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NAME

Mojolicious::Lite - Real-time micro web framework

SYNOPSIS

  # Automatically enables "strict", "warnings" and Perl 5.10 features
  use Mojolicious::Lite;

  # Route with placeholder
  get '/:foo' => sub {
    my $self = shift;
    my $foo  = $self->param('foo');
    $self->render(text => "Hello from $foo!");
  };

  # Start the Mojolicious command system
  app->start;

DESCRIPTION

Mojolicious::Lite is a micro real-time web framework built around Mojolicious.

TUTORIAL

A quick example driven introduction to the wonders of Mojolicious::Lite. Most of what you'll learn here also applies to normal Mojolicious applications.

Hello World!

A simple Hello World application can look like this, strict, warnings and Perl 5.10 features are automatically enabled and a few functions imported when you use Mojolicious::Lite, turning your script into a full featured web application.

  #!/usr/bin/env perl
  use Mojolicious::Lite;

  get '/' => sub {
    my $self = shift;
    $self->render(text => 'Hello World!');
  };

  app->start;

Generator

There is also a helper command to generate a small example application.

  $ mojo generate lite_app

Commands

All the normal Mojolicious::Commands are available from the command line. Note that CGI and PSGI environments can usually be auto detected and will just work without commands.

  $ ./myapp.pl daemon
  Server available at http://127.0.0.1:3000.

  $ ./myapp.pl daemon --listen http://*:8080
  Server available at http://127.0.0.1:8080.

  $ ./myapp.pl cgi
  ...CGI output...

  $ ./myapp.pl
  ...List of available commands (or automatically detected environment)...

Start

The app->start call that starts the Mojolicious command system can be customized to override normal @ARGV use.

  app->start('cgi');

Reloading

Your application will automatically reload itself if you start it with the morbo development web server, so you don't have to restart the server after every change.

  $ morbo myapp.pl
  Server available at http://127.0.0.1:3000.

Routes

Routes are basically just fancy paths that can contain different kinds of placeholders. $self is an instance of Mojolicious::Controller containing both the HTTP request and response.

  # /foo
  get '/foo' => sub {
    my $self = shift;
    $self->render(text => 'Hello World!');
  };

GET/POST parameters

All GET and POST parameters are accessible via param.

  # /foo?user=sri
  get '/foo' => sub {
    my $self = shift;
    my $user = $self->param('user');
    $self->render(text => "Hello $user!");
  };

Stash and templates

The stash is used to pass data to templates, which can be inlined in the DATA section.

  # /bar
  get '/bar' => sub {
    my $self = shift;
    $self->stash(one => 23);
    $self->render('baz', two => 24);
  };

  __DATA__

  @@ baz.html.ep
  The magic numbers are <%= $one %> and <%= $two %>.

For more information about templates see also "Embedded Perl" in Mojolicious::Guides::Rendering.

HTTP

Mojo::Message::Request and Mojo::Message::Response give you full access to all HTTP features and information.

  # /agent
  get '/agent' => sub {
    my $self = shift;
    $self->res->headers->header('X-Bender' => 'Bite my shiny metal ass!');
    $self->render(text => $self->req->headers->user_agent);
  };

Route names

All routes can have a name associated with them, this allows automatic template detection and back referencing with url_for, link_to and form_for. Nameless routes get an automatically generated one assigned that is simply equal to the route itself without non-word characters.

  # /
  get '/' => 'index';

  # /hello
  get '/hello';

  __DATA__

  @@ index.html.ep
  <%= link_to Hello => 'hello' %>.
  <%= link_to Reload => 'index' %>.

  @@ hello.html.ep
  Hello World!

Layouts

Templates can have layouts.

  # /with_layout
  get '/with_layout' => sub {
    my $self = shift;
    $self->render('with_layout');
  };

  __DATA__

  @@ with_layout.html.ep
  % title 'Green!';
  % layout 'green';
  Hello World!

  @@ layouts/green.html.ep
  <!doctype html><html>
    <head><title><%= title %></title></head>
    <body><%= content %></body>
  </html>

Blocks

Template blocks can be used like normal Perl functions and are always delimited by the begin and end keywords.

  # /with_block
  get '/with_block' => 'block';

  __DATA__

  @@ block.html.ep
  % my $link = begin
    % my ($url, $name) = @_;
    Try <%= link_to $url => begin %><%= $name %><% end %>!
  % end
  <!doctype html><html>
    <head><title>Sebastians frameworks!</title></head>
    <body>
      %= $link->('http://mojolicio.us', 'Mojolicious')
      %= $link->('http://catalystframework.org', 'Catalyst')
    </body>
  </html>

Captured content

The content_for helper can be used to pass around blocks of captured content.

