Use of service providers within controllers in Laravel 5.2 - php

As for the title I've googled about two hours searching for a efficient answer and read repeatedly the official documentation, but without any step further, considering I'm relatively new to the framework. The doubt arise while searching for a correct way to share some code between controllers and i stumbled in service providers, so:
I've created say a MyCustomServiceProvider;
I've added it to the providers and aliases arrays within the app.php file;
finally I've created a custom helpers class and registered it like:
class MyCustomServiceProvider extends ServiceProvider
{
public function boot()
{
//
}
public function register()
{
$this->app->bind('App\Helpers\Commander', function(){
return new Commander();
});
}
}
So far, however, if I use that custom class within a controller I necessarily need to add the path to it through the use statement:
use App\Helpers\Commander;
otherwise I get a nice class not found exception and obviously my controller does not his job.
I suspect there's something which escapes to me on service providers! :-)

So far, however, if I use that custom class within a controller I
necessarily need to add the path to it through the use statement:
`use App\Helpers\Commander;`
otherwise I get a nice class not found
exception and obviously my controller does not his job.
Yes, that's how it works. If you don't want to use the full name, you can use a Facade instead.
Create the Facade class like this:
class Commander extends Facade
{
protected static function getFacadeAccessor() { return 'commander'; }
}
register the service:
$this->app->singleton('commander', function ($app) {
return new Commander();
});
add the alias to your config/app.php:
'aliases' => [
//...
'Commander' => Path\To\Facades\Commander::class,
//...
],
and use it like a Facade:
\Commander::doStuff();
On why your code still works, even when you remove the bind:
When you type-hint a parameter to a function, and Laravel does not know about the type you want (through binding), Laravel will do its best to create that class for you, if it is possible. So even though you didn't bind the class, Laravel will happily create a instance of that class for you. Where you actually need the binding is when you use interfaces. Usually, you'd not type-hint specific classes but a interface. But Laravel can not create a instance of an interface and pass it to you, so Laravel needs to know how it can construct a class which implements the interface you need. In this case, you'd bind the class (or the closure which creates the class) to the interface.

Related

How do I inject a request into a facade class in Laravel?

So I have the following class that's a facade:
namespace App\Helpers;
use App\Http\Requests\HomepageRequest;
class Params {
public function __construct(HomepageRequest $request) {
}
Then I have the ParamsServiceProvider class which instantiates the facade class on script startup:
public function register()
{
//
App::bind('params', function() {
return new Params();
});
}
edit: here is the actual facade for the Params class
use Illuminate\Support\Facades\Facade;
class Params extends Facade {
protected static function getFacadeAccessor() {
return 'params';
}
}
This all works fine, the class is instantiated properly, however, it doesn't seem to inject the request object in the constructor like it would in a controller class. Is there a way to inject the request into a facade class like you would in a controller? With the current code, I get the following error:
Too few arguments to function App\Helpers\Params::__construct(), 0
passed in /var/www/v4api/html/app/Providers/ParamsServiceProvider.php
on line 21 and exactly 1 expected
I want to avoid having to manually pass the request input into the class and just have it automatically be injected in the constructor. Any help that you guys can give would be appreciated!
Looks like this worked out:
In the ParamsServiceProvider, instead of using App::bind to instantiate the Params class, do this instead:
public function register()
{
App::alias(Params::class, 'params');
}
then the request object will be injected properly into the facade.
The class you've posted isn't actually a Facade - it's just a regular class.
Because you've type-hinted it's dependencies you don't need to tell Laravel how to create an instance of it - it can work it out all by itself.
You can either inject that class into a controller method (where Laravel will new it up for you), or you can call app(App\Helpers\Params::class) and it will return a new instance of the class for you.
Read more on creating facade classes if you want to create an actual facade. Alternatively you can create a realtime facade - where you instead reference Facades\App\Helpers\Params::foo() and Laravel will let you use the method as if you had an instance of that class.
You have a number options here - point the facade straight to the underlying class and let Laravel work out how to build it, explicitly bind it to the container, or use a realtime facade. Let's go through each.
class Params extends Facade
{
protected static function getFacadeAccessor()
{
return \App\Helpers\Params::class;
}
}
This option points the facade straight to the class you intend it to be a facade for and Laravel will work out the rest.
Alternatively, you can keep it as params and instead fix the binding in the container.
The first example use's Laravel's container to make an instance of the class and return it. Laravel can automatically reflect the class and inject it's dependencies.
App::bind('params', function ($app) {
return $app->make(Params::class);
});
The second example explicitly builds the instance the way you desire, which is just additional code for you to maintain.
App::bind('params', function() {
return new Params(new HomepageRequest);
});
The final option - as mentioned in the earlier answer - is to use a realtime facade and skip the manual binding entirely. You can learn more about realtime facades in the docs.

