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Glen Hinkle
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Mojolicious::Lite - Real-time micro web framework


  # 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


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


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!');



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

  $ mojo generate lite_app


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

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

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

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


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



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


Routes are basically just fancy paths that can contain different kinds of placeholders. $self is a Mojolicious::Controller object 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" in Mojolicious::Controller.

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

Stash and templates

The "stash" in Mojolicious::Controller 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);


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

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


"req" in Mojolicious::Controller and "res" in Mojolicious::Controller 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" in Mojolicious::Controller as well as many helpers like "link_to" in Mojolicious::Plugin::TagHelpers. Nameless routes get an automatically generated one assigned that is simply equal to the route itself without non-word characters.

  # /
  get '/' => sub {
    my $self = shift;
  } => 'index';

  # /hello
  get '/hello';


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

  @@ hello.html.ep
  Hello World!


Templates can have layouts too, you just select one with the helper "layout" in Mojolicious::Plugin::DefaultHelpers and place the result of the current template with the helper "content" in Mojolicious::Plugin::DefaultHelpers.

  # /with_layout
  get '/with_layout' => sub {
    my $self = shift;


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

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


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';


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

Captured content

The helper "content_for" in Mojolicious::Plugin::TagHelpers can be used to pass around blocks of captured content.

  # /captured
  get '/captured' => sub {
    my $self = shift;


  @@ 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>
      <title><%= title %></title>
      %= content_for 'header'
    <body><%= content %></body>


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.");


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


Route placeholders allow capturing parts of a request path until a / or . separator occurs, results are accessible via "stash" in Mojolicious::Controller and "param" in Mojolicious::Controller.

  # /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';


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

HTTP methods

Routes can be restricted to specific request methods.

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

  # PUT /hello
  put '/hello' => sub {
    my $self = shift;
    my $size = length $self->req->body;
    $self->render(text => "You uploaded $size bytes to /hello.");

  any ['GET', 'POST', 'PATCH'] => '/bye' => sub {
    my $self = shift;
    $self->render(text => 'Bye World!');

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


  @@ 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.


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

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


  @@ 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'};


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.");

  # 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.");

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

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



Formats can be automatically detected by looking at file extensions.

  # /detection.html
  # /detection.txt
  get '/detection' => sub {
    my $self = shift;


  @@ detected.html.ep
  <!DOCTYPE html>
    <body>HTML was detected.</body>

  @@ detected.txt.ep
  TXT was detected.

Restrictive placeholders can also be used.

  # /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');

Or you can just disable format detection.

  # /hello
  get '/hello' => [format => 0] => {text => 'No format detection.'};

  # Disable detection and allow the following routes selective re-enabling
  under [format => 0];

  # /foo
  get '/foo' => {text => 'No format detection again.'};

  # /bar.txt
  get '/bar' => [format => 'txt'] => {text => ' Just one format.'};

Content negotiation

For resources with different representations and that require truly RESTful content negotiation you can also use "respond_to" in Mojolicious::Controller.

  # /hello (Accept: application/json)
  # /hello (Accept: text/xml)
  # /hello.json
  # /hello.xml
  # /hello?format=json
  # /hello?format=xml
  get '/hello' => sub {
    my $self = shift;
      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');


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.');


Signed cookie based sessions just work out of the box as soon as you start using them through the helper "session" in Mojolicious::Plugin::DefaultHelpers.

  use Mojolicious::Lite;

  get '/counter' => sub {
    my $self = shift;


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


Note that you should use a custom "secret" in Mojolicious 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 objects. 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;

  # Upload form in DATA section
  get '/' => 'form';

  # Multipart upload handler
  post '/upload' => sub {
    my $self = shift;

    # Check file size
    return $self->render(text => 'File is too big.', status => 200)
      if $self->req->is_limit_exceeded;

    # Process uploaded file
    return $self->redirect_to('form')
      unless my $example = $self->param('example');
    my $size = $example->size;
    my $name = $example->filename;
    $self->render(text => "Thanks for uploading $size byte file $name.");


  @@ form.html.ep
  <!DOCTYPE html>
      %= form_for upload => (enctype => 'multipart/form-data') => begin
        %= file_field 'example'
        %= submit_button 'Upload'
      % end

To protect you from excessively large files there is also a 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 "ua" in Mojolicious::Controller 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);


WebSocket applications have never been this easy before.

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

The event "message" in Mojo::Transaction::WebSocket, which you can subscribe to with "on" in Mojolicious::Controller, will be emitted for every new WebSocket message that is received.

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

Static files

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

  @@ something.js

  @@ test.txt (base64)

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


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;

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.



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

  $ ./myapp.pl -m production


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 object can be accessed directly.

  app->routes->get('/foo/:bar' => sub {
    my $self = shift;
    $self->app->log->debug('Got a request for "Hello Mojo!".');
    $self->render(text => 'Hello Mojo!');


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


Mojolicious::Lite implements the following functions.


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

Generate route with "any" in Mojolicious::Routes::Route, matching any of the listed HTTP request methods or all. See also the tutorial above for more argument variations.


  my $app = app;

The Mojolicious::Lite application.


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

Generate route with "delete" in Mojolicious::Routes::Route, matching only DELETE requests. See also the tutorial above for more argument variations.


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

Generate route with "get" in Mojolicious::Routes::Route, matching only GET requests. See also the tutorial above for more argument variations.


  group {...};

Start a new route group.


  helper foo => sub {...};

Alias for "helper" in Mojolicious.


  hook after_dispatch => sub {...};

Alias for "hook" in Mojolicious.


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

Generate route with "options" in Mojolicious::Routes::Route, matching only OPTIONS requests. See also the tutorial above for more argument variations.


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

Generate route with "patch" in Mojolicious::Routes::Route, matching only PATCH requests. See also the tutorial above for more argument variations.


  plugin 'SomeThing';

Alias for "plugin" in Mojolicious.


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

Generate route with "post" in Mojolicious::Routes::Route, matching only POST requests. See also the tutorial above for more argument variations.


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

Generate route with "put" in Mojolicious::Routes::Route, matching only PUT requests. See also the tutorial above for more argument variations.


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

Generate bridge with "under" in Mojolicious::Routes::Route, to which all following routes are automatically appended. See also the tutorial above for more argument variations.


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

Generate route with "websocket" in Mojolicious::Routes::Route, matching only WebSocket handshakes. See also the tutorial above for more argument variations.


Mojolicious::Lite inherits all attributes from Mojolicious.


Mojolicious::Lite inherits all methods from Mojolicious.


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