Provided by: libmojolicious-perl_4.63+dfsg-1_all 
NAME
Mojolicious::Guides::Routing - Routing
OVERVIEW
This document contains a simple and fun introduction to the Mojolicious router and its
underlying concepts.
CONCEPTS
Essentials every Mojolicious developer should know.
Dispatcher
The foundation of every web framework is a tiny black box connecting incoming requests
with code generating the appropriate response.
GET /user/show/1 -> $self->render(text => 'Sebastian');
This black box is usually called a dispatcher. There are many implementations using
different strategies to establish these connections, but pretty much all are based around
mapping the requests path to some kind of response generator.
/user/show/1 -> $self->render(text => 'Sebastian');
/user/show/2 -> $self->render(text => 'Sara');
/user/show/3 -> $self->render(text => 'Baerbel');
/user/show/4 -> $self->render(text => 'Wolfgang');
While it is very well possible to make all these connections static, it is also rather
inefficient. That's why regular expressions are commonly used to make the dispatch process
more dynamic.
qr!/user/show/(\d+)! -> $self->render(text => $users{$1});
Modern dispatchers have pretty much everything HTTP has to offer at their disposal and can
use many more variables than just the request path, such as request method and headers
like "Host", "User-Agent" and "Accept".
GET /user/show/23 HTTP/1.1
Host: mojolicio.us
User-Agent: Mozilla/5.0 (compatible; Mojolicious; Perl)
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Routes
While regular expressions are quite powerful they also tend to be unpleasant to look at
and are generally overkill for ordinary path matching.
qr!/user/show/(\d+)! -> $self->render(text => $users{$1});
This is where routes come into play, they have been designed from the ground up to
represent paths with placeholders.
/user/show/:id -> $self->render(text => $users{$id});
The only difference between a static path and the route above is the ":id" placeholder.
One or more placeholders can be anywhere in the route.
/user/:action/:id
A fundamental concept of the Mojolicious router is that extracted placeholder values are
turned into a hash.
/user/show/23 -> /user/:action/:id -> {action => 'show', id => 23}
This hash is basically the center of every Mojolicious application, you will learn more
about this later on. Internally routes get compiled to regular expressions, so you can get
the best of both worlds with a little bit of experience.
/user/show/:id -> qr/(?-xism:^\/user\/show/([^\/\.]+))/
A trailing slash is always optional.
/user/show/23/ -> /user/:action/:id -> {action => 'show', id => 23}
Reversibility
One more huge advantage routes have over regular expressions is that they are easily
reversible, extracted placeholders can be turned back into a path at any time.
/sebastian -> /:name -> {name => 'sebastian'}
{name => 'sebastian'} -> /:name -> /sebastian
Every placeholder has a name, even if it's just an empty string.
Generic placeholders
Generic placeholders are the simplest form of placeholders, they use a colon prefix and
match all characters except "/" and ".".
/hello -> /:name/hello -> undef
/sebastian/23/hello -> /:name/hello -> undef
/sebastian.23/hello -> /:name/hello -> undef
/sebastian/hello -> /:name/hello -> {name => 'sebastian'}
/sebastian23/hello -> /:name/hello -> {name => 'sebastian23'}
/sebastian 23/hello -> /:name/hello -> {name => 'sebastian 23'}
All placeholders can be surrounded by parentheses to separate them from the surrounding
text.
/hello -> /(:name)hello -> undef
/sebastian/23hello -> /(:name)hello -> undef
/sebastian.23hello -> /(:name)hello -> undef
/sebastianhello -> /(:name)hello -> {name => 'sebastian'}
/sebastian23hello -> /(:name)hello -> {name => 'sebastian23'}
/sebastian 23hello -> /(:name)hello -> {name => 'sebastian 23'}
The colon prefix is optional for generic placeholders that are surrounded by parentheses.
/iXmojolicious -> /(one)X(two) -> {one => 'i', two => 'mojolicious'}
Relaxed placeholders
Relaxed placeholders are just like generic placeholders, but use a hash prefix and match
all characters except "/".