Laravel: Difference between Facades and Aliases

Good day!
The more I read, the more I get confused about this. What is the difference between a Facade and Aliases?
I have this Class:
/app/libraries/Project/Data.php
namespace PJ;
class Data {
// It is much like a data container, with static methods and properties for saving info
}
And the corresponding facade, so I can access by using just PJD:: .
According to some webpage around:
... Laravel Facades are proxies. They wrap around and call functions
on the underlying true implementation of the code. Further, in the
context of a Laravel application, these Facades are accessed by
assigning them to aliases. This use of the Dependency Injection
container allow you to reference something like
Illuminate\Support\Facades\Filesystem by simply calling File.
(http://ryantablada.com/post/proxies-service-locators-alias-facades-and-war)
But, I've also found and successfully tested that adding something like:
__app/config/app.php__
'aliases' => array(
//....,
'PJD' => 'PJ\Data',
),
I can also access my class the same way.
So, what's the difference?
Thanks
EDIT #01
I have created a class named Data in /app/libraries/Project/Data.php
namespace PJ;
class Data {
// It is much like a data container, with static methods and properties for saving info
}
I have a Facade Class for this Class Data /app/libraries/Project/DataFacade.php
use Illuminate\Support\Facades\Facade;
class PJD extends Facade {
protected static function getFacadeAccessor() {
return 'PJData';
}
}
And I have a Service Provider for them: /app/libraries/Project/DataServiceProvider.php
use Illuminate\Support\ServiceProvider;
class DataServiceProvider extends ServiceProvider {
public function register() {
$this->app->singleton('PJData', function() {
return new PJ\Data;
});
}
}
I also have added to /app/config/app.php:
'providers' => array(
// ....
'DataServiceProvider',
),
and in composer.json I've added a psr-4 line to direct PJ namespace to /app/libraries/Project
"psr-4": {
"PJ\\": "app/libraries/Project"
},
By doing all this, I can access my class from anywhere in the project just by PJD:: instead of PJ\Data::.
However, I've also noticed that just by adding to /app/config/app.php
'aliases' => array(
//....,
'PJD' => 'PJ\Data',
),
I get exactly the same result without all that facades and ServiceProviders. So, what's the point of one or another?
Thanks, and sorry for the large post.
Facade and Alias are two totally different concepts.
you can not access PJ\Data\ by PJD:: unless you have setup alias in the service provider while binding.
If you are accessing it, without defining it in config/app.php, then you have set it up in the service provider file itself.
Definition of alias,
used to indicate that a named person is also known or more familiar under another specified name.
It simply means you are giving a different name to the class so that it will be easier to call.
e.g.
if you have a class like this: Foo\Bar\AVeryLongNamespaceClassName\Data, you can just give an alias, (e.g. PJD) and access its methods and properties by this alias.
Note:
Unit testing is an important aspect of why facades work the way that they do. In fact, testability is the primary reason for facades to even exist.

