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;
        my $foo  = $self->param('foo');
        $self->render(text => "Hello from $foo!");
    };

    # Start the Mojolicious command system
    app->start;

DESCRIPTION

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

A minimal Hello World application looks like this, strict and warnings 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 { shift->render(text => 'Hello World!') };

    app->start;

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

    % mojo 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 cgi
    ...CGI output...

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

    % ./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.

    app->start('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 => 'Hello World!');
    };

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. Names are always the last argument, the value * means that the name is simply equal to the route without non-word characters.

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

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

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

    __DATA__

    @@ index.html.ep
    <%= link_to Foo => 'foo' %>.
    <%= link_to Bar => 'bar' %>.

    @@ 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>

Template blocks can be reused like functions in Perl scripts.

    # GET /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://mojolicious.org', 'Mojolicious') %>
            <%== $link->('http://catalystframework.org', 'Catalyst') %>
        </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
    <!doctype html><html>
        <head>
            <%= content header => begin %>
                <title>Hi!</title>
            <% end %>
        </head>
        <body>
            <%= content body => begin %>
                First page!
            <% end %>
        </body>
    </html>

    @@ second.html.ep
    % extends 'first';
    <% content header => begin %>
        <title>Howdy!</title>
    <% end %>
    <% content body => begin %>
        Second page!
    <% end %>

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

    # /*something/foo (everything except "/" and ".")
    # /test/foo
    # /test123/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.

    # /*/hello (everything except "/")
    # /test/hello
    # /test123/hello
    # /test.123/hello
    get '/(.you)/hello' => sub {
        shift->render('groovy');
    };

    __DATA__

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

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

    # /hello/* (everything)
    # /hello/test
    # /hello/test123
    # /hello/test.123/test/123
    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 '/test' => sub {
        my $self = shift;

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

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

    app->start;
    __DATA__

    @@ index.html.ep
    % layout 'funky';
    Who is groovy?
    <%= form_for test => (method => 'post') => begin %>
        <%= text_field 'groovy' %>
        <%= submit_button 'Woosh!' %>
    <% end %>

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

    @@ menu.html.ep
    <%= link_to index => begin %>
        Try again
    <% end %>

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

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;
    };

    # GET / (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';

    # GET /foo/bar
    get '/bar' => sub { shift->render(text => 'bar!') };

    # GET /foo/baz
    get '/baz' => sub { shift->render(text => 'baz!') };

    app->start;

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 the next request (unlike stash, which is only available for the current 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';

    app->start;
    __DATA__

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

    @@ login.html.ep
    % layout 'default';
    <%= form_for login => begin %>
        <% if (param 'name') { %>
            <b>Wrong name or password, please try again.</b><br />
        <% } %>
        Name:<br />
        <%= text_field 'name' %><br />
        Password:<br />
        <%= password_field 'pass' %><br />
        <%= submit_button 'Login' %>
    <% end %>

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

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 and Mojo::DOM 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;
        $self->on_message(sub {
            my ($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 DATA section (even Base 64 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 your application is as easy as creating a t directory and filling it with normal Perl unit tests. Some plugins depend on the actual script name, so a test file for the application myapp.pl should be named t/myapp.t.

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

    use FindBin;
    $ENV{MOJO_HOME} = "$FindBin::Bin/../";
    require "$ENV{MOJO_HOME}/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');

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

    % ./myapp.pl --mode production

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(cb => 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');

    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

Have fun!

FUNCTIONS

Mojolicious::Lite implements the following functions.

any

    my $route = any '/:foo' => sub {...};
    my $route = any [qw/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.

get

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

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

plugin

    plugin 'something';
    plugin 'something', foo => 23;
    plugin 'something', {foo => 23};
    plugin 'Foo::Bar';
    plugin 'Foo::Bar', foo => 23;
    plugin 'Foo::Bar', {foo => 23};

Load a plugin.

post

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

Generate route matching only POST 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://mojolicious.org.