/hello -> /#name/hello -> undef
/sebastian/23/hello -> /#name/hello -> undef
/sebastian.23/hello -> /#name/hello -> {name => 'sebastian.23'}
/sebastian/hello -> /#name/hello -> {name => 'sebastian'}
/sebastian23/hello -> /#name/hello -> {name => 'sebastian23'}
/sebastian 23/hello -> /#name/hello -> {name => 'sebastian 23'}
Wildcard placeholders
Wildcard placeholders are just like the two placeholders above, but use an asterisk prefix
and match absolutely everything, including "/" and ".".
/hello -> /*name/hello -> undef
/sebastian/23/hello -> /*name/hello -> {name => 'sebastian/23'}
/sebastian.23/hello -> /*name/hello -> {name => 'sebastian.23'}
/sebastian/hello -> /*name/hello -> {name => 'sebastian'}
/sebastian23/hello -> /*name/hello -> {name => 'sebastian23'}
/sebastian 23/hello -> /*name/hello -> {name => 'sebastian 23'}
BASICS
Most commonly used features every Mojolicious developer should know about.
Minimal route
The attribute "routes" in Mojolicious contains a router you can use to generate route
structures, they match in the same order in which they were defined.
# Application
package MyApp;
use Mojo::Base 'Mojolicious';
sub startup {
my $self = shift;
# Router
my $r = $self->routes;
# Route
$r->route('/welcome')->to(controller => 'foo', action => 'welcome');
}
1;
The minimal route above will load and instantiate the class "MyApp::Foo" and call its
"welcome" method.
# Controller
package MyApp::Foo;
use Mojo::Base 'Mojolicious::Controller';
# Action
sub welcome {
my $self = shift;
# Render response
$self->render(text => 'Hello there.');
}
1;
Routes are usually configured in the "startup" method of the application class, but the
router can be accessed from everywhere (even at runtime).
Routing destination
After you start a new route with the method "route" in Mojolicious::Routes, you can also
give it a destination in the form of a hash using the chained method "to" in
Mojolicious::Routes::Route.
# /welcome -> {controller => 'foo', action => 'welcome'}
$r->route('/welcome')->to(controller => 'foo', action => 'welcome');
Now if the route matches an incoming request it will use the content of this hash to try
and find appropriate code to generate a response.
Stash
The generated hash of a matching route is actually the center of the whole Mojolicious
request cycle. We call it the stash, and it persists until a response has been generated.
# /bye -> {controller => 'foo', action => 'bye', mymessage => 'Bye'}
$r->route('/bye')
->to(controller => 'foo', action => 'bye', mymessage => 'Bye');
There are a few stash values with special meaning, such as "controller" and "action", but
you can generally fill it with whatever data you need to generate a response. Once
dispatched the whole stash content can be changed at any time.
sub bye {
my $self = shift;
# Get message from stash
my $msg = $self->stash('mymessage');
# Change message in stash
$self->stash(mymessage => 'Welcome');
}
For a full list of reserved stash values see "stash" in Mojolicious::Controller.
Nested routes
It is also possible to build tree structures from routes to remove repetitive code. A
route with children can't match on its own though, only the actual endpoints of these
nested routes can.
# /foo -> undef
# /foo/bar -> {controller => 'foo', action => 'bar'}
my $foo = $r->route('/foo')->to(controller => 'foo');
$foo->route('/bar')->to(action => 'bar');
The stash is simply inherited from route to route and newer values override old ones.
# /foo -> undef
# /foo/abc -> undef
# /foo/bar -> {controller => 'foo', action => 'bar'}
# /foo/baz -> {controller => 'foo', action => 'baz'}
# /foo/cde -> {controller => 'foo', action => 'abc'}
my $foo = $r->route('/foo')->to(controller => 'foo', action => 'abc');
$foo->route('/bar')->to(action => 'bar');
$foo->route('/baz')->to(action => 'baz');
$foo->route('/cde');
Special stash values
When the dispatcher sees "controller" and "action" values in the stash it will always try
to turn them into a class and method to dispatch to. The "controller" value gets camelized
using "camelize" in Mojo::Util and prefixed with a "namespace" (defaulting to the
applications class). While the action value is not changed at all, because of this both
values are case sensitive.