Laravel 4 Add Method to Class (IoC / Namespaces)

I'm trying to figure out how to add a method to a class in a Laravel package, so that all controllers and models that call that class can access the new method. How do I replace this class in the IoC?
This is the package in question, Angel CMS. The package is my creation, so I can modify it if we need to add aliases or anything to accomplish this.
Let's say I want to add a method to this class:
vendor/angel/core/src/models/PageModule.php
Okay, so I copy the class file to here:
app/models/PageModule.php
And then I modify the copied file, adding a namespace and the desired custom_function method:
<?php namespace MyModels;
use Eloquent;
class PageModule extends Eloquent {
protected $table = 'pages_modules';
public static function custom_function()
{
return 'It works!';
}
}
As you can see, I am using the MyModels namespace here.
Then, I run a composer dump-autoload.
Next, I open up my app/routes.php and register the binding and set up a test route:
App::bind('PageModule', function($app) {
return new \MyModels\PageModule;
});
Route::get('test-binding', function() {
return PageModule::custom_function();
});
But, when visiting the test route, I always receive the same error that the method is undefined.
What am I doing wrong here? Thank you in advance for any help.
To Clarify:
I am attempting to replace the class application-wide so that all other classes (controllers/models/etc.) that call PageModule will have access to the custom_function method. Thanks.
To be honest, I'm pretty new to all this IoC, dependency inversion/injection concept too. But I think I've gone through the same struggle before. What I would do, as much as my knowledge allows, is...
Add a constructor to src/controllers/admin/AdminPageController.php:
protected $pageModule;
public function __construct(PageModule $pageModule)
{
$this->pageModule = $pageModule;
}
Then where you did $module = new PageModule in the same file. You replace it with:
$module = $this->pageModule;
The two modifications above makes use of Laravel's IoC to allow injecting a different PageModule object into your controller, instead of strictly creating PageModule in your code.
Now at this point Laravel should know that when it constructs the AdminPageController, it should create a PageModule and inject into the controller for you.
Since your controller now expects a PageModule class, you can no longer do class PageModule extends Eloquent in your app anymore, because even though the name is the same, PHP does not think that it is! You'll need to extend it:
So let's rename your app/models/PageModule.php to app/models/CustomPageModule.php, and in the file change the class to:
class CustomPageModule extends \PageModule {
Up to this point, you also have a CustomPageModule class that is a child of your package's PageModule. All you need to do now is to let Laravel knows that if any controllers ask for PageModule, it should serve the controller with your MyModels\CustomPageModule instead.
So at the top of your app's routes.php file:
App::bind('PageModule', 'MyModels\CustomPageModule');
Your AdminPageController should now be using your CustomPageModule and can use whatever public methods that are in there!
I'm expecting to be editing this answer heavily since this will be quite a long discussion. My first try at answering above isn't the best code you can write, but I hope it takes the least amount of edit to the original code, and then we can work up from there.
Or fast track by reading up articles like http://culttt.com/2013/07/08/creating-flexible-controllers-in-laravel-4-using-repositories
You probably have a alias for the PageModule facade, you should override this alias using your class \MyModels\PageModule in your app/config/app.php file.
Be careful, it seems like you are overwriting the PageModule class instead of extending it. You should probably extend the parent class instead of Eloquent.

How to extend Laravel's Auth Guard class?

