Extending SilverStripe method in SS4 - php

I am trying to extend a method of a class but having no luck. I am doing this as part of an upgrade from 3.7 to 4.5. In 3.7 it was working fine without using traits. Reading documentation, i used ‘Extensible’ trait. Now i am getting the following error. Checked all my method access levels. All are public but still gets this error
Fatal error : Access level to SilverStripe\Core\Extensible::defineMethods() must be public (as in class SilverStripe\View\ViewableData)
class MyOpenController extends Controller {
use Extensible;
private static $allowed_actions = array(
'login',
'logout'
);
public function login($data = array()) {
//code here
$this->extend('customFunction');
//more code
}
}
I have an Extension class that has definition for this method.
class MyOpenControllerExtension extends Extension
{
public function customFunction() {
//some code here
}
}
cant seem to get why i am having this error. Can someone please help me figure out what is wrong here.
Thanks
DR

ViewableData in SilverStripe 4 already implements the Extensible, Injectable, and Configurable traits that make up the common foundation you are used to from SilverStripe 3. You only need to add the Extensible trait for custom classes - anything extending Controller or DataObject already has them.
The error you are getting is caused by applying this trait twice in your class's hierarchy. ViewableData applies it, and essentially redefines the defineMethods() method at a public level. When you apply the trait again further down the hierarchy, it tries to define the defineMethods() method again at protected visibility, which is what is causing your error.
Removing use Extensible; from your controller will fix your problem.
Also, ensure you have applied your extension to your controller in YAML config:
# File: app/_config/extensions.yml
MyOpenController:
extensions:
- MyOpenControllerExtension

Related

parent controll in Codeigniter 2.2 project not found

In my CI 2.2 project I want to make my parent controll with app's common functionality for use in all app and for this I create file :
application/libraries/N_Controller.php :
<?php
class N_Controller extends Controller
{
public function __construct()
{
parent::__construct();
}
But on first attempt to use it in file
application/controllers/admin/admin.php
<?php
class Admin extends N_Controller
{
public function __construct()
{
parent::__construct();
I got error:
PHP Fatal error: Class 'N_Controller' not found in /controllers/admin/admin.php on line 3, referer: http://local-ci22.com/admin/hostel/edit/15
I tried to add in application/config/autoload.php file :
$autoload['libraries'] = array( 'AppSmarty', 'AppUtils', 'N_Controller');
But it did not help. Which is the correct way ?
if you want to extend the functionality of a system class. you need to follow this recomendations.
place your extended class in /application/core, be sure that you name it exactly like the name and casing of the class created.
your class should extend from CI_Model or CI_Controller, depending on your needs.
wherever you implement your new class, be sure that you honor the same name casing from your extended class.
you should have configured the $config['subclass_prefix'] on /application/config/config.php. let's say in your case with the value 'N_'
what i can see from your code, you are not extending from CI_Controller and your path seems wrong.
Informative note: the /application/library is used to place classes and libraries from 3rd parties that won't fit into CI schemas.

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 does OpenCart access its library classes?

Im current trying to learn more about the core of OpenCart and how its classes actually work. Im also trying to advance my OOP skills in general as Im still learning in that area, so perhaps theres something obvious that Im not seeing.
Im wondering how a controller file knows how to find the cart class (for example).
E.g.
In catalog/controller/checkout cart there is (obviously with code removed)
class ControllerCheckoutCart extends Controller {
public function index() {
$this->cart->update();
}
}
The Controller class can be found in system/engine/controller.php
update() can be found system/library/cart.
I assumed that in the controller.php there would be a link to the cart class, or an object made from it. (Im basing that on the use of $this->).
So how is the cart class actually found from the controller?
Thank you
Firstly, your ControllerCheckoutCart extends the Controller class, so this is the class we need to focus on. You can find this class in /system/engine/controller.php.
Inside this class, there are two magic methods we are interested in. The first is the __construct, where the "registry" class is loaded (found in /system/engine/registry.php if you're interested in picking that apart - it's very simplistic).
You can think of this as a lookup of all the classes the store uses, such as model files, library files and so on. In the construct, the registry is passed to the controller so it has a reference to it
public function __construct($registry) {
$this->registry = $registry;
}
The second and more important magic method is the __get method. This is called when a classes property doesn't exist, for you to handle it yourself if you wish to do so. OpenCart uses this to try and get the class with that key from the registry
public function __get($key) {
return $this->registry->get($key);
}
So $this->cart in any controller would try to get the object with the key cart from the registry. If you look at the index.php file you will see this is allocated in there
// Cart
$registry->set('cart', new Cart($registry));
ControllerCheckoutCart extends Controller, which means it inherits all the code in Controller which you are not seeing here. Some code in Controller, likely in Controller::__construct, is creating the $this->cart object. Example:
class Controller {
public function __construct() {
$this->cart = new Cart;
}
}
Since this constructor is inherited by all child classes, they construct their own $this->cart as well and have access to it in their own methods.
As mentioned by Jay Gilford, you need to register your newly added library class file in the index.php and/or admin/index.php (depending on if you are using it in catalog or admin)
$registry->set('yourlibraryclass', new YourLibraryClass());
so that upon system loading, Opencart knows that your class exists, then you can call all its functions by:
$this->yourlibraryfilename->function();
Please note that your library file name is normally the same as your class name, hence it is used in the example here.
After the change has been done in the index.php files, you need to logout and login again to see the changes.