# Application
package MyApp;
use Mojo::Base 'Mojolicious';
sub startup {
my $self = shift;
# /bye -> {controller => 'foo', action => 'bye'} -> MyApp::Foo->bye
$self->routes->route('/bye')->to(controller => 'foo', action => 'bye');
}
1;
# Controller
package MyApp::Foo;
use Mojo::Base 'Mojolicious::Controller';
# Action
sub bye {
my $self = shift;
# Render response
$self->render(text => 'Good bye.');
}
1;
Controller classes are perfect for organizing code in larger projects. There are more
dispatch strategies, but because controllers are the most commonly used ones they also got
a special shortcut in the form of "controller#action".
# /bye -> {controller => 'foo', action => 'bye', mymessage => 'Bye'}
$r->route('/bye')->to('foo#bye', mymessage => 'Bye');
During camelization "-" gets replaced with "::", this allows multi level "controller"
hierarchies.
# / -> {controller => 'foo-bar', action => 'hi'} -> MyApp::Foo::Bar->hi
$r->route('/')->to('foo-bar#hi');
For security reasons the dispatcher will always check if the "controller" is actually a
subclass of Mojolicious::Controller or Mojo before dispatching to it.
Route to class
You can use the "namespace" stash value to change the namespace of a whole route with all
its children.
# /bye -> MyApp::Controller::Foo::Bar->bye
$r->route('/bye')
->to(namespace => 'MyApp::Controller::Foo::Bar', action => 'bye');
The "controller" is always appended to the "namespace" if available.
# /bye -> MyApp::Controller::Foo::Bar->bye
$r->route('/bye')->to('foo-bar#bye', namespace => 'MyApp::Controller');
# /hey -> MyApp::Controller::Foo::Bar->hey
$r->route('/hey')->to('Foo::Bar#hey', namespace => 'MyApp::Controller');
You can also change the default namespaces for all routes in the application with the
router attribute "namespaces" in Mojolicious::Routes.
$r->namespaces(['MyApp::Controller']);
Route to callback
The "cb" stash value, which won't be inherited by nested routes, can be used to bypass
controllers and execute a callback instead.
$r->route('/bye')->to(cb => sub {
my $self = shift;
$self->render(text => 'Good bye.');
});
This technique is the foundation of Mojolicious::Lite, you can learn more about it from
the included tutorial.
Placeholders and destinations
Extracted placeholder values will simply redefine older stash values if they already
exist.
# /bye -> {controller => 'foo', action => 'bar', mymessage => 'bye'}
# /hey -> {controller => 'foo', action => 'bar', mymessage => 'hey'}
$r->route('/:mymessage')
->to(controller => 'foo', action => 'bar', mymessage => 'hi');
One more interesting effect, if a placeholder is at the end of a route and there is
already a stash value of the same name present, it automatically becomes optional.
# / -> {controller => 'foo', action => 'bar', mymessage => 'hi'}
$r->route('/:mymessage')
->to(controller => 'foo', action => 'bar', mymessage => 'hi');
This is also the case if multiple placeholders are right after another and not separated
by other characters than "/".
# / -> {controller => 'foo', action => 'bar'}
# /users -> {controller => 'users', action => 'bar'}
# /users/list -> {controller => 'users', action => 'list'}
$r->route('/:controller/:action')
->to(controller => 'foo', action => 'bar');
Special stash values like "controller" and "action" can also be placeholders, which is
very convenient especially during development, but should only be used very carefully,
because every controller method becomes a potential route. All uppercase methods as well
as those starting with an underscore are automatically hidden from the router and you can
use "hide" in Mojolicious::Routes to add additional ones.
# Hide "create" method in all controllers
$r->hide('create');
This has already been done for all attributes and methods from Mojolicious::Controller.
More restrictive placeholders
A very easy way to make placeholders more restrictive are alternatives, you just make a
list of possible values.
# /bender -> {controller => 'foo', action => 'bar', name => 'bender'}
# /leela -> {controller => 'foo', action => 'bar', name => 'leela'}
# /fry -> undef
$r->route('/:name', name => [qw(bender leela)])
->to(controller => 'foo', action => 'bar');
You can also adjust the regular expressions behind placeholders to better suit your needs.
Just make sure not to use "^" and "$" or capturing groups "(...)", because placeholders
become part of a larger regular expression internally, "(?:...)" is fine though.
