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Symfony2 – Franz Jordán 2011
Even though all routes are loaded from a single file, it's common practice to include additional
routing resources from inside the file. See the Including External Routing Resources section for
more information.
Basic Route Configuration
Defining a route is easy, and a typical application will have lots of routes. A basic route consists
of just two parts: the pattern to match and a defaults array:
_welcome:
pattern: /
defaults: { _controller: AcmeDemoBundle:Main:homepage }
This route matches the homepage (/) and maps it to
the AcmeDemoBundle:Main:homepage controller. The _controller string is translated by
Symfony2 into an actual PHP function and executed. That process will be explained shortly in
the Controller Naming Pattern section.
Routing with Placeholders
Of course the routing system supports much more interesting routes. Many routes will contain
one or more named "wildcard" placeholders:
blog_show:
pattern: /blog/{slug}
defaults: { _controller: AcmeBlogBundle:Blog:show }
The pattern will match anything that looks like /blog/*. Even better, the value matching
the {slug}placeholder will be available inside your controller. In other words, if the URL
is /blog/hello-world, a $slug variable, with a value of hello-world, will be available in
the controller. This can be used, for example, to load the blog post matching that string.
The pattern will not, however, match simply /blog. That's because, by default, all placeholders
are required. This can be changed by adding a placeholder value to the defaults array.
Required and Optional Placeholders
To make things more exciting, add a new route that displays a list of all the available blog posts
for this imaginary blog application:
blog_show:
pattern: /blog/{slug}
defaults: { _controller: AcmeBlogBundle:Blog:show }
So far, this route is as simple as possible - it contains no placeholders and will only match the
exact URL /blog. But what if you need this route to support pagination,
where /blog/2 displays the second page of blog entries? Update the route to have a
new {page} placeholder:
blog:
pattern: /blog/{page}
defaults: { _controller: AcmeBlogBundle:Blog:index }
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