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NAME

Mojolicious::Lite - Micro Web Framework

SYNOPSIS

    # Using Mojolicious::Lite will enable "strict" and "warnings"
    use Mojolicious::Lite;

    # Route with placeholder
    get '/:foo' => sub {
        my $self = shift;
        $self->render_text('Yea baby!');
    };

    # Start the Mojolicious command system
    shagadelic;

DESCRIPTION

Mojolicous::Lite is a micro web framework built around Mojolicious.

A minimal application looks like this.

    #!/usr/bin/env perl

    use Mojolicious::Lite;

    get '/' => sub {
        my $self = shift;
        $self->render_text('Yea baby!');
    };

    shagadelic;

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

    % mojolicious generate lite_app

All the normal Mojolicious command options are available from the command line. Note that CGI, FastCGI 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 daemon_prefork
    Server available at http://127.0.0.1:3000.

    % ./myapp.pl cgi
    ...CGI output...

    % ./myapp.pl fastcgi
    ...Blocking FastCGI main loop...

The shagadelic call that starts the Mojolicious command system can be customized to override normal @ARGV use.

    shagadelic('cgi');

Your application will automatically reload itself if you set the --reload option, so you don't have to restart the server after every change.

    % ./myapp.pl daemon --reload
    Server available at http://127.0.0.1:3000.

Routes are basically just fancy paths that can contain different kinds of placeholders.

    # /foo
    get '/foo' => sub {
        my $self = shift;
        $self->render_text('Yea baby!');
    };

All routes can have a name associated with them, this allows automatic template detection and back referencing with url_for. Names are always the last argument.

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

    # /foo
    get '/foo' => 'foo';

    # /bar
    get '/bar' => sub {
        my $self = shift;
        $self->render_text('Hi!')
    } => 'bar';

    __DATA__

    @@ index.html.ep
    <a href="<%= url_for 'foo' %>">Foo</a>.
    <a href="<%= url_for 'bar' %>">Bar</a>.

    @@ foo.html.ep
    <a href="<%= url_for 'index' %>">Home</a>.

Templates can have layouts.

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

    __DATA__

    @@ with_layout.html.ep
    We've got content!

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

Templates can also pass around blocks of captured content and extend each other.

    # GET /
    get '/' => 'first';

    # GET /second
    get '/second' => 'second';

    __DATA__

    @@ first.html.ep
    % extends 'second';
    %{ content header =>
        <title>Howdy!</title>
    %}
    First!

    @@ second.html.ep
    % layout 'third';
    %{ content header =>
        <title>Welcome!</title>
    %}
    Second!

    @@ layouts/third.html.ep
    <!doctype html><html>
        <head>
            <%{= content header => %>
                <title>Lame default title...</title>
            <%}%>
        </head>
        <body><%= content %></body>
    </html>

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/*
    get '/foo/:bar' => sub {
        my $self = shift;
        my $bar  = $self->stash('bar');
        $self->render_text("Our :bar placeholder matched $bar");
    };

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

Relaxed placeholders allow matching of everything until a / occurs.

    # GET /hello/*
    get '/hello/(.you)' => sub {
        shift->render('groovy');
    };

    __DATA__

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

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

    # /hello/*
    get '/hello/(*you)' => sub {
        shift->render('groovy');
    };

    __DATA__

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

Routes can be restricted to specific request methods.

    # GET /bye
    get '/bye' => sub { shift->render_text('Bye!') };

    # POST /bye
    post '/bye' => sub { shift->render_text('Bye!') };

    # GET|POST|DELETE /bye
    any [qw/get post delete/] => '/bye' => sub {
        shift->render_text('Bye!');
    };

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

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

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

Routes allow default values to make placeholders optional.

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

    __DATA__

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

All those features can be easily used together.

    # /everything/*?name=*
    get '/everything/:stuff' => [stuff => qr/\d+/] => {stuff => 23} => sub {
        shift->render('welcome');
    };

    __DATA__

    @@ welcome.html.ep
    Stuff is <%= $stuff %>.
    Query param name is <%= param 'name' %>.

