DBIC::QueryLog
Debug::DBIProfile Debug::Profiler::NYTProf Debug::W3CValidate
Deflater DoCoMoGUID Doorman ErrorDocument ESI ETag
Expires File::Sass Firebug::Lite FirePHP ForceEnv Head Header
HTMLify HTMLMinify HTTPExceptions IEnosniff IIS6ScriptNameFix
Image::Scale Inline InteractiveDebugger IPAddressFilter iPhone
JavaScript::Ectype JSConcat JSONP LighttpdScriptNameFix Lint
Log::Contextual Log::Minimal Log4perl LogDispatch LogWarn
MethodOverride Mirror NeverExpire NoDeflate NoMultipleSlashes
NullLogger Options OptionsOK Precompressed ProxyMap
RearrangeHeaders Recursive RefererCheck Refresh REPL Reproxy
ReverseProxy Rewrite Runtime Scope::Container Scope::Session
ServerStatus::Lite Session Session::SerializedCookie SetAccept
SimpleContentFilter SimpleLogger SizeLimit SocketIO SSI
StackTrace Static Static::Minifier StaticShared Status
Test::StashWarnings Throttle TMT UseChromeFrame Watermark

122. Plack Middleware
Wraps a PSGI application
to add pre/post processing

124. Logging

125. Logging
Status code redirect

126. Logging
Status code redirect
Error Handler

127. Logging
Status code redirect
Error Handler
Cache Middleware

128. Logging
Status code redirect
Error Handler
Cache Middleware
Session Middleware

129. Logging
Status code redirect
Error Handler
Cache Middleware
Session Middleware
Routes Middleware

130. Logging
Status code redirect
Error Handler
Cache Middleware
Session Middleware
Routes Middleware
Your App

131. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App

132. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in

133. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in
P::MW::A

134. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in
P::MW::A
P::MW::B

135. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in
P::MW::A
P::MW::B
PSGI App

136. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in
P::MW::A
P::MW::B P::MW::B
PSGI App

137. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in
P::MW::A P::MW::A
P::MW::B P::MW::B
PSGI App

138. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in Response out
P::MW::A P::MW::A
P::MW::B P::MW::B
PSGI App

139. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in e.g. Redirect Response out
P::MW::A P::MW::A
P::MW::B P::MW::B
PSGI App

140. Plack::Middleware::A
Plack::Middleware::B
PSGI Compatible App
Request in e.g. Redirect Response out
P::MW::A P::MW::A
e.g. Static
P::MW::B P::MW::B
PSGI App

141. Enabling
Plack::Middleware
reusable and extensible
Middleware framework
Plack::Builder DSL in .psgi

142. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “A”;
enable “B”;
$app;
}

143. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “A”;
enable “B”;
$app;
}

144. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “A”;
enable “B”;
$app;
}

145. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “A”;
enable “B”;
$app;
}

146. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “A”; # Plack::Middleware::A
enable “B”; # Order matters
$app;
}

147. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “A”;
enable “B”;
$app;
}

148. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “Static”, root => “/htdocs”,
path => qr!^/static/!;
enable “Deflater”;
$app;
}

149. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “Static”, root => “/htdocs”,
path => qr!^/static/!;
enable “Deflater”;
$app;
}

150. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “Static”, root => “/htdocs”,
path => qr!^/static/!;
enable “Deflater”; # gzip/deflate
$app;
}

151. my $app = sub {
return [ $status, $header, $body ];
};
use Plack::Builder;
return builder {
enable “Static”, root => “/htdocs”,
path => qr!^/static/!;
enable “Deflater”;
$app;
}

152. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App

153. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in

154. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in
Static

155. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in Response out
=~ ^/static
Static

156. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in Response out
=~ ^/static
Static
-

157. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in Response out
=~ ^/static
Static
-
PSGI App

158. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in Response out
=~ ^/static
Static
- Deflate compresses
PSGI App

159. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in Response out
=~ ^/static
Static -
- Deflate compresses
PSGI App

160. Plack::Middleware::Static
Plack::Middleware::Deflate
PSGI Compatible App
Request in Response out
=~ ^/static
Static -
- Deflate compresses
PSGI App

161. plackup compatible
plackup -e ‘enable “Foo”;’ app.psgi

162. Middleware
Write once, run in every framework

163. A few demos..

164. Assume...
use Plack::Builder;
my $body = ‘<html><body>Hello World</body></html>’;
my $app = sub {
my $self = shift;
return [200, ['Content-Type' => 'text/html'], [ $body ]];
};

165. Assume...
use Plack::Builder;
my $body = ‘<html><body>Hello World</body></html>’;
my $app = sub {
my $self = shift;
return [200, ['Content-Type' => 'text/html'], [ $body ]];
};

