Laravel Injecting a class into another class in Laravel - php

I am trying to separate functionalities into two classes and I want to Inject one class into another. However, it seems that Laravel can't recognize the second class and it is always null.
namespace App\Services;
use App\Models\Image;
use App\Models\Offer;
class ImagesService {
public function __construct() {
}
function saveImages(iterable $images, Offer $offer): array {
// ... code here !
}
}
And the class to inject in is:
namespace App\Services;
use App\Models\Action;
use App\Models\Offer;
use App\Models\OfferOption;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\DB;
class OffersService {
protected $imagesService;
function __constructor(ImagesService $imgService) {
$this->imagesService = $imgService; //Doesn't work ! $imagesService is always null!
}
function doSomething() {
$this->imagesService->saveImages(....) // Call to a member function saveImages() on null at
}
}

there are several ways to access and use properties from one class to another class.
Create an instance of the class you want to use in the class you want to use.
Use the class you want to use as Trait and call it use in the other class.
Extend the class you want to use to the class you want to use.

Related

PHP 'USE' operator in classes and extended classes

I'm trying to understand how to use USE in base and extended classes. I have searched around but I don't think I have the correct terminology.
Let's say my base class looks like
namespace App\Classes;
use PhpOffice\PhpSpreadsheet\IOFactory;
use PhpOffice\PhpSpreadsheet\Style\Fill;
use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\Chart\Title;
use PhpOffice\PhpSpreadsheet\Chart\Chart;
use PhpOffice\PhpSpreadsheet\Chart\Legend;
use PhpOffice\PhpSpreadsheet\Chart\PlotArea;
use PhpOffice\PhpSpreadsheet\Style\Alignment;
use PhpOffice\PhpSpreadsheet\Chart\DataSeries;
use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
use PhpOffice\PhpSpreadsheet\Chart\DataSeriesValues;
class ExcelReport
{
public $spreadsheet;
public function __construct()
{
$this->spreadsheet = null;
}
}
and then I extended that class
namespace App\Classes;
class MonthlyExcelReport extends ExcelReport
{
public $id;
public function __construct(int $id)
{
parent::__construct();
$this->id = $id;
}
public function build()
{
$reader = IOFactory::createReader('Xlsx');
}
}
What do I have to do to get the call to IOFactory in the extended class to recognize that use PhpOffice\PhpSpreadsheet\IOFactory; is present in the base class?
I currently get this error Class 'App\Classes\Gap\IOFactory' not found and I don't want to have to repeat all of those use statements in the extended class.
TL;DR;
Namespace is there to allow you to have two classes named the same, but in a different namespace.
Imagine the class Animal\Bear\Claw and Machinery\Compactor\Claw, are things possible with namespaces, when we needed ugly class names like Animal_Bear_Claw and Machinery_Compactor_Claw before the introduction of namespaces in PHP.
Now when you instanciate or use those classes, you don't want to allways have to go in the extends and say
new \Animal\Bear\Claw();
You want to be able to say: "I am in the context of an Animal Factory Pattern and will basically act upon the classes under the Animal namespace, not the Machinery's ones"
So you go:
use Animal\Bear\Claw;
new Claw();
Or
use Animal\Bear;
new Bear\Claw();
Or even, with aliases
use Animal\Bear as MyTeddyBear;
new MyTeddyBear\Claw();
And so, inheriting another class from another containing uses, just does nothing, you'll have to repeat your uses, maybe simplifying them, and most likely, not add uses for class you actually do not use in the said class (did you know that good IDE does prompt you about unused use statement present in your classes and help you add the good ones to your use statements?).
The use statement are not like an include like you seems to believe it.
It is just there to say: "thanks to namespaces, I can have multiple classes with the same name, now the class I want to use is actually under the namespace defined by use"
You are not forced to state a full namespace either in your use statements.
For example:
namespace App\Classes;
use PhpOffice\PhpSpreadsheet\IOFactory;
use PhpOffice\PhpSpreadsheet\Worksheet\Worksheet;
class MonthlyExcelReport extends ExcelReport
{
public function __construct()
{
$reader = IOFactory::createReader('Xlsx');
$workSheet = new Worksheet();
}
}
Could be shortened this way:
namespace App\Classes;
use PhpOffice\PhpSpreadsheet; // This means "all the classes that I am going to use, if not in the same namespace as the current class (App\Classes) would come from the namespace PhpOffice\PhpSpreadsheet"
class MonthlyExcelReport extends ExcelReport
{
public function __construct()
{
$reader = PhpSpreadsheet\IOFactory::createReader('Xlsx');
$workSheet = new PhpSpreadsheet\Worksheet\Worksheet();
}
}
Further reading:
https://www.php.net/manual/en/language.namespaces.faq.php
https://www.php.net/manual/en/language.namespaces.rules.php
Use operator is used to "include" a class.
If you don't use "Use" operator, than you can include as "full path".
In your case:
$reader = IOFactory::createReader('Xlsx');
Should be:
$reader = PhpOffice\PhpSpreadsheet\IOFactory::createReader('Xlsx');