# /23 -> {controller => 'foo', action => 'bar', number => 23}
# /test -> undef
$r->route('/:number', number => qr/\d+/)
->to(controller => 'foo', action => 'bar');
# /23 -> undef
# /test -> {controller => 'foo', action => 'bar', name => 'test'}
$r->route('/:name', name => qr/[a-zA-Z]+/)
->to(controller => 'foo', action => 'bar');
This way you get easily readable routes and the raw power of regular expressions.
Formats
File extensions like ".html" and ".txt" at the end of a route are automatically detected
and stored in the stash value "format".
# /foo -> {controller => 'foo', action => 'bar'}
# /foo.html -> {controller => 'foo', action => 'bar', format => 'html'}
# /foo.txt -> {controller => 'foo', action => 'bar', format => 'txt'}
$r->route('/foo')->to(controller => 'foo', action => 'bar');
This for example allows multiple templates in different formats to share the same code.
# /foo -> {controller => 'foo', action => 'bar'}
# /foo.html -> {controller => 'foo', action => 'bar', format => 'html'}
$r->route('/foo')->to(controller => 'foo', action => 'bar');
Restrictive placeholders can also be used.
# /foo.rss -> {controller => 'foo', action => 'bar', format => 'rss'}
# /foo.xml -> {controller => 'foo', action => 'bar', format => 'xml'}
# /foo.txt -> undef
$r->route('/foo', format => [qw(rss xml)])
->to(controller => 'foo', action => 'bar');
Or you can just disable format detection, which gets inherited by nested routes and allows
selective re-enabling.
# /foo -> {controller => 'foo', action => 'bar'}
# /foo.html -> undef
$r->route('/foo', format => 0)->to('foo#bar');
# /foo -> {controller => 'foo', action => 'bar'}
# /foo.html -> undef
# /baz -> undef
# /baz.txt -> {controller => 'baz', action => 'yada', format => 'txt'}
# /baz.html -> {controller => 'baz', action => 'yada', format => 'html'}
# /baz.xml -> undef
my $inactive = $r->route(format => 0);
$inactive->route('/foo')->to('foo#bar');
$inactive->route('/baz', format => [qw(txt html)])->to('baz#yada');
Named routes
Naming your routes will allow backreferencing in many methods and helpers throughout the
whole framework, most of them internally rely on "url_for" in Mojolicious::Controller for
this.
# /foo/abc -> {controller => 'foo', action => 'bar', name => 'abc'}
$r->route('/foo/:name')->name('test')
->to(controller => 'foo', action => 'bar');
# Generate URL "/foo/abc" for route "test"
my $url = $self->url_for('test');
# Generate URL "/foo/sebastian" for route "test"
my $url = $self->url_for('test', name => 'sebastian');
# Generate URL "http://127.0.0.1:3000/foo/sebastian" for route "test"
my $url = $self->url_for('test', name => 'sebastian')->to_abs;
Nameless routes get an automatically generated one assigned that is simply equal to the
route itself without non-word characters.
# /foo/bar ("foobar")
$r->route('/foo/bar')->to('test#stuff');
# Generate URL "/foo/bar"
my $url = $self->url_for('foobar');
To refer to the current route you can use the reserved name "current" or no name at all.
# Generate URL for current route
my $url = $self->url_for('current');
my $url = $self->url_for;
To check or get the name of the current route you can use the helper "current_route" in
Mojolicious::Plugin::DefaultHelpers.
# Name for current route
my $name = $self->current_route;
# Check route name in code shared by multiple routes
$self->stash(button => 'green') if $self->current_route('login');
HTTP methods
The method "via" in Mojolicious::Routes::Route allows only specific HTTP methods to pass.
# GET /bye -> {controller => 'foo', action => 'bye'}
# POST /bye -> undef
# DELETE /bye -> undef
$r->route('/bye')->via('GET')->to(controller => 'foo', action => 'bye');
# GET /bye -> {controller => 'foo', action => 'bye'}
# POST /bye -> {controller => 'foo', action => 'bye'}
# DELETE /bye -> undef
$r->route('/bye')->via('GET', 'POST')
->to(controller => 'foo', action => 'bye');
With one small exception, HEAD requests are considered equal to GET and content will not
be sent with the response.
# GET /test -> {controller => 'bar', action => 'test'}
# HEAD /test -> {controller => 'bar', action => 'test'}
# PUT /test -> undef
$r->route('/test')->via('GET')->to(controller => 'bar', action => 'test');
WebSockets
With the method "websocket" in Mojolicious::Routes::Route you can restrict access to
WebSocket handshakes, which are normal GET requests with some additional information.