166. Assume...
use Plack::Builder;
my $body = ‘<html><body>Hello World</body></html>’;
my $app = sub {
my $self = shift;
return [200, ['Content-Type' => 'text/html'], [ $body ]];
};

167. Debugger

168. return builder {
# Precious debug info. Right on your page!
enable 'Debug';
$app;
}

177. InteractiveDebugger

178. my $app = sub {
my $foo = 'bar';
die "oops" if $foo eq 'bar';
[200, ['Content-Type' => 'text/html'], [ $body ]];
};
return builder {
# Enable Interactive debugging
enable "InteractiveDebugger";
$app;
}

179. my $app = sub {
my $foo = 'bar';
die "oops" if $foo eq 'bar';
[200, ['Content-Type' => 'text/html'], [ $body ]];
};
return builder {
# Enable Interactive debugging
enable "InteractiveDebugger";
$app;
}

180. my $app = sub {
my $foo = 'bar';
die "oops" if $foo eq 'bar';
[200, ['Content-Type' => 'text/html'], [ $body ]];
};
return builder {
# Enable Interactive debugging
enable "InteractiveDebugger";
$app;
}

187. NYTProf - profiler

188. First rule of Program
Optimisation

189. Don’t do it!

190. Second rule of Program
Optimisation
(for experts only)

191. Don’t do it -
yet!

192. return builder {
enable 'Debug', panels => [ [ 'Profiler::NYTProf' ] ];
$app;
};

198. ServerStatus::Lite

199. use Plack::Builder;
return builder {
enable "ServerStatus::Lite",
path => '/server-status',
allow => [ '127.0.0.1'],
scoreboard => '/tmp/score';
$app;
}

204. SizeLimit

205. use Plack::Builder;
return builder {
enable "SizeLimit",
max_unshared_size_in_kb => 3000,
check_every_n_requests => 5;
$app;
}

206. Plack::App::*
ready-to-use applications

208. Apache::ActionWrapper CGIBin Cascade
CocProxy DAV Directory Directory::Xslate
FCGIDispatcher File ImageMagick JSP PSGIBin
Path::Router Proxy
Proxy::Backend::AnyEvent::HTTP
Proxy::Backend::LWP Proxy::Selective Proxy::Test
URLMap WrapApacheReq
WrapApacheReq::FakeRequest WrapCGI

209. Plack::App::CGIBin
mount /cgi-bin as PSGI applications

210. CGI::PSGI
Easy migration from CGI.pm

211. Plack::App::Directory
Static content file server

212. Plack::App::Proxy
(non-blocking) proxy server
Can be used as reverse proxy as well

213. Plack::App::JSP
Runs JavaScript PSGI apps :)

214. # app.psgi - Javascript!
Plack::App::JSP->new( js => q{
function respond(body) {
return [ 200, [ 'Content-type', 'text/html' ], [ body ] ]
}
respond("Five factorial is " +
(function(x) {
if ( x<2 ) return x;
return x * arguments.callee(x - 1);
})(5)
);
});

215. # app.psgi - Javascript!
Plack::App::JSP->new( js => q{
function respond(body) {
return [ 200, [ 'Content-type', 'text/html' ], [ body ] ]
}
respond("Five factorial is " +
(function(x) {
if ( x<2 ) return x;
return x * arguments.callee(x - 1);
})(5)
);
});

216. Plack::App::URLMap
Multiplex multiple apps
Integrated with Builder DSL

217. use CatApp;
use CGIApp;
my $c1 = sub { CatApp->run };
my $c2 = sub { CGIApp->run_psgi };
use Plack::Builder;
return builder {
mount “/cat” => $c1;
mount “/cgi-app” => builder {
enable “StackTrace”;
$c2;
};
}

218. use CatApp;
use CGIApp;
my $c1 = sub { CatApp->run };
my $c2 = sub { CGIApp->run_psgi };
use Plack::Builder;
return builder {
mount “/cat” => $c1;
mount “/cgi-app” => builder {
enable “StackTrace”;
$c2;
};
}

219. use CatApp;
use CGIApp;
my $c1 = sub { CatApp->run };
my $c2 = sub { CGIApp->run_psgi };
use Plack::Builder;
return builder {
mount “/cat” => $c1;
mount “/cgi-app” => builder {
enable “StackTrace”;
$c2;
};
}

220. Some more demos...

221. Basic website

222. TemplateToolkit +
Static

223. my $root = '/path/to/html_doc_root';
my $app = Plack::Middleware::TemplateToolkit->new(
INCLUDE_PATH => root,
)->to_app;
return builder {
enable 'Static',
path =>
qr{.[gif|png|jpg|swf|ico|mov|mp3|pdf|js|css]$},
root => $root;
$app;
}

224. my $root = '/path/to/html_doc_root';
my $app = Plack::Middleware::TemplateToolkit->new(
INCLUDE_PATH => root,
)->to_app;
return builder {
enable 'Static',
path =>
qr{.[gif|png|jpg|swf|ico|mov|mp3|pdf|js|css]$},
root => $root;
$app;
}

