Skip to content
  • About
    • What is Symfony?
    • Community
    • News
    • Contributing
    • Support
  • Documentation
    • Symfony Docs
    • Symfony Book
    • Screencasts
    • Symfony Bundles
    • Symfony Cloud
    • Training
  • Services
    • Platform.sh for Symfony Best platform to deploy Symfony apps
    • SymfonyInsight Automatic quality checks for your apps
    • Symfony Certification Prove your knowledge and boost your career
    • SensioLabs Professional services to help you with Symfony
    • Blackfire Profile and monitor performance of your apps
  • Other
  • Blog
  • Download
sponsored by SensioLabs
  1. Home
  2. Documentation
  3. Routing
  4. How to Define Optional Placeholders
  • Documentation
  • Book
  • Reference
  • Bundles
  • Cloud

How to Define Optional Placeholders

Edit this page

Warning: You are browsing the documentation for Symfony 3.3, which is no longer maintained.

Read the updated version of this page for Symfony 6.3 (the current stable version).

How to Define 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:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
// src/AppBundle/Controller/BlogController.php

// ...
class BlogController extends Controller
{
    // ...

    /**
     * @Route("/blog")
     */
    public function indexAction()
    {
        // ...
    }
}
1
2
3
4
# app/config/routing.yml
blog:
    path:      /blog
    defaults:  { _controller: AppBundle:Blog:index }
1
2
3
4
5
6
7
8
9
10
11
<!-- app/config/routing.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<routes xmlns="http://symfony.com/schema/routing"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://symfony.com/schema/routing
        http://symfony.com/schema/routing/routing-1.0.xsd">

    <route id="blog" path="/blog">
        <default key="_controller">AppBundle:Blog:index</default>
    </route>
</routes>
1
2
3
4
5
6
7
8
9
10
// app/config/routing.php
use Symfony\Component\Routing\RouteCollection;
use Symfony\Component\Routing\Route;

$collection = new RouteCollection();
$collection->add('blog', new Route('/blog', array(
    '_controller' => 'AppBundle:Blog:index',
)));

return $collection;

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:

1
2
3
4
5
6
7
8
9
10
11
// src/AppBundle/Controller/BlogController.php

// ...

/**
 * @Route("/blog/{page}")
 */
public function indexAction($page)
{
    // ...
}
1
2
3
4
# app/config/routing.yml
blog:
    path:      /blog/{page}
    defaults:  { _controller: AppBundle:Blog:index }
1
2
3
4
5
6
7
8
9
10
11
<!-- app/config/routing.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<routes xmlns="http://symfony.com/schema/routing"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://symfony.com/schema/routing
        http://symfony.com/schema/routing/routing-1.0.xsd">

    <route id="blog" path="/blog/{page}">
        <default key="_controller">AppBundle:Blog:index</default>
    </route>
</routes>
1
2
3
4
5
6
7
8
9
10
// app/config/routing.php
use Symfony\Component\Routing\RouteCollection;
use Symfony\Component\Routing\Route;

$collection = new RouteCollection();
$collection->add('blog', new Route('/blog/{page}', array(
    '_controller' => 'AppBundle:Blog:index',
)));

return $collection;

Like the {slug} placeholder before, the value matching {page} will be available inside your controller. Its value can be used to determine which set of blog posts to display for the given page.

But hold on! Since placeholders are required by default, this route will no longer match on simply /blog. Instead, to see page 1 of the blog, you'd need to use the URL /blog/1! Since that's no way for a rich web app to behave, modify the route to make the {page} parameter optional. This is done by including it in the defaults collection:

1
2
3
4
5
6
7
8
9
10
11
// src/AppBundle/Controller/BlogController.php

// ...

/**
 * @Route("/blog/{page}", defaults={"page"=1})
 */
public function indexAction($page)
{
    // ...
}
1
2
3
4
# app/config/routing.yml
blog:
    path:      /blog/{page}
    defaults:  { _controller: AppBundle:Blog:index, page: 1 }
1
2
3
4
5
6
7
8
9
10
11
12
<!-- app/config/routing.xml -->
<?xml version="1.0" encoding="UTF-8" ?>
<routes xmlns="http://symfony.com/schema/routing"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://symfony.com/schema/routing
        http://symfony.com/schema/routing/routing-1.0.xsd">

    <route id="blog" path="/blog/{page}">
        <default key="_controller">AppBundle:Blog:index</default>
        <default key="page">1</default>
    </route>
</routes>
1
2
3
4
5
6
7
8
9
10
11
// app/config/routing.php
use Symfony\Component\Routing\RouteCollection;
use Symfony\Component\Routing\Route;

$collection = new RouteCollection();
$collection->add('blog', new Route('/blog/{page}', array(
    '_controller' => 'AppBundle:Blog:index',
    'page'        => 1,
)));

return $collection;

By adding page to the defaults key, the {page} placeholder is no longer required. The URL /blog will match this route and the value of the page parameter will be set to 1. The URL /blog/2 will also match, giving the page parameter a value of 2. Perfect.

URL Route Parameters
/blog blog {page} = 1
/blog/1 blog {page} = 1
/blog/2 blog {page} = 2

Caution

Of course, you can have more than one optional placeholder (e.g. /blog/{slug}/{page}), but everything after an optional placeholder must be optional. For example, /{page}/blog is a valid path, but page will always be required (i.e. simply /blog will not match this route).

Tip

Routes with optional parameters at the end will not match on requests with a trailing slash (i.e. /blog/ will not match, /blog will match).

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.
TOC
    Version
    We stand with Ukraine.
    Version:
    Code consumes server resources. Blackfire tells you how

    Code consumes server resources. Blackfire tells you how

    Peruse our complete Symfony & PHP solutions catalog for your web development needs.

    Peruse our complete Symfony & PHP solutions catalog for your web development needs.

    Symfony footer

    ↓ Our footer now uses the colors of the Ukrainian flag because Symfony stands with the people of Ukraine.

    Avatar of Eike Send, a Symfony contributor

    Thanks Eike Send for being a Symfony contributor

    1 commit • 23 lines changed

    View all contributors that help us make Symfony

    Become a Symfony contributor

    Be an active part of the community and contribute ideas, code and bug fixes. Both experts and newcomers are welcome.

    Learn how to contribute

    Symfony™ is a trademark of Symfony SAS. All rights reserved.

    • What is Symfony?

      • Symfony at a Glance
      • Symfony Components
      • Case Studies
      • Symfony Releases
      • Security Policy
      • Logo & Screenshots
      • Trademark & Licenses
      • symfony1 Legacy
    • Learn Symfony

      • Symfony Docs
      • Symfony Book
      • Reference
      • Bundles
      • Best Practices
      • Training
      • eLearning Platform
      • Certification
    • Screencasts

      • Learn Symfony
      • Learn PHP
      • Learn JavaScript
      • Learn Drupal
      • Learn RESTful APIs
    • Community

      • SymfonyConnect
      • Support
      • How to be Involved
      • Code of Conduct
      • Events & Meetups
      • Projects using Symfony
      • Downloads Stats
      • Contributors
      • Backers
    • Blog

      • Events & Meetups
      • A week of symfony
      • Case studies
      • Cloud
      • Community
      • Conferences
      • Diversity
      • Documentation
      • Living on the edge
      • Releases
      • Security Advisories
      • SymfonyInsight
      • Twig
      • SensioLabs
    • Services

      • SensioLabs services
      • Train developers
      • Manage your project quality
      • Improve your project performance
      • Host Symfony projects

      Deployed on

    Follow Symfony

    Search by Meilisearch