# /echo (WebSocket handshake)
$r->websocket('/echo')->to(controller => 'foo', action => 'echo');
# Controller
package MyApp::Foo;
use Mojo::Base 'Mojolicious::Controller';
# Action
sub echo {
my $self = shift;
$self->on(message => sub {
my ($self, $msg) = @_;
$self->send("echo: $msg");
});
}
1;
The connection gets established when you respond to the WebSocket handshake request with a
101 response status, which happens automatically if you subscribe to an event with "on" in
Mojolicious::Controller or send a message with "send" in Mojolicious::Controller right
away.
Bridges
Bridge routes created with the method "bridge" in Mojolicious::Routes::Route can be used
to share code with multiple nested routes, because unlike normal nested routes, they
always match and result in additional dispatch cycles.
# /foo -> undef
# /foo/bar -> {controller => 'foo', action => 'baz'}
# {controller => 'foo', action => 'bar'}
my $foo = $r->bridge('/foo')->to(controller => 'foo', action => 'baz');
$foo->route('/bar')->to(action => 'bar');
The actual bridge code needs to return a true value or the dispatch chain will be broken,
this makes bridges a very powerful tool for authentication.
# /foo -> undef
# /foo/bar -> {cb => sub {...}}
# {controller => 'foo', action => 'bar'}
my $foo = $r->bridge('/foo')->to(cb => sub {
my $self = shift;
# Authenticated
return 1 if $self->req->headers->header('X-Bender');
# Not authenticated
$self->render(text => "You're not Bender.");
return undef;
});
$foo->route('/bar')->to(controller => 'foo', action => 'bar');
Broken dispatch chains can be continued by calling the method "continue" in
Mojolicious::Controller, this allows for example non-blocking operations to finish before
reaching the next dispatch cycle.
# /foo -> undef
# /foo/bar -> {cb => sub {...}}
# -> {controller => 'foo', action => 'bar'}
my $foo = $r->bridge('/foo')->to(cb => sub {
my $self = shift;
# Wait 3 seconds and then give visitors a 50% chance to continue
Mojo::IOLoop->timer(3 => sub {
# Loser
return $self->render(text => 'No luck.') unless int rand 2;
# Winner
$self->continue;
});
return undef;
});
$foo->route('/bar')->to(controller => 'foo', action => 'bar');
More convenient routes
From the tutorial you should already know Mojolicious::Lite routes, which are in fact just
a small convenience layer around everything described above and accessible through methods
like "get" in Mojolicious::Routes::Route as part of the normal router.
# POST /foo -> {controller => 'foo', action => 'abc'}
$r->post('/foo')->to(controller => 'foo', action => 'abc');
# PATCH /bar -> {controller => 'foo', action => 'bar', test => 23}
$r->patch('/bar')->to('foo#bar', test => 23);
# GET /baz -> {template => 'foo/bar'}
$r->get('/baz')->to(template => 'foo/bar');
# * /yada.txt -> {controller => 'foo', action => 'yada', format => 'txt'}
# * /yada.json -> {controller => 'foo', action => 'yada', format => 'json'}
$r->any('/yada' => [format => [qw(txt json)]])->to('foo#yada');
# GET /foo/bar -> {controller => 'foo', action => 'bar'}
# PUT /foo/baz -> {controller => 'foo', action => 'baz'}
# PATCH /foo -> {controller => 'foo', action => 'yada'}
my $foo = $r->any('/foo')->to('foo#');
$foo->get('/bar')->to('#bar');
$foo->put('/baz')->to('#baz');
$foo->patch->to('#yada');
This makes the process of growing your Mojolicious::Lite prototypes into full Mojolicious
applications very straightforward.
# POST /bar
$r->post('/bar' => sub {
my $self = shift;
$self->render(text => 'Just like a Mojolicious::Lite action.');
});
Even the more abstract concepts are available with methods like "under" in
Mojolicious::Routes::Route.
