How to use an Interface Repository in a Laravel Nova Action? - php

I'm using the Laravel Repository Pattern to manage my resources and I was wondering how can I use an interface inside a Nova Action? Since an Interface cannot be instanciated, I was wondering how I could use my Interfaces within my action?
In my Controller constructor I create my repository and then I'm able to use it within my functions, but I can't figure out how to do the same thing inside a Laravel Action.
Any idea how I could do this?
An example in my Controller
private $myRepository;
public function __construct(
MyRepositoryInterface $myRepository,
)
{
$this->myRepository = $myRepository;
}
And then inside a function I can do something like
public function destroy($id)
{
$this->myRepository->delete($id);
return response()->json( array("message" => "success") );
}
Now in my Nova Action, here's what I'm trying to do
public function handle(ActionFields $fields, Collection $models)
{
foreach ($models as $model)
{
$myRepository = new MyRepositoryInterface(); // This doesn't work obviously
$myRepository->customManipulation($model->id);
$this->markAsFinished($model);
}
}
Any idea how I could use my repositories?
Thanks!

You can do $myRepository = App::make(MyRepositoryInterface::class);, IoC will resolve it and will instantiate a class instance.
I assume you have already bound the class to the interface:
App::bind('MyRepositoryInterface', 'MyRepository');

Related

Laravel singleton not working across controller/ViewComposer

In Laravel, I have a class that I would like to make available to the service controller, make some changes to in the controller action, and then render out with a ViewComposer.
I have done this several times before without issue, but for some reason this time my usual approach is not working - clearly I'm doing something different, and I'm beginning to suspect I've fundamentally misunderstood an aspect of what I am doing.
I have a ServiceProvider with this register() method:
public function register()
{
$this->app->singleton(HelperTest::class, function ($app) {
$pb = new HelperTest();
$pb->test = "jokes on you batman";
return $pb;
});
}
Then in my controller I'm doing the following:
private $helper;
public function __construct(HelperTest $pb)
{
$this->helper = $pb;
$this->helper->test = "hahah";
}
And then I have a viewcomposer doing the following:
private $helper;
public function __construct(HelperTest $pb)
{
$this->helper = $pb;
}
public function compose(View $view)
{
$view->with('output', $this->helper->test);
}
When I call {{ $output }} in the blade view, I expect to see hahah, but instead I get jokes on you batman.
My debugging has shown that all three of these methods are definitely being called. It looks to me like the ViewComposer is for some reason instantiating its own, fresh instance of the class. What am I doing wrong?
Thanks!
Execute php artisan optimize on your console, this will generate an optimized class loader for your application, then check if you can find your class HelperTest registered in services.php inside boostrap/cache. Until HelperTest is not registered there, Laravel IoC can't resolve your class.

Defining methods which can be used in multiple controllers (in short library) in laravel 5

I want to define some methods which can be used in multiple place or multiple controllers. Basically these methods will be like libraries which will perform multiple queries.
My main aim is to avoid writing common logic multiple times by creating some libraries.
Please help me with it.
Thanks in advance :)
Depends what are you trying to do. Here are some options:
By default all your controllers extend App\Http\Controllers\Controller class. Just put all the shared logic between controllers there.
For complex queries to the database you can create a Repository and and inject in the controllers.
class UserRepository {
public function getActiveUsers() {
return Users::with('role')
->where('...')
->someQueryScopes()
->anotherQueryScope()
->yetAnotherScope();
}
}
class SomeController extends Controller {
public function index(UserRepository $repository) {
$users = $repository->getActiveUsers();
return view('users.index')->withUsers($users);
}
}
Yet another option is to create a Service classes for business logic and inject them in the constructor or relevant methods
class UserCreatorService {
public function create($email, $password){
$user = User::create(['email' => $email, 'password' => $password]);
$user->addRole('Subscriber');
Event::fire(new UserWasCreated($user));
return $user;
}
}
class RegisterController extends Controller {
public function store(Request $request, UserCreatorService $service) {
$user = $service->create($request->input('email'), $request->input('password'));
return view('home')->withUser($user);
}
}
it's simple, build your own library in your app folder then create new file MyLibrary.php
namespace App;
Class MyLibrary {
public static function sum($a, $b) {
return $a + $b;
}
}
then create alias in your config/app.php
'MyLibrary' => App\MyLibrary::class,
and finally you can call it in anywhere your controller
$result = MyLibrary::sum(4, 5); // your $result now have value of 9
You can make a folder named lib and inside that a functions.php file and in composer.json
...
"autoload": {
"files": [
"app/lib/functions.php"
],
...
and run composer dump-autoload
Use helper classes and create common functions in them.
Create a folder named helper in app folder and create a helper class in it. And then use that helper class's function in multiple controller or views as you want.

How share code between application controllers using Laravel framework?