225. my $root = '/path/to/html_doc_root';
my $app = Plack::Middleware::TemplateToolkit->new(
INCLUDE_PATH => root,
)->to_app;
return builder {
enable 'Static',
path =>
qr{.[gif|png|jpg|swf|ico|mov|mp3|pdf|js|css]$},
root => $root;
$app;
}

226. my $root = '/path/to/html_doc_root';
my $app = Plack::Middleware::TemplateToolkit->new(
INCLUDE_PATH => root,
)->to_app;
return builder {
enable 'Static',
path =>
qr{.[gif|png|jpg|swf|ico|mov|mp3|pdf|js|css]$},
root => $root;
$app;
}

227. my $root = '/path/to/html_doc_root';
my $app = Plack::Middleware::TemplateToolkit->new(
INCLUDE_PATH => root,
)->to_app;
return builder {
enable 'Static',
path =>
qr{.[gif|png|jpg|swf|ico|mov|mp3|pdf|js|css]$},
root => $root;
$app;
}

228. Creating utilities

229. Caching Proxy

230. Website

231. Website
Developing code

232. Website
Developing code

233. Slow website
Website
Developing code

234. Slow website
Developing code

235. Slow website
Caching Proxy
Developing code

236. use Plack::Middleware::Cache;
use Plack::App::Proxy;
my $app
= Plack::App::Proxy->new(
remote => "http://london.pm.org/" )->to_app;
return builder {
enable "Cache",
match_url => '^/.*', # everything
cache_dir => '/tmp/plack-cache';
$app;
};

237. use Plack::Middleware::Cache;
use Plack::App::Proxy;
my $app
= Plack::App::Proxy->new(
remote => "http://london.pm.org/" )->to_app;
return builder {
enable "Cache",
match_url => '^/.*', # everything
cache_dir => '/tmp/plack-cache';
$app;
};

238. use Plack::Middleware::Cache;
use Plack::App::Proxy;
my $app
= Plack::App::Proxy->new(
remote => "http://london.pm.org/" )->to_app;
return builder {
enable "Cache",
match_url => '^/.*', # everything
cache_dir => '/tmp/plack-cache';
$app;
};

242. use LWP::Simple;
my $content = get(‘http://localhost:5000/’);

243. Caching Proxy +
Domain hijack

244. use LWP::Simple;
my $content = get(‘http://localhost:5000/’);

245. use LWP::Simple;
my $content = get(‘http://london.pm.org/’);

246. my $app
= Plack::App::Proxy->new(
remote => "http://london.pm.org/" )->to_app;
return builder {
enable "Cache",
match_url => '^/.*', # everything
cache_dir => '/tmp/plack-cache2';
$app;
};

247. my $app
= Plack::App::Proxy->new(
remote => "http://london.pm.org/" )->to_app;
return builder {
enable "Cache",
match_url => '^/.*', # everything
cache_dir => '/tmp/plack-cache2';
$app;
};

248. my $app
= Plack::App::Proxy->new(
remote => "http://london.pm.org/" )->to_app;
$app = builder {
enable "Cache",
match_url => '^/.*', # everything
cache_dir => '/tmp/plack-cache2';
$app;
};

249. # Hijack Any LWP::Useragent requests
LWP::Protocol::PSGI->register($app);
use LWP::Simple;
my $content = get("http://london.pm.org/");
say 'o/' if $content =~ /London Perl Mongers/;

250. # Hijack Any LWP::Useragent requests
LWP::Protocol::PSGI->register($app);
use LWP::Simple;
my $content = get("http://london.pm.org/");
say 'o/' if $content =~ /London Perl Mongers/;

251. # Hijack Any LWP::Useragent requests
LWP::Protocol::PSGI->register($app);
use LWP::Simple;
my $content = get("http://london.pm.org/");
say 'o/' if $content =~ /London Perl Mongers/;

252. # Hijack Any LWP::Useragent requests
LWP::Protocol::PSGI->register($app);
use LWP::Simple;
my $content = get("http://london.pm.org/");
say 'o/' if $content =~ /London Perl Mongers/;

256. Plack::Test
Unified interface to write TAP tests
with Mock HTTP and Live HTTP

257. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

258. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

259. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

260. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

261. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

262. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

263. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

264. use Plack::Test;
use HTTP::Request::Common;
my $app = sub {
my $env = shift;
return [ $status, $header, $body ];
};
test_psgi
app => $app,
client => sub {
my $callback = shift;
my $req = GET “http://localhost/foo”;
my $res = $callback->($req);
ok $res->[0] == ‘200’, ‘Success’;
};