# GET /yada
# POST /yada
my $yada = $r->under('/yada');
$yada->get(sub {
my $self = shift;
$self->render(text => 'Hello.');
});
$yada->post(sub {
my $self = shift;
$self->render(text => 'Go away.');
});
Hooks
Hooks operate outside the routing system and allow you to extend the framework itself by
sharing code with all requests indiscriminately through "hook" in Mojolicious, which makes
them a very powerful tool especially for plugins.
# Application
package MyApp;
use Mojo::Base 'Mojolicious';
sub startup {
my $self = shift;
# Check all requests for a "/test" prefix
$self->hook(before_dispatch => sub {
my $c = shift;
$c->render(text => 'This request did not reach the router.')
if $c->req->url->path->contains('/test');
});
# These will not be reached if the hook above renders a response
my $r = $self->routes;
$r->get('/welcome')->to('foo#welcome');
$r->post('/bye')->to('foo#bye');
}
1;
Post-processing the response to set additional headers is a very common use.
# Make sure static files are cached
$self->hook(after_static => sub {
my $c = shift;
$c->res->headers->cache_control('max-age=3600, must-revalidate');
});
Same for pre-processing the request.
# Allow "_method" query parameter to override request method
$self->hook(before_dispatch => sub {
my $c = shift;
return unless my $method = $c->req->url->query->param('_method');
$c->req->method($method);
});
Or more advanced extensions to add monitoring to your application.
# Forward exceptions to a web service
$self->hook(after_dispatch => sub {
my $c = shift;
return unless my $e = $c->stash('exception');
$c->ua->post('https://example.com/bugs' => form => {exception => $e});
});
You can even extend much of the core functionality.
# Make controller object available to actions as $_
$self->hook(around_action => sub {
my ($next, $c, $action, $last) = @_;
local $_ = $c;
return $next->();
});
# Pass route name as argument to actions
$self->hook(around_action => sub {
my ($next, $c, $action, $last) = @_;
return $c->$action($c->current_route);
});
For a full list of available hooks see "HOOKS" in Mojolicious.
Shortcuts
You can also add your own shortcuts with "add_shortcut" in Mojolicious::Routes to make
route generation more expressive.
# Simple "resource" shortcut
$r->add_shortcut(resource => sub {
my ($r, $name) = @_;
# Generate "/$name" route
my $resource = $r->route("/$name")->to("$name#");
# Handle POST requests
$resource->post->to('#create')->name("create_$name");
# Handle GET requests
$resource->get->to('#show')->name("show_$name");
# Handle OPTIONS requests
$resource->options(sub {
my $self = shift;
$self->res->headers->allow('POST, GET, OPTIONS');
$self->render(data => '', status => 204);
});
return $resource;
});
# POST /user -> {controller => 'user', action => 'create'}
# GET /user -> {controller => 'user', action => 'show'}
# OPTIONS /user
$r->resource('user');
Shortcuts can lead to anything, routes, bridges or maybe even both. And watch out for
quicksand!
Introspection
The "routes" command can be used from the command line to list all available routes
together with name and underlying regular expressions.
$ ./myapp.pl routes -v
/foo/:name GET fooname ^/foo/([^/\.]+))(?:\.([^/]+)$)?
/bar POST bar ^/bar(?:\.([^/]+)$)?
ADVANCED
Less commonly used and more powerful features.
IRIs
IRIs are handled transparently, that means paths are guaranteed to be unescaped and
decoded from bytes to characters.
# GET /X (unicode snowman) -> {controller => 'foo', action => 'snowman'}
$r->get('/X')->to('foo#snowman');
Rearranging routes
Until the first request has been handled, all routes can still be moved around or even
removed with methods like "add_child" in Mojolicious::Routes::Route and "remove" in
Mojolicious::Routes::Route. Especially for rearranging routes created by plugins this can
be very useful.
# GET /example/show -> {controller => 'example', action => 'show'}
my $show = $r->get('/show')->to('example#show');
$r->any('/example')->add_child($show);
# Nothing
$r->get('/secrets/show')->to('secrets#show')->name('show_secrets');
$r->find('show_secrets')->remove;
To find routes by their name you can use "find" in Mojolicious::Routes::Route.
Conditions
Sometimes you might need a little more power, for example to check the "User-Agent" header
in multiple routes. This is where conditions come into play, they are basically router
plugins.