What is the best practice for distributing controllers code with Laravel?
Example:
TaskController consumes particulary request and access specific model methods with task list as a result.
OrganisationTaskTreeController consumes different request accessing same methods on Task Entity but also gets OrganisationTree resource with method shared with OrganisationController.
Code:
class TaskController extends BaseController {
public function getTask(Request $request)
{
$_match = [];
if ($request->has('types'))
{
$_match['type'] = ['$in' => $request->get('types')];
}
if ( ! $request->has('group'))
{
throw new InvalidParameter("Undefined group parameter");
}
....
}
class OrganisationTaskTreeController extends BaseController {
public function getOrganizationTree(Request $request)
{
$_match = [];
$_tree = [];
if ($request->has('types'))
{
$_match['type'] = ['$in' => $request->get('types')];
}
if ( ! $request->has('group'))
{
throw new InvalidParameter("Undefined group parameter");
}
if ($request->has('unti'))
{
$_tree['unit'] = $request->get('unit');
}
....
}
}
How not to duplicate this code?
I think Controllers should not be extended by design, because of using methods from many controllers. It will be an overkill.
I'm thinking about:
Traits
HMVC
Controller as Service
or will it be good to make a Respository which consumes $request?
Perhaps you could refactor the code you want to reuse to a method on a base class that the two classes can extend, eg class TaskController extends BaseController, BaseClass. Then you could use the method on every class that extends the BaseClass.
How about a custom request object that you can typehint into whichever method that needs it for that specific validation? https://www.laravel.com/docs/5.2/validation#form-request-validation

Laravel Dependency Injection: When do you have to? When can you mock Facades? Advantages of either method?

I've been using Laravel for a while now and I have been reading a lot about Dependency Injection an testable code. I've come to a point of confusion when talking about Facades and Mocked Objects. I see two patterns:
class Post extends Eloquent {
protected $guarded = array();
public static $rules = array();
}
This is my Post Model. I could run Post::all(); to get all the posts from my blog. Now I want to incorporate it into my controller.
Option #1: Dependency Injection
My first instinct would be to inject the Post model as a dependecy:
class HomeController extends BaseController {
public function __construct(Post $post)
{
$this->post = $post;
}
public function index()
{
$posts = $this->posts->all();
return View::make( 'posts' , compact( $posts );
}
}
My unit test would look like this:
<?php
use \Mockery;
class HomeControllerTest extends TestCase {
public function tearDown()
{
Mockery::close();
parent::tearDown();
}
public function testIndex()
{
$post_collection = new StdClass();
$post = Mockery::mock('Eloquent', 'Post')
->shouldRecieve('all')
->once()
->andReturn($post_collection);
$this->app->instance('Post',$post);
$this->client->request('GET', 'posts');
$this->assertViewHas('posts');
}
}
Option #2: Facade Mocks
class HomeController extends BaseController {
public function index()
{
$posts = Post::all();
return View::make( 'posts' , compact( $posts );
}
}
My unit test would look like this:
<?php
use \Mockery;
class HomeControllerTest extends TestCase {
public function testIndex()
{
$post_collection = new StdClass();
Post::shouldRecieve('all')
->once()
->andReturn($post_collection);
$this->client->request('GET', 'posts');
$this->assertViewHas('posts');
}
}
I understand both methods but I don't understand why I should or when I should use one method over the other. For example, I've tried to use the DI route with the Auth class but it doesn't work so I have to use the Facade Mocks. Any calcification on this issue would be greatly appreciated.
Although you use dependency injection on Option #1, your controller is still coupled with the Eloquent ORM. (Note that i avoid to use the term Model here because in MVC the Model is not just a class or an object but a layer. It's your business logic.).
Dependency Injection allows for Dependency Inversion but they are not the same thing. According to the Dependency Inversion principle both high and low level code should depend on abstractions. In your case the high level code is your controller and the low level code is the Eloquent ORM that fetches data from MySQL, but as you can see none of them depends on abstractions.
As a consequence, you are not able to change your data access layer without affecting your controller. How would you go about changing for example from MySQL to MongoDB or to the File System? To do this you have to use repositories (or whatever you want to call it).
So create a repositories interface that all your concrete repository implementations (MySQL, MongoDB , File System etc.) should implement.
interface PostRepositoriesInterface {
public function getAll();
}
and then create your concrete implementation e.g. for MySQL
class DbPostRepository implements PostRepositoriesInterface {
public function getAll()
{
return Post::all()->toArray();
/* Why toArray()? This is the L (Liskov Substitution) in SOLID.
Any implementation of an abstraction (interface) should be substitutable
in any place that the abstraction is accepted. But if you just return
Post:all() how would you handle the situation where another concrete
implementation would return another data type? Probably you would use an if
statement in the controller to determine the data type but that's far from
ideal. In PHP you cannot force the return data type so this is something
that you have to keep in mind.*/
}
}
Now your controller must type hint the interface and not the concrete implementation. This is what "Code on an interface an not on implementation" is all about. This is Dependency Inversion.
class HomeController extends BaseController {
public function __construct(PostRepositoriesInterface $repo)
{
$this->repo= $repo;
}
public function index()
{
$posts = $this->repo->getAll();
return View::make( 'posts' , compact( $posts ) );
}
}
This way your controller is decoupled from your data layer. It's open for extension but closed for modification. You can switch to MongoDB or to the File System by creating a new concrete implementation of PostRepositoriesInterface (e.g. MongoPostRepository) and change only the binding from (Note that i don't use any namespaces here):
App:bind('PostRepositoriesInterface','DbPostRepository');
to
App:bind('PostRepositoriesInterface','MongoPostRepository');
In an ideal situation your controller should contain only application and not business logic. If you ever find yourself wanting to call a controller from another controller its a sign that you've done something wrong. In this case your controllers contain too much logic.
This also makes testing easier. Now you are able to test your controller without actually hitting the database. Note that a controller test must test only if the controller functions properly which means that the controller calls the right method, gets the results and pass it to the view. At this point you are not testing the validity of the results. This is not controller's responsibility.
public function testIndexActionBindsPostsFromRepository()
{
$repository = Mockery::mock('PostRepositoriesInterface');
$repository->shouldReceive('all')->once()->andReturn(array('foo'));
App::instance('PostRepositoriesInterface', $repository);
$response = $this->action('GET', 'HomeController#index');
$this->assertResponseOk();
$this->assertViewHas('posts', array('foo'));
}
EDIT
If you choose to go with option #1 you can test it like this
class HomeControllerTest extends TestCase {
public function __construct()
{
$this->mock = Mockery::mock('Eloquent', 'Post');
}
public function tearDown()
{
Mockery::close();
}
public function testIndex()
{
$this->mock
->shouldReceive('all')
->once()
->andReturn('foo');
$this->app->instance('Post', $this->mock);
$this->call('GET', 'posts');
$this->assertViewHas('posts');
}
}