  # /captured
  get '/captured' => sub {
    my $self = shift;
    $self->render('captured');
  };

  __DATA__

  @@ captured.html.ep
  % layout 'blue', title => 'Green!';
  % content_for header => begin
    <meta http-equiv="Pragma" content="no-cache">
  % end
  Hello World!
  % content_for header => begin
    <meta http-equiv="Expires" content="-1">
  % end

  @@ layouts/blue.html.ep
  <!doctype html><html>
    <head>
      <title><%= title %></title>
      %= content_for 'header'
    </head>
    <body><%= content %></body>
  </html>

Helpers

You can also extend Mojolicious with your own helpers, a list of all built-in ones can be found in Mojolicious::Plugin::DefaultHelpers and Mojolicious::Plugin::TagHelpers.

  # "whois" helper
  helper whois => sub {
    my $self  = shift;
    my $agent = $self->req->headers->user_agent || 'Anonymous';
    my $ip    = $self->tx->remote_address;
    return "$agent ($ip)";
  };

  # /secret
  get '/secret' => sub {
    my $self = shift;
    my $user = $self->whois;
    $self->app->log->debug("Request from $user.");
  };

  __DATA__

  @@ secret.html.ep
  We know who you are <%= whois %>.

Placeholders

Route placeholders allow capturing parts of a request path until a / or . separator occurs, results will be stored by name in the stash and param.

  # /foo/test
  # /foo/test123
  get '/foo/:bar' => sub {
    my $self = shift;
    my $bar  = $self->stash('bar');
    $self->render(text => "Our :bar placeholder matched $bar");
  };

  # /testsomething/foo
  # /test123something/foo
  get '/(:bar)something/foo' => sub {
    my $self = shift;
    my $bar  = $self->param('bar');
    $self->render(text => "Our :bar placeholder matched $bar");
  };

Wildcard placeholders

Wildcard placeholders allow matching absolutely everything, including / and ..

  # /hello/test
  # /hello/test123
  # /hello/test.123/test/123
  get '/hello/*you' => 'groovy';

  __DATA__

  @@ groovy.html.ep
  Your name is <%= $you %>.

HTTP methods

Routes can be restricted to specific request methods.

  # GET /bye
  get '/bye' => sub {
    my $self = shift;
    $self->render(text => 'Bye!');
  };

  # POST /bye
  post '/bye' => sub {
    my $self = shift;
    $self->render(text => 'Bye!');
  };

  # GET|POST|DELETE /bye
  any ['get', 'post', 'delete'] => '/bye' => sub {
    my $self = shift;
    $self->render(text => 'Bye!');
  };

  # * /baz
  any '/baz' => sub {
    my $self   = shift;
    my $method = $self->req->method;
    $self->render(text => "You called /baz with $method");
  };

Optional placeholders

Routes allow default values to make placeholders optional.

  # /hello
  # /hello/Sara
  get '/hello/:name' => {name => 'Sebastian'} => sub {
    my $self = shift;
    $self->render('groovy', format => 'txt');
  };

  __DATA__

  @@ groovy.txt.ep
  My name is <%= $name %>.

Restrictive placeholders

The easiest way to make placeholders more restrictive are alternatives, you just make a list of possible values.

  # /test
  # /123
  any '/:foo' => [foo => ['test', 123]] => sub {
    my $self = shift;
    my $foo  = $self->param('foo');
    $self->render(text => "Our :foo placeholder matched $foo");
  };

All placeholders get compiled to a regex internally, this process can also be easily customized.

  # /1
  # /123
  any '/:bar' => [bar => qr/\d+/] => sub {
    my $self = shift;
    my $bar  = $self->param('bar');
    $self->render(text => "Our :bar placeholder matched $bar");
  };

Just make sure not to use ^ and $ or capturing groups (...), because placeholders become part of a larger regular expression internally, (?:...) is fine though.

Formats

Formats can be automatically detected by looking at file extensions.

  # /detection.html
  # /detection.txt
  get '/detection' => sub {
    my $self = shift;
    $self->render('detected');
  };

  __DATA__

  @@ detected.html.ep
  <!doctype html><html>
    <head><title>Detected!</title></head>
    <body>HTML was detected.</body>
  </html>

  @@ detected.txt.ep
  TXT was detected.

Restrictive placeholders can also be used for format detection.

  # /hello.json
  # /hello.txt
  get '/hello' => [format => ['json', 'txt']] => sub {
    my $self = shift;
    return $self->render_json({hello => 'world!'})
      if $self->stash('format') eq 'json';
    $self->render_text('hello world!');
  };

Content negotiation

For resources with different representations and that require truly RESTful content negotiation you can also use respond_to.

