What About Routing and controllers in Zend framework?

Zend framework - Interview Questions

We will build a very simple inventory system to display our album collection. The home page will list our collection and allow us to add, edit and delete albums. Hence the following pages are required :

Page	Description
Home	This will display the list of albums and provide links to edit and delete them. Also, a link to enable adding new albums will be provided.
Add new album	This page will provide a form for adding a new album.
Edit album	This page will provide a form for editing an album.
Delete album	This page will confirm that we want to delete an album and then delete it.

Before we set up our files, it's important to understand how the framework expects the pages to be organised. Each page of the application is known as an action and actions are grouped into controllers within modules. Hence, you would generally group related actions into a controller; for instance, a news controller might have actions of current, archived, and view.

As we have four pages that all apply to albums, we will group them in a single controller AlbumController within our Album module as four actions. The four actions will be :

Page	Controller	Action
Home	`AlbumController`	`index`
Add new album	`AlbumController`	`add`
Edit album	`AlbumController`	`edit`
Delete album	`AlbumController`	`delete`

The mapping of a URL to a particular action is done using routes that are defined in the module’s module.config.php file. We will add a route for our album actions. This is the updated module config file with the new code highlighted using comments.

namespace Album;

use Zend\Router\Http\Segment;
use Zend\ServiceManager\Factory\InvokableFactory;

return [
    'controllers' => [
        'factories' => [
            Controller\AlbumController::class => InvokableFactory::class,
        ],
    ],

    // The following section is new and should be added to your file:
    'router' => [
        'routes' => [
            'album' => [
                'type'    => Segment::class,
                'options' => [
                    'route' => '/album[/:action[/:id]]',
                    'constraints' => [
                        'action' => '[a-zA-Z][a-zA-Z0-9_-]*',
                        'id'     => '[0-9]+',
                    ],
                    'defaults' => [
                        'controller' => Controller\AlbumController::class,
                        'action'     => 'index',
                    ],
                ],
            ],
        ],
    ],

    'view_manager' => [
        'template_path_stack' => [
            'album' => __DIR__ . '/../view',
        ],
    ],
];

The name of the route is ‘album’ and has a type of ‘segment’. The segment route allows us to specify placeholders in the URL pattern (route) that will be mapped to named parameters in the matched route. In this case, the route is /album[/:action[/:id]] which will match any URL that starts with /album. The next segment will be an optional action name, and then finally the next segment will be mapped to an optional id. The square brackets indicate that a segment is optional. The constraints section allows us to ensure that the characters within a segment are as expected, so we have limited actions to starting with a letter and then subsequent characters only being alphanumeric, underscore, or hyphen. We also limit the id to digits.

This route allows us to have the following URLs :

URL	Page	Action
`/album`	Home (list of albums)	`index`
`/album/add`	Add new album	`add`
`/album/edit/2`	Edit album with an id of 2	`edit`
`/album/delete/4`	Delete album with an id of 4	`delete`