Decorate your objects using presenters. Primarily to keep presentation logic out of your models.
Ping me @robboclancy for any urgent issues, github isn't always correctly notifying me.
This library provides a simple class to help make a Presenter
for your objects or arrays. It also has little extras for use within Laravel with minimal extra code in your controllers (in most cases no extra code).
Add robclancy/presenter
to the "require" section of your composer.json
file.
"robclancy/presenter": "1.4.*"
Run composer update
to get the latest version of the package.
It's recommended that you use Composer, however you can download and install from this repository.
This package comes with an optional service provider for Laravel 5.8+ so that you can automate some extra steps. You will need to have installed using the composer method above, then register the service provider with your application.
Open app/config/app.php
and find the providers
key. Add
'Robbo\Presenter\PresenterServiceProvider',
to the array at some point after
'Illuminate\View\ViewServiceProvider',
Now presenters will automatically be created if using the laravel method described below.
Presenter
is a very simple class that overloads methods and variables so that you can add extra logic to your objects or arrays without adding view logic to areas like your models or controllers and also keeps any extra logic out of your views.
Let's say you have a list of users and you want to generate a link to the profile of each user. Many people would just build the URL in the view, or worse, in the controller. To separate this logic we instead use a presenter. Let's assume we have a User
class which simply has an id
and username
property. The presenter might look like this.
class UserPresenter extends Robbo\Presenter\Presenter {
public function url()
{
return $this->id.'-'.$this->username;
}
}
Now our view should receive an instance of this presenter which would be created with something like $user = new UserPresenter(new User);
. If we want to link to the users page all we have to do is call $user->url()
. Now you have good separation of logic and an easy little class you can modify to add properties to your User
in all areas.
However you might not want to be calling methods like this, it could be inconsistent with what you are doing or you might want the code to look a little cleaner. That is where methods with the present
prefix come in. All we do is update the presenter to the following.
class UserPresenter extends Robbo\Presenter\Presenter {
public function presentUrl()
{
return $this->id.'-'.$this->username;
}
}
Now the presenter will call this new method when you execute $user->url
. Further more you can access this method via ArrayAccess
by calling $user['url']
. More on ArrayAccess
support below.
As mentioned in the above section to create a presenter you simply initiate with the new
keyword and inject your object or array.
class User {
// ...
}
class UserPresenter extends Robbo\Presenter\Presenter {
// ...
}
$user = new User;
// handle stuff here
// make sure to "convert" to a presenter before the object gets to your views
$user = new UserPresenter($user);
// Can also create a presenter for arrays
$user = [
'id' => 1,
'username' => 'Robbo',
];
// same as before
$user = new UserPresenter($user);
If you are using laravel and have followed the above installation instructions you can use the provided interface Robbo\Presenter\PresentableInterface
to automate turning your model instances into a Presenter
from both collections and when a model is sent directly to the view.
What the service provider does is extend Laravel's view component with a step before the view object is created. This step turns anything that implements the PresentableInterface
into a Presenter
by calling ->getPresenter()
. What this means is you don't need to add anything extra to your controllers to have your views using presenters for your objects.
For Example.
class UserPresenter extends Robbo\Presenter\Presenter {
// ...
}
class User implements Robbo\Presenter\PresentableInterface {
/**
* Return a created presenter.
*
* @return Robbo\Presenter\Presenter
*/
public function getPresenter()
{
return new UserPresenter($this);
}
}
Now whenever your User
model is sent to a view, in a collection, array or by itself it will be turned into a presenter using the provided getPresenter()
method. So your controller will work with User
and when you get to your view it will be working with UserPresenter
with the internal object being User
.
1.1.x introduces support for arrays. The Presenter
will implement ArrayAccess
so in your views you can access your variables with $presenter['variable']
if you want. But more importantly you can give the Presenter
an array instead of an object. So you can use presenters to work with array data as well as objects.
For example.
$user = [
'id' => 1,
'username' => 'Robbo',
];
class UserPresenter extends Robbo\Presenter\Presenter {
public function presentUrl()
{
// This will work exactly the same as previous examples
return $this->id.'-'.$this->username;
// You can also do this...
return $this['id'].'-'.$this['username'];
}
}
// Now we create a presenter much the same as before
$user = new UserPresenter($user);
// In our views we can use the $user as if it were still an array
echo 'Hello, ', $user['username'];
// Or even treat it like the object that it is
echo 'Hello, ', $user->username;
// And like other examples, we can present the url in the same way
echo 'The URL: ', $user->url;
echo 'And again: ', $user['url'];
As of 1.2.x I have added in a decorator object. This object takes care of turning an object that has PresentableInterface
into a Presenter
.
By default, this is done with Laravel's View
objects. The reasoning behind a new class instead of the previous implementation is so it can be better tested and also to allow you to extend it.
Here is an example of extending the Decorator
so that instead of using the PresentableInterface
and getPresenter()
method you can use a public variable on the object called $presenter
.
Note: these instructions are for Laravel usage.
First extend the decorator...
use Robbo\Presenter\Decorator as BaseDecorator;
class Decorator extends BaseDecorator {
/*
* If this variable implements Robbo\Presenter\PresentableInterface then turn it into a presenter.
*
* @param mixed $value
* @return mixed $value
*/
public function decorate($value)
{
if (is_object($value) and isset($value->presenter))
{
$presenter = $value->presenter;
return new $presenter;
}
return parent::decorate($value);
}
}
To use your new decorator either add the following to start/global.php
or into your own service provider.
// In start/global.php
App::make('presenter.decorator', App::share(function($app)
{
$decorator = new Decorator;
Robbo\Presenter\Presenter::setExtendedDecorator($decorator);
return $decorator;
}));
// In a service provider's 'register' method
$this->app['presenter.decorator'] = $this->app->share(function($app)
{
$decorator = new Decorator;
Robbo\Presenter\Presenter::setExtendedDecorator($decorator);
return $decorator;
});
And that is all there is to it. You can easily automate the creation of presenters to suit your workflow using this method.
- minimum Laravel version is now 5.8
- minimum PHP version is now 7.1
- improved the view factory integration which should be future proof
- added Laravel package discovery, thanks luisdalmolin
- use the contract for the Laravel view factory instead of the concrete class, this fixes incompatibilities with https://github.com/fntneves/laravel-transactional-events
- updated https://github.com/FriendsOfPHP/PHP-CS-Fixer/releases and have it run on tests too
- updated tests to better cover Laravel versions after 5.4 and changed the license to MIT
- updated to work with
laravel 5.4.x
, only actual changes that aren't style or tests - added php-cs-fixer to update the code style
- added examples to have tests for providers in a full app situation
- updated to work with
laravel 5.x
- updated to work with
laravel 4.2.x
, to use in4.1.x
stay on version1.2.*
- moved to PSR-4 and now PHP 5.4+
- small refactor and check
isset
against 'present' methods, thanks BenConstable
- presenters can now be nested, thanks alexwhitman
- added support for using Laravel's
View::with(array here)
, thanks skovachev - added ability to use
isset(...)
andunset(...)
on presenter variables, thanks nsbucky - added a new decorator for creating the presenter objects. This makes it so you can extend what happens when decorating an object easily
- the Presenter class now implements ArrayAccess
- added ability to use an array as your internal data
- fixed bug caused by laravel update
- added smarter converting of presenters from PresentableInterface'd objects
- added object getter
getObject
to retrieve the internal object
- fixed bug caused by laravel update
- Initial Release