  # /hello (Accept: application/json)
  # /hello (Accept: text/xml)
  # /hello.json
  # /hello.xml
  # /hello?format=json
  # /hello?format=xml
  get '/hello' => sub {
    my $self = shift;
    $self->respond_to(
      json => {json => {hello => 'world'}},
      xml  => {text => '<hello>world</hello>'},
      any  => {data => '', status => 204}
    );
  };

MIME type mappings can be extended or changed easily with "types" in Mojolicious.

  app->types->type(rdf => 'application/rdf+xml');

Under

Authentication and code shared between multiple routes can be realized easily with the under statement. All following routes are only evaluated if the under callback returned a true value.

  use Mojolicious::Lite;

  # Authenticate based on name parameter
  under sub {
    my $self = shift;

    # Authenticated
    my $name = $self->param('name') || '';
    return 1 if $name eq 'Bender';

    # Not authenticated
    $self->render('denied');
    return;
  };

  # / (with authentication)
  get '/' => 'index';

  app->start;
  __DATA__;

  @@ denied.html.ep
  You are not Bender, permission denied!

  @@ index.html.ep
  Hi Bender!

Prefixing multiple routes is another good use for under.

  use Mojolicious::Lite;

  # /foo
  under '/foo';

  # /foo/bar
  get '/bar' => {text => 'foo bar!'};

  # /foo/baz
  get '/baz' => {text => 'foo baz!'};

  # /
  under '/' => {message => 'whatever'};

  # /bar
  get '/bar' => {inline => '<%= $message %> works!'};

  app->start;

You can also group related routes, which allows nesting of multiple under statements.

  use Mojolicious::Lite;

  # Global logic shared by all routes
  under sub {
    my $self = shift;
    return 1 if $self->req->headers->header('X-Bender');
    $self->render(text => "You're not Bender!");
    return;
  };

  # Admin section
  group {

    # Local logic shared only by routes in this group
    under '/admin' => sub {
      my $self = shift;
      return 1 if $self->req->heaers->header('X-Awesome');
      $self->render(text => "You're not awesome enough!");
      return;
    };

    # GET /admin/dashboard
    get '/dashboard' => {text => 'Nothing to see here yet!'};
  };

  # GET /welcome
  get '/welcome' => {text => 'Hi Bender!'};

  app->start;

Conditions

Conditions such as agent and host from Mojolicious::Plugin::HeaderCondition allow even more powerful route constructs.

  # /foo (Firefox)
  get '/foo' => (agent => qr/Firefox/) => sub {
    my $self = shift;
    $self->render(text => 'Congratulations, you are using a cool browser!');
  };

  # /foo (Internet Explorer)
  get '/foo' => (agent => qr/Internet Explorer/) => sub {
    my $self = shift;
    $self->render(text => 'Dude, you really need to upgrade to Firefox!');
  };

  # http://mojolicio.us/bar
  get '/bar' => (host => 'mojolicio.us') => sub {
    my $self = shift;
    $self->render(text => 'Hello Mojolicious!');
  };

Sessions

Signed cookie based sessions just work out of the box as soon as you start using them.

  use Mojolicious::Lite;

  get '/counter' => sub {
    my $self = shift;
    $self->session->{counter}++;
  };

  app->start;
  __DATA__

  @@ counter.html.ep
  Counter: <%= session 'counter' %>

Secret

Note that you should use a custom secret to make signed cookies really secure.

  app->secret('My secret passphrase here!');

File uploads

All files uploaded via multipart/form-data request are automatically available as Mojo::Upload instances. And you don't have to worry about memory usage, because all files above 250KB will be automatically streamed into a temporary file.

  use Mojolicious::Lite;

  any '/upload' => sub {
    my $self = shift;
    if (my $example = $self->req->upload('example')) {
      my $size = $example->size;
      my $name = $example->filename;
      $self->render(text => "Thanks for uploading $size byte file $name.");
    }
  };

  app->start;
  __DATA__

  @@ upload.html.ep
  <!doctype html><html>
    <head><title>Upload</title></head>
    <body>
      % my @attrs = (method => 'POST', enctype => 'multipart/form-data');
      %= form_for upload => @attrs => begin
        %= file_field 'example'
        %= submit_button 'Upload'
      % end
    </body>
  </html>

To protect you from excessively large files there is also a global limit of 5MB by default, which you can tweak with the MOJO_MAX_MESSAGE_SIZE environment variable.