Use Imported Classes From Parent Class In a PHP Trait Laravel 5.5

I'm currently working on a PHP trait thay will help me to reuse code in some class controllers that I have using Laravel framework.
I wanted to make the trait methods as dynamic as I could but when trying to access to a class that my parent class imported, I get a Class not found exception.
My class controller is as follows:
namespace App\Http\Controllers\Admin;
use App\Models\ {
Curso,
Leccion,
Diapositiva,
ImagenDiapositiva
};
use App\Traits\TestTrait;
class DiapositivasController extends Controller{
use TestTrait;
public function addRecord(Request $request){
$request->class_name = 'ImagenDiapositiva';
$this->addImage($request);
}
}
My Trait:
namespace App\Traits;
trait TestTrait{
public function addImage($request){
$class_name = $request->class_name;
$diapositiva = new $class_name;
//extra code
}
}
So my doubt is, do I have to include the model classes I want to use inside my Trait again or am I doing something else wrong?
if you use new with a variable class name, you have to use the fully qualified class name. I'm guessing new $class_name is the root cause of the issue here, since $class_name would have to be something like: 'App\Models\ImagenDiapositiva' or whatever the full namespace is. Just have to change the call $request->class_name = 'ImagenDiapositiva'; to reflect the full name of the class.

How to call a trait method with alias

I'm trying to place a trait inside a class called Page. I also need to rename a trait function so that it doesn't clash with an existing class function. I thought I did all this successfully however I get an error that points to the wrong location?!
Call to undefined function App\Pages\Models\myTraitDefaultScope()
I've also tried: MyTrait\defaultScope($query) instead of trying to rename the conflicting function. But I then get the following error:
Call to undefined function App\MyTrait\defaultScope()
Below is the trait and class contained in separate files.
<?php
namespace App;
use Illuminate\Support\Facades\Auth;
trait MyTrait{
public function defaultScope($query){
return $query->where('active', '1')
}
}
.
<?php namespace Modules\Pages\Models;
use Illuminate\Database\Eloquent\Model;
use App\MyTrait;
class Page extends Model {
use MyTrait{
MyTrait::defaultScope as myTraitDefaultScope;
}
public function defaultScope($query){
return myTraitDefaultScope($query);
}
}
I'm not all that awesome at this so please don't shoot if I've got something badly wrong :)
When you 'use' a trait in your class, the class inherits all the methods and properties of the trait, like if it was extending an abstract class or an interface
So, this method of MyTrait:
public function defaultScope($query){
return $query->where('active', '1')
}
will be inherited by your Page class
As you have aliased this method as: myTraitDefaultScope, to call the method you should call it in the same way you would call every other method of the Page class:
public function defaultScope($query){
//call the method of the class
return $this->myTraitDefaultScope($query);
}
As you're using trait. So it points to the current or parent class. Thus, calling any method should be like $this->method($params); syntax.

Unable to access models and helper classes in custom class file laravel 5

I have created a common class in app/Classes/Common.php
but whenever i try to access a model in a class function.
$new_booking_request = BookingRequest::where('host_id','=',Auth::id())
I am getting this error
Class 'App\Models\BookingRequest' not found
Even other classes like Auth, URL and Cookie are not working.
Is there a way to bring all classes in my Common class scope?
You get this issue when your namespace is wrong you or you forgot to namespace.
Since common.php is inside App/Classes, inside Common.php do somethng like this:
<?php namespace App\Classes;
use View, Auth, URL;
class Common {
//class methods
}
Also ensure your model class has the correct namespace, if BookingRequest.php is located inside App\Models then inside BookingRequest.php do this:
<?php namespace App\Models;
BookingRequest extends \Eloquent {
//other definitions
}
Then if you wish to use BookingRequest.php outside its namespace or in another namespace like so:
<?php namespace App\Classes;
use App\Models\BookingRequest;
use View, Auth, URL;
class Common {
//class methods
}
In Laravel 5 everything is namespaced, make sure your class has a proper namespace and that you are calling it using that same namespace you specified.
To include classes in another class make sure that you use the use keyword to import the necessary classes on top of your class definition. Also you can call the class globally with the \. Ex: \Auth, \URL and \Cookie
For the namespace in L5 here is a quick example:
<?php namespace App\Models;
class BookingRequest {
// class definition
}
then when trying to call that class, either call the full namespace path of the function, or include the function.
<?php
class HomeController extends Controller {
public function index()
{
$newBookingRequest = App\Models\BookingRequest::where('host_id','=',Auth::id());
}
}
OR
<?php namespace App\Controllers;
use App\Models\BookingRequest; // Include the class
class HomeController extends Controller {
public function index()
{
$newBookingRequest = BookingRequest::where('host_id','=',Auth::id());
}
}
PS:
Please use camelCase when defining class attributes and methods as this helps for a better code-styling and naming conventions when using the L5 framework.

Is there a shortcut for namespacing singleton classes

My current code is as following:
namespace Libraries;
class_alias('Libraries\ORM', 'ORM');
class ORM
{
public function __construct() {}
static public function someMethod()
{
// do something
}
}
I thought I could shortcut the namespace as you can see above, so I only needed to call the ORM::someMethod(); instead of \Libraries\ORM::someMethod();
(I am using the ORM class in another namespace, lets says 'Project')
Is this possible or what is the right solution?
I know that I could store the class in a global namespace, but then I still need to use the global slash like: \ORM::someMethod();.
Thanks!
Simply alias the classname when you are importing it:
namespace SomethingEntirelyDifferent;
use Libraries\ORM as ORM;
ORM::someMethod();

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