jasonlewis / presenter by jasonlewis

A view presenter is an incredibly useful way of decorating objects bound to your views. This allows you to perform view related logic in a sensible place instead of placing it directly in your views, or worse, your models.

There are several other libraries out their that provide similar functionality. This package is merely my preferred implementation as everything is configured in isolation to the object being decorated.

Install

You can install this package using Composer:

$ composer require lewis/presenter

Or in your composer.json:

{
    "require": {
        "lewis/presenter": "0.1.*"
    }
}

Once you've run composer update you'll need to register the service provider in your config/app.php file.

'providers' => [
    Lewis\Presenter\PresenterServiceProvider::class
]

Usage

Configuring Presenters

There's several ways to configure your presenters. First, you can utilize the configuration file, which can be published using the following command:

$ php artisan vendor:publish --provider="Lewis\Presenter\PresenterServiceProvider"

There are no presenters configured by default. The published file merely contains an explanation on how to configure your presenters. You must provide an array of key/value pairs linking your object to its presenter.

return [

    App\User::class => App\Presenters\UserPresenter::class,
    App\Post::class => App\Presenters\PostPresenter::class

];

If you'd prefer you can set an array of presenters directly on the decorator. You might choose do to this from a service provider.

$this->app['decorator']->setBindings([
    \App\User::class => \App\Presenters\UserPresenter::class,
    \App\Post::class => \App\Presenters\PostPresenter::class
]);

Lastly, you can configure presenters one at a time using the register method, again, from within a provider.

$this->app['decorator']->register(\App\User::class, \App\Presenters\UserPresenter::class);

Creating Presenters

A presenter should extend from Lewis\Presenter\AbstractPresenter, however, it is NOT required, but highly recommended, as you'll have access to several methods and magic methods that provide some useful functionality.

I like to keep my presenters within a Presenters folder, however, you may organize things in whichever way you prefer.

namespace App\Presenters;

use Lewis\Presenter\AbstractPresenter;

class UserPresenter extends AbstractPresenter
{

}

If you wish to inject dependencies the only requirements are that you name a parameter $object so that Laravel can correctly inject the bound object and that you call the parent constructor.

namespace App\Presenters;

use App\SomeNamespace\SomeClass;
use Lewis\Presenter\AbstractPresenter;

class UserPresenter extends AbstractPresenter
{
    protected $class;

    public function __construct($object, SomeClass $class)
    {
        $this->class = $class;

        parent::__construct($object);
    }
}

Your presenter can then define methods to perform logic that can be used in your views.

public function prettySlug()
{
    return '/'.ltrim($this->slug, '/');
}

You can reference properties on the wrapped object directly (as above), or by using the $object property.

public function prettySlug()
{
    return '/'.ltrim($this->object->slug, '/');
}

From Within Views

Now that you've configured your presenters and created them, you just need to use them from within your views. It's a simple matter of calling the method or property as you define it.

{{ $post->prettySlug }}

Or:

{{ $post->prettySlug() }}

You can also still access you relations and other model attributes.

{{ $post->title }}

@foreach($post->comments as $comment)
    ...
@endforeach

Enjoy

That's about all there is to it.