  # Increase limit to 1GB
  $ENV{MOJO_MAX_MESSAGE_SIZE} = 1073741824;

User agent

With Mojo::UserAgent there's a full featured HTTP 1.1 and WebSocket user agent built right in. Especially in combination with Mojo::JSON and Mojo::DOM this can be a very powerful tool.

  get '/test' => sub {
    my $self = shift;
    $self->render(data => $self->ua->get('http://mojolicio.us')->res->body);
  };

WebSockets

WebSocket applications have never been this easy before.

  websocket '/echo' => sub {
    my $self = shift;
    $self->on_message(sub {
      my ($self, $message) = @_;
      $self->send_message("echo: $message");
    });
  };

External templates

External templates will be searched by the renderer in a templates directory.

  # /external
  any '/external' => sub {
    my $self = shift;

    # templates/foo/bar.html.ep
    $self->render('foo/bar');
  };

Static files

Static files will be automatically served from the DATA section (even Base64 encoded) or a public directory if it exists.

  @@ something.js
  alert('hello!');

  @@ test.txt (base64)
  dGVzdCAxMjMKbGFsYWxh

  $ mkdir public
  $ mv something.js public/something.js

Testing

Testing your application is as easy as creating a t directory and filling it with normal Perl unit tests.

  use Test::More tests => 3;
  use Test::Mojo;

  use FindBin;
  require "$FindBin::Bin/../myapp.pl";

  my $t = Test::Mojo->new;
  $t->get_ok('/')->status_is(200)->content_like(qr/Funky!/);

Run all unit tests with the test command.

  $ ./myapp.pl test

To make your tests more noisy and show you all log messages you can also change the application log level directly in your test files.

  $t->app->log->level('debug');

Mode

To disable debug messages later in a production setup you can change the Mojolicious mode, default will be development.

  $ ./myapp.pl --mode production

Logging

Mojo::Log messages will be automatically written to STDERR or a log/$mode.log file if a log directory exists.

  $ mkdir log

For more control the Mojolicious instance can be accessed directly.

  app->log->level('error');
  app->routes->route('/foo/:bar')->via('GET')->to(cb => sub {
    my $self = shift;
    $self->app->log->debug('Got a request for "Hello Mojo!".');
    $self->render(text => 'Hello Mojo!');
  });

Growing

In case a lite app needs to grow, lite and real Mojolicious applications can be easily mixed to make the transition process very smooth.

  package MyApp::Foo;
  use Mojo::Base 'Mojolicious::Controller';

  sub index {
    my $self = shift;
    $self->render(text => 'It works!');
  }

  package main;
  use Mojolicious::Lite;

  get '/bar' => sub {
    my $self = shift;
    $self->render(text => 'This too!');
  };

  app->routes->namespace('MyApp');
  app->routes->route('/foo/:action')->via('GET')->to('foo#index');

  app->start;

There is also a helper command to generate a full Mojolicious example that will let you explore the astonishing similarities between Mojolicious::Lite and Mojolicious applications. Both share about 99% of the same code, so almost everything you learned in this tutorial applies there too. :)

  $ mojo generate app

More

You can continue with Mojolicious::Guides now, and don't forget to have fun!

FUNCTIONS

Mojolicious::Lite implements the following functions.

any

  my $route = any '/:foo' => sub {...};
  my $route = any ['get', 'post'] => '/:foo' => sub {...};

Generate route matching any of the listed HTTP request methods or all. See also the tutorial above for more argument variations.

app

  my $app = app;

The Mojolicious::Lite application.

del

  my $route = del '/:foo' => sub {...};

Generate route matching only DELETE requests. See also the tutorial above for more argument variations.

get

  my $route = get '/:foo' => sub {...};

Generate route matching only GET requests. See also the tutorial above for more argument variations.

group

  group {...};

Start a new route group. Note that this function is EXPERIMENTAL and might change without warning!

helper

  helper foo => sub {...};

Alias for "helper" in Mojolicious.

hook

  hook after_dispatch => sub {...};

Alias for "hook" in Mojolicious.

plugin

  plugin 'SomeThing';

Alias for "plugin" in Mojolicious.

post

  my $route = post '/:foo' => sub {...};

Generate route matching only POST requests. See also the tutorial above for more argument variations.

put

  my $route = put '/:foo' => sub {...};

Generate route matching only PUT requests. See also the tutorial above for more argument variations.

under

  my $route = under sub {...};
  my $route = under '/:foo';

Generate bridge to which all following routes are automatically appended. See also the tutorial above for more argument variations.

websocket

  my $route = websocket '/:foo' => sub {...};

Generate route matching only WebSocket handshakes. See also the tutorial above for more argument variations.

ATTRIBUTES

Mojolicious::Lite inherits all attributes from Mojolicious.

METHODS

Mojolicious::Lite inherits all methods from Mojolicious.

SEE ALSO

Mojolicious, Mojolicious::Guides, http://mojolicio.us.