Here's a fully functional example for a html form handling application using multiple features at once.

    #!/usr/bin/env perl

    use Mojolicious::Lite;

    get '/' => 'index';

    post '/form' => sub {
        my $self = shift;

        my $groovy = $self->param('groovy') || 'Austin Powers';
        $groovy =~ s/[^\w\s]+//g;

        $self->render(
            template => 'welcome',
            layout   => 'funky',
            groovy   => $groovy
        );
    } => 'form';

    shagadelic;
    __DATA__

    @@ index.html.ep
    % layout 'funky';
    Who is groovy?
    <form action="<%= url_for 'form' %>" method="POST">
        <input type="text" name="groovy" />
        <input type="submit" value="Woosh!">
    </form>

    @@ welcome.html.ep
    <%= $groovy %> is groovy!
    <%= include 'menu' %>

    @@ menu.html.ep
    <a href="<%= url_for 'index' %>">Try again</a>

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

Ladders can be used for authentication and to share code between multiple routes. All routes following a ladder are only evaluated if the ladder returns a true value.

    use Mojolicious::Lite;

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

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

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

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

    shagadelic;
    __DATA__;

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

    @@ index.html.ep
    Hi Bender!

Conditions such as agent allow even more powerful route constructs.

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

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

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.

Signed cookie based sessions just work out of the box as soon as you start using them. The flash can be used to store values that will only be available for one request, this is very useful in combination with redirect_to.

    use Mojolicious::Lite;

    get '/login' => sub {
        my $self = shift;
        my $name = $self->param('name') || '';
        my $pass = $self->param('pass') || '';
        return $self->render unless $name eq 'sebastian' && $pass eq '1234';
        $self->session(name => $name);
        $self->flash(message => 'Thanks for logging in!');
        $self->redirect_to('index');
    } => 'login';

    get '/' => sub {
        my $self = shift;
        return $self->redirect_to('login') unless $self->session('name');
        $self->render;
    } => 'index';

    get '/logout' => sub {
        my $self = shift;
        $self->session(expires => 1);
        $self->redirect_to('index');
    } => 'logout';

    shagadelic;
    __DATA__

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

    @@ login.html.ep
    % layout 'default';
    <form action="<%= url_for %>">
        <% if (param 'name') { %>
            <b>Wrong name or password, please try again.</b><br />
        <% } %>
        Name:<br />
        <input type="text" name="name" value="<%= param 'name' %>" /><br />
        Password:<br />
        <input type="text" name="pass" value="<%= param 'pass' %>" /><br />
        <input type="submit" value="Login"/>
    </form>

    @@ index.html.ep
    % layout 'default';
    <% if (my $message = flash 'message' ) { %>
        <b><%= $message %></b><br />
    <% } %>
    Welcome <%= session 'name' %>!<br />
    <a href="<%= url_for 'logout' %>">Logout</a>

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

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

A full featured HTTP 1.1 and WebSocket client is built right in. Especially in combination with Mojo::JSON this can be a very powerful tool.

    get '/test' => sub {
        my $self = shift;
        $self->render_data(
            $self->client->get('http://mojolicious.org')->res->body);
    };

WebSocket applications have never been this easy before.

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

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 will be automatically served from the public directory if it exists.

    % 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 like t/funky.t.

    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 less noisy you can also change the application log level directly in your test files.

    app->log->level('error');

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

    % MOJO_MODE=production ./myapp.pl

Log messages will be automatically written to 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(callback => sub {
        my $self = shift;
        $self->render_text('Hello Mojo!');
    });

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

    package MyApp::Foo;
    use base 'Mojolicious::Controller';

    sub index { shift->render_text('It works!') }

    package main;
    use Mojolicious::Lite;

    get '/bar' => sub { shift->render_text('This too!') };

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

    shagadelic;

ATTRIBUTES

Mojolicious::Lite inherits all attributes from Mojolicious.

METHODS

Mojolicious::Lite inherits all methods from Mojolicious.

SEE ALSO

Mojolicious, Mojolicious::Guides, http://mojolicious.org.