Laravel 4 setting up model using the IoC container

I recently watched this video and wanted to change my Laravel controllers so that they had their dependencies managed with Laravel's IoC container. The video talks about creating an interface for a Model and then implementing that interface for the specific data source used.
My question is: when implementing the interface with a class that extends Eloquent and binding that class to the controller so that it is accessible from $this->model, should I also create interfaces and implementations for the Eloquent models which may be returned when calling methods such as $this->model->find($id)? Should there be different classes for the Model and the ModelRepository?
Put it another way: how do I do new Model when my model is in $this->model.
Generally, yes, people doing that pattern (the repository pattern) have an interface which have some methods defined that your app will use:
interface SomethingInterface {
public function find($id);
public function all();
public function paged($offset, $limit);
}
Then you create an implementation of this. If you're using Eloquent, then you can make an Eloquent implementation
use Illuminate\Database\Model;
class EloquentSomething {
protected $something;
public function __construct(Model $something)
{
$this->something = $something;
}
public function find($id)
{
return $this->something->find($id);
}
public function all() { ... }
public function paged($offset, $limit) { ... }
}
Then you make a service provider to put it all together, and add it into app/config/app.php.
use Something; // Eloquent Model
use Namespace\Path\To\EloquentSomething;
use Illuminate\Support\ServiceProvider;
class RepoServiceProvider extends ServiceProvider {
public function register()
{
$app = $this->app;
$app->bind('Namespace/Path/To/SomethingInterface', function()
{
return new EloquentSomething( new Something );
});
}
}
Finally, your controller can use that interface as a type hint:
use Namespace/Path/To/SomethingInterface;
class SomethingController extends BaseController {
protected $something;
public function __construct(SomethingInterface $something)
{
$this->something = $something;
}
public function home() { return $this->something->paged(0, 10); }
}
That should be it. Apologies on any errors, this isn't tested, but is something I do a lot.
Downsides:
More code :D
Upsides:
Able to switch out implementations (instead of EloquentSomething, can use ArraySomething, MongoSomething, whatever), without changing your controller code or any code that uses an implementation of your interface.
Testable - you can mock your Eloquent class and test the repository, or mock your constructor dependency and test your controller
Re-usable - you can App::make() to get the concrete EloquentSomething anywhere in your app and re-use the Something repository anywhere in your code
Repository is a good place to add additional logic, like a layer of cacheing, or even validation rules. Stock mucking about in your controllers.
Finally:, since I likely typed all that out and STILL DIDN'T ANSWER YOUR QUESTION (wtf?!), you can get a new instance of the model using $this->model. Here's an example for creating a new Something:
// Interface:
public function create(array $data);
// EloquentSomething:
public function create(array $data)
{
$something = this->something->newInstance();
// Continue on with creation logic
}
Key is this method, newInstance().
I've used $newModel = $this->model and it's worked for me.

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