265. Test::WWW::Mechanize::PSGI

266. use Test::WWW::Mechanize::PSGI;
my $mech =
Test::WWW::Mechanize::PSGI->new(
app => $app,
);
$mech->get_ok('/');

267. use Test::WWW::Mechanize::PSGI;
my $mech =
Test::WWW::Mechanize::PSGI->new(
app => $app,
);
$mech->get_ok('/');

268. Testing your full configuration!

269. Network setup tip

270. Use a reverse proxy

271. Use a reverse proxy
• Sits in front of servers, not clients - “reverse”

272. Use a reverse proxy
• Sits in front of servers, not clients - “reverse”
• Makes servers more efficient

273. Use a reverse proxy
• Sits in front of servers, not clients - “reverse”
• Makes servers more efficient
• Add HTTPS easily

274. Use a reverse proxy
• Sits in front of servers, not clients - “reverse”
• Makes servers more efficient
• Add HTTPS easily
• Makes scaling easier

275. Internet / Users
Webserver App

276. Internet / Users
Webserver App

277. Internet / Users
Webserver App

278. Internet / Users
Webserver App

279. Internet / Users
Reverse Proxy
NGINX Perlbal Pound
Webserver App

280. Internet / Users
Reverse Proxy
NGINX Perlbal Pound
Webserver App

281. Internet / Users
Reverse Proxy
NGINX Perlbal Pound
Webserver App

282. Internet / Users
Reverse Proxy
NGINX Perlbal Pound
Webserver App

283. Internet / Users
Reverse Proxy
NGINX Perlbal Pound
Webserver App

284. Reverse Proxy
NGINX Perlbal Pound
Server

285. Reverse Proxy
NGINX Perlbal Pound
Server 1 Server 2

286. Reverse Proxy
NGINX Perlbal Pound
Server 1 Server 3
Server 2

287. Reverse Proxy
NGINX Perlbal Pound
Server 1 Server 3
Server 2

288. Plack::Middleware::ReverseProxy
Updates
$env->{REMOTE_ADDRESS}

289. Why use Plack?

290. Why use Plack?
‣ Flexibility
‣ Middleware
‣ Apps
‣ Development
‣ Testing
‣ Deployment

291. Flexibility
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona etc

292. Flexibility
• Easy to change webserver (25+!)
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona etc

293. Flexibility
• Easy to change webserver (25+!)
Plack::Handler::* (CGI, FCGI, Apache)
Apache lighttpd HTTP::Server::PSGI mod_psgi Perlbal
Starman Twiggy uWSGI Corona etc
• Starman seems to be used most

294. Middleware

295. Middleware
• Easy to reuse with any PSGI app

296. Middleware
• Easy to reuse with any PSGI app
• Many tools to make your life easy

297. Middleware
• Easy to reuse with any PSGI app
• Many tools to make your life easy
• 160+ on CPAN now

298. App

299. App
• URLMapping / Routing

300. App
• URLMapping / Routing
• Static files

301. App
• URLMapping / Routing
• Static files
• Proxying

302. Development

303. Development
• plackup

304. Development
• plackup
• Restarter (monitor changes on disk)

305. Development
• plackup
• Restarter (monitor changes on disk)
• HTTP::Server::PSGI

306. Development
• plackup
• Restarter (monitor changes on disk)
• HTTP::Server::PSGI
• Debugging middleware

307. Development
• plackup
• Restarter (monitor changes on disk)
• HTTP::Server::PSGI
• Debugging middleware
• Profiler

308. Testing

309. Testing
• Testing your full configuration

310. Testing
• Testing your full configuration
• Test::WWW::Mechanize::PSGI

311. Testing
• Testing your full configuration
• Test::WWW::Mechanize::PSGI
• Plack::Test

312. Deployment

313. Deployment
• No separate configuration files

314. Deployment
• No separate configuration files
• Easy to choose/change webserver

315. Deployment
• No separate configuration files
• Easy to choose/change webserver
• DotCloud etc - cloud deployment

316. Summary

317. Summary
✦ PSGI is an interface, Plack is the code.

318. Summary
✦ PSGI is an interface, Plack is the code.
✦ Many fast PSGI servers.

319. Summary
✦ PSGI is an interface, Plack is the code.
✦ Many fast PSGI servers.
✦ Adapters and tools for frameworks and
webservers.

320. Summary
✦ PSGI is an interface, Plack is the code.
✦ Many fast PSGI servers.
✦ Adapters and tools for frameworks and
webservers.
✦ An amazing amount of middleware

321. Summary
✦ PSGI is an interface, Plack is the code.
✦ Many fast PSGI servers.
✦ Adapters and tools for frameworks and
webservers.
✦ An amazing amount of middleware
✦ Used in many production systems

322. Use Plack

323. Thank you!
Slides: http://slideshare.net/ranguard
http://plackperl.org/
irc://irc.perl.org/#plack