I'm trying to extend Laravel's Auth Guard class by one additional method, so I'm able to call Auth::myCustomMethod() at the end.
Following the documentation section Extending The Framework I'm stuck on how to exactly do this because the Guard class itself doesn't have an own IoC binding which I could override.
Here is some code demonstrating what I'm trying to do:
namespace Foobar\Extensions\Auth;
class Guard extends \Illuminate\Auth\Guard {
public function myCustomMethod()
{
// ...
}
}
Now how should I register the extended class Foobar\Extensions\Auth\Guard to be used instead of the original Illuminate\Auth\Guard so I'm able to call Auth::myCustomMethod() the same way as e.g. Auth::check()?
One way would be to replace the Auth alias in the app/config/app.php but I'm not sure if this is really the best way to solve this.
BTW: I'm using Laravel 4.1.
I would create my own UserProvider service that contain the methods I want and then extend Auth.
I recommend creating your own service provider, or straight up extending the Auth class in one of the start files (eg. start/global.php).
Auth::extend('nonDescriptAuth', function()
{
return new Guard(
new NonDescriptUserProvider(),
App::make('session.store')
);
});
This is a good tutorial you can follow to get a better understanding
There is another method you could use. It would involve extending one of the current providers such as Eloquent.
class MyProvider extends Illuminate\Auth\EloquentUserProvider {
public function myCustomMethod()
{
// Does something 'Authy'
}
}
Then you could just extend auth as above but with your custom provider.
\Auth::extend('nonDescriptAuth', function()
{
return new \Illuminate\Auth\Guard(
new MyProvider(
new \Illuminate\Hashing\BcryptHasher,
\Config::get('auth.model')
),
\App::make('session.store')
);
});
Once you've implemented the code you would change the driver in the auth.php config file to use 'nonDescriptAuth`.
Only way to add (and also replace existing functions) is to create copy of Guard.php file in your project and in app/start/global.php add:
require app_path().'/models/Guard.php';
Of course it's ugly method, but I spent over hour to test all possibilities [how to change things stored in Session by Auth] and it always end with error:
... _contruct of class HSGuard requires first parameter to be 'UserProviderInterface' and get 'EloquentUserProvider' ...

IoC and interface binding catch 22

So in trying to implement IoC, DI, etc. in Laravel 4, I've hit a wall. Either I'm misunderstanding something or doing something horribly wrong, not sure which...
So I have a class Person ("business class", not a model or library):
namespace Entities;
use Interfaces\Person as PersonInterface;
class Person implements PersonInterface {...}
a factory which has:
use Interfaces\Person;
...
App::singleton('user', function($app) {
...
$user_object = new Person();
...
});
and in the aliases array:
'Interfaces\Person' => 'Entities\Person'
Problem is that doesn't work because the Person class can't implement its interface because the interface is bound back to the Person class:
Entities\Person cannot implement Entities\Person - it is not an interface
I seem to be caught in a catch 22 of using IoC and interfaces in the application preventing the classes from actually instantiating.
Don't know if it's relevant, but putting
App::bind('Interfaces\Person','Entities\Person');
in the routes.php files doesn't seem to do anything (but putting it in the aliases array does). Surely I'm doing something wrong here. Any ideas?
Maybe I can help. To bind an interface to the IoC, you want to have an interface and an implementation of the interface. It looks like you have that step correct. You also want to create a service provider. More info on that here: http://laravel.com/docs/ioc#service-providers
Remove any bindings you have from the routes.php file. The service provider is what binds the route, and config/app.php registers it in the IoC as described more fully below.
Your service provider might look something like this:
File Name: ServiceProviders/PersonServiceProvider.php
<?php namespace ServiceProviders;
use Illuminate\Support\ServiceProvider;
use Entities\Person;
class PersonServiceProvider extends ServiceProvider {
/**
* Register the binding.
*
* #return void
*/
public function register()
{
$this->app->bind('Interfaces\Person', function()
{
return new Person();
});
}
}
Once the service provider is created, register it in the config/app.php file as follows:
'ServiceProviders\PersonServiceProvider',
Don't use the aliases. This is used for registering the aliases of facades, which is not what you're attempting to do here if I understand your question correctly.
Lastly, to follow the generally accepted Laravel naming conventions, I'd suggest naming the interface file "PersonInterface.php" and its interface "interface PersonInterface." Similarly, the implementation file might be called "EloquentPerson.php" and the "class EloquentPerson extends PersonInterface". This assumes you're using Eloquent. It's similar to what you have, but I think the class and interface names could make it more readable with those small tweaks.

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