Mojolicious::Lite - Micro Web Framework
# 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;
Mojolicious::Lite is a micro 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.
A simple Hello World application can look 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 { my $self = shift; $self->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.
@ARGV
app->start('cgi');
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
% morbo myapp.pl Server available at http://127.0.0.1:3000.
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.
$self
# /foo get '/foo' => sub { my $self = shift; $self->render(text => 'Hello World!'); };
All GET and POST parameters are accessible via param.
GET
POST
param
# /foo?user=sri get '/foo' => sub { my $self = shift; my $user = $self->param('user'); $self->render(text => "Hello $user!"); };
The stash is used to pass data to templates, which can be inlined in the DATA section.
stash
DATA
# /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 %>.
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); };
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.
url_for
link_to
form_for
# / get '/' => 'index'; # /hello get '/hello'; __DATA__ @@ index.html.ep <%= link_to Hello => 'hello' %>. <%= link_to Reload => 'index' %>. @@ hello.html.ep Hello World!
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'; We've got content! @@ layouts/green.html.ep <!doctype html><html> <head><title><%= title %></title></head> <body><%= content %></body> </html>
Template blocks can be used like normal Perl functions and are always delimited by the begin and end keywords.
begin
end
# /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>
The content_for helper can be used to pass around blocks of captured content.
content_for
# /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 %> We've got content! <% 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>
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 %>.
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"); }; # /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"); };
Wildcard placeholders allow matching absolutely everything, including / and ..
# /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"); };
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 %>.
The easiest way to make placeholders more restrictive are alternatives, you just make a list of possible values.
# /test # /123 any '/:foo' => [foo => [qw/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 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 => [qw/json txt/]] => sub { my $self = shift; return $self->render_json({hello => 'world!'}) if $self->stash('format') eq 'json'; $self->render_text('hello world!'); };
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.
under
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' => sub { shift->render(text => 'bar!') }; # /foo/baz get '/baz' => sub { shift->render(text => 'baz!') }; app->start;
Conditions such as agent and host from Mojolicious::Plugin::HeaderCondition allow even more powerful route constructs.
agent
host
# /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!'); }; # /bar get '/bar' => (host => 'mojolicio.us') => sub { shift->render(text => 'Hello Mojolicious!'); };
However you might want to disable automatic route caching in case there are routes responding to the same path without conditions attached, since those would otherwise get precedence once cached.
app->routes->cache(0);
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.
flash
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><%= title %></title></head> <body><%= content %></body> </html> @@ login.html.ep % layout 'default'; % title 'Login'; <%= 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'; % title 'Welcome'; <% 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.
secret
app->secret('My secret passphrase here!');
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.
multipart/form-data
250KB
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> <%= form_for upload => (method => 'post', enctype => 'multipart/form-data') => 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.
5MB
MOJO_MAX_MESSAGE_SIZE
# Increase limit to 1GB $ENV{MOJO_MAX_MESSAGE_SIZE} = 1073741824;
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); };
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.
templates
# /external any '/external' => sub { my $self = shift; # templates/foo/bar.html.ep $self->render('foo/bar'); };
Static files will be automatically served from the DATA section (even Base 64 encoded) or a public directory if it exists.
public
@@ something.js alert('hello!'); @@ test.txt (base64) dGVzdCAxMjMKbGFsYWxh % mkdir public % mv something.js public/something.js
Testing your application is as easy as creating a t directory and filling it with normal Perl unit tests.
t
use Test::More tests => 3; use Test::Mojo; use FindBin; require "$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.
test
% ./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.
$t->app->log->level('debug');
To disable debug messages later in a production setup you can change the Mojolicious mode, default will be development.
development
% ./myapp.pl --mode production
Mojo::Log messages will be automatically written to a log/$mode.log file if a log directory exists.
log/$mode.log
log
% 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!'); });
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 { 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
You can continue with Mojolicious::Guides now, and don't forget to have fun!
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.
del
my $route = del '/:foo' => sub {...};
Generate route matching only DELETE requests. See also the tutorial above for more argument variations.
DELETE
get
my $route = get '/:foo' => sub {...};
Generate route matching only GET requests. See also the tutorial above for more argument variations.
helper
helper foo => sub {...};
Add a new helper that will be available as a method of the controller object and the application object, as well as a function in ep templates.
ep
# Helper helper add => sub { $_[1] + $_[2] }; # Controller/Application my $result = $self->add(2, 3); # Template <%= add 2, 3 %>
Note that this function is EXPERIMENTAL and might change without warning!
hook
hook after_dispatch => sub {...};
Add hooks to named events, see Mojolicious for a list of all available events. Note that this function is EXPERIMENTAL and might change without warning!
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 plugins, see Mojolicious for a list of all included example plugins.
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.
PUT
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.
WebSocket
Mojolicious::Lite inherits all attributes from Mojolicious.
Mojolicious::Lite inherits all methods from Mojolicious.
Mojolicious, Mojolicious::Guides, http://mojolicio.us.
To install Mojolicious, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Mojolicious
CPAN shell
perl -MCPAN -e shell install Mojolicious
For more information on module installation, please visit the detailed CPAN module installation guide.