# Simple "User-Agent" condition
$r->add_condition(
agent => sub {
my ($route, $c, $captures, $pattern) = @_;
# User supplied regular expression
return undef unless $pattern && ref $pattern eq 'Regexp';
# Match "User-Agent" header and return true on success
my $agent = $c->req->headers->user_agent;
return 1 if $agent && $agent =~ $pattern;
# No success
return undef;
}
);
# /firefox_only (Firefox) -> {controller => 'foo', action => 'bar'}
$r->get('/firefox_only')->over(agent => qr/Firefox/)->to('foo#bar');
The method "add_condition" in Mojolicious::Routes registers the new condition in the
router, while "over" in Mojolicious::Routes::Route actually applies it to the route.
Condition plugins
You can also package your conditions as reusable plugins.
# Plugin
package Mojolicious::Plugin::WerewolfCondition;
use Mojo::Base 'Mojolicious::Plugin';
use Astro::MoonPhase;
sub register {
my ($self, $app) = @_;
# Add "werewolf" condition
$app->routes->add_condition(werewolf => sub {
my ($route, $c, $captures, $days) = @_;
# Keep the werewolves out!
return undef if abs(14 - (phase(time))[2]) > ($days / 2);
# It's ok, no werewolf
return 1;
});
}
1;
Now just load the plugin and you are ready to use the condition in all your applications.
# Application
package MyApp;
use Mojo::Base 'Mojolicious';
sub startup {
my $self = shift;
# Plugin
$self->plugin('WerewolfCondition');
# /hideout (keep them out for 4 days after full moon)
$self->routes->get('/hideout')->over(werewolf => 4)
->to(controller => 'foo', action => 'bar');
}
1;
Embedding applications
You can easily embed whole applications simply by using them instead of a controller. This
allows for example the use of the Mojolicious::Lite domain specific language in normal
Mojolicious controllers.
# Controller
package MyApp::Bar;
use Mojolicious::Lite;
# /hello
get '/hello' => sub {
my $self = shift;
my $name = $self->param('name');
$self->render(text => "Hello $name.");
};
1;
With the method "detour" in Mojolicious::Routes::Route which is very similar to "to" in
Mojolicious::Routes::Route, you can allow the route to partially match and use only the
remaining path in the embedded application, the base path will be passed along in the
"path" stash value.
# /foo/*
$r->any('/foo')->detour('bar#', name => 'Mojo');
A minimal embeddable application is nothing more than a subclass of Mojo, containing a
"handler" method accepting Mojolicious::Controller objects.
package MyApp::Bar;
use Mojo::Base 'Mojo';
sub handler {
my ($self, $c) = @_;
$c->res->code(200);
my $name = $c->param('name');
$c->res->body("Hello $name.");
}
1;
You can also just use Mojolicious::Plugin::Mount to mount whole self-contained
applications under a prefix.
use Mojolicious::Lite;
# Whole application mounted under "/prefix"
plugin Mount => {'/prefix' => '/home/sri/myapp.pl'};
# Normal route
get '/' => sub { shift->render(text => 'Hello World!') };
app->start;
Application plugins
Embedding Mojolicious applications is easy, but it gets even easier if you package the
whole thing as a self contained reusable plugin.
# Plugin
package Mojolicious::Plugin::MyEmbeddedApp;
use Mojo::Base 'Mojolicious::Plugin';
sub register {
my ($self, $app) = @_;
# Automatically add route
$app->routes->any('/foo')->detour(app => EmbeddedApp::app());
}
package EmbeddedApp;
use Mojolicious::Lite;
get '/bar' => 'bar';
1;
__DATA__
@@ bar.html.ep
Hello World!
The "app" stash value, which won't be inherited by nested routes, can be used for already
instantiated applications. Now just load the plugin and you're done.
# Application
package MyApp;
use Mojo::Base 'Mojolicious';
sub startup {
my $self = shift;
# Plugin
$self->plugin('MyEmbeddedApp');
}
1;
MORE
You can continue with Mojolicious::Guides now or take a look at the Mojolicious wiki
<http://github.com/kraih/mojo/wiki>, which contains a lot more documentation and examples
by many different authors.
SUPPORT
If you have any questions the documentation might not yet answer, don't hesitate to ask on
the mailing-list <http://groups.google.com/group/mojolicious> or the official IRC channel
"#mojo" on "irc.perl.org".