PHP: Interfaces and inheritance in a name spaced environment

I am trying to use a interface or child class to work in a situation where I am using class hints on a method argument and keep getting the following warning:
$print_r(class_parents($listing));
$propertyTable -> getPhotos($listing);
Array ( [Tools\Object\Property] => Tools\Object\Property )
Catchable fatal error: Argument 1 passed to Tools\Db\PhotoTable::getPhotos() must be an
instance of Tools\Db\Property, instance of Tools\Object\Listing given, called in ...
and defined in ...
This is strange as you can see when tested listing extends property (see below). Why would I get this error?
I have set up a very basic test case and have figured out that type hints should accept a child class or a class that implements the required class where that class is an interface. However, in a name spaced Zend Framework 2 environment I cannot get this to work.
My code for the various classes looks like this:
namespace Tools\Db;
class PhotoTable
{
public function getPhotos(Property $propertyObject )
{
//code goes here
}
}
namespace Tools\Object;
use Tools\Object\PhotoInterface as PhotoInterface;
class property //implements photoInterface
{
public function getUrl(){ code goes here}
public function getPhotos(){ code goes here}
}//end class
use Tools\Object\PhotoInterface as PhotoInterface;
class Listing extends Property implements PhotoInterface
{
//code goes here
}
namespace Tools\Object;
interface PhotoInterface
{
public function getUrl();
public function getPhotos();
}
I can get the code above to work if I copy this all into a single file and eliminate the namespaces. Basically:
if I require property in PhotoTable I can pass Listing as it extends property.
If I require PhotoInterface I can pass Listing as it implements this interface.
But I get this weird error when I have essentially the same classes in a different files in a name spaced Zend Framework 2 environment.
Is there an extra complication in a name spaced environment I need to take into account of or am I missing something really basic.
It appears that the issue involved the name-spaced files included in the head of the script. Specifically, it appears you need to include not only the class being am passed, but also the specified parent classes or any Interface classes if they are specified in the type hint.
To give an example if my class type hint suggests I need 'property' class, then if I am sending it the 'Listing' object, it seems I need to include property in the header like this:
namespace Tools\Object;
use Tools\Object\Property; //the parent class
use Tools\Object\Listing; //the child class
This eliminates the fatal error, but it seems strange that PHP cannot automatically determine the class automatically. I assume it is something to do with the complexities of a name spaced environment.

How do I extend the code igniter controller class?

In my CI system\libraries directory I have a new class named DD_Controller.php. This file looks like this:
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
class DD_Controller extends Controller
{
protected $ddauthentication;
function __construct()
{
parent::Controller();
$this->ddauthentication = "Authenticated";
}
}
?>
My application controller is defined like this:
class Inquiry extends DD_Controller
{...}
The Inquiry class works fine when I extend Controller, but I get a
Fatal error: Class 'DD_Controller' not
found in
C:\development\localhost\applications\inquiry\controllers\inquiry.php
on line 4
When I extend DD_Controller. In the config file I have the prefix defined as such:
$config['subclass_prefix'] = 'DD_';
Any idea of what I'm missing?
TIA
This is a better approach. Do the following:
Go to the following directory: your_ci_app/application/core/ and create a php file called MY_Controller.php (this file will be where your top parent classes will reside)
Open this the file you just created and add your multiple classes, like so:
class Admin_Parent extends CI_Controller {
public function __construct() {
parent::__construct();
}
public function test() {
var_dump("from Admin_Parent");
}
}
class User_Parent extends CI_Controller {
public function __construct() {
parent::__construct();
}
public function test(){
var_dump("from User_Parent");
}
}
Create your children controllers under this directory your_ci_app/application/controllers/ . I will call it adminchild.php
Open adminchild.php and create your controller code, make sure to extend the name of the parent class, like so:
class Adminchild extends Admin_Parent {
function __construct() {
parent::__construct();
}
function test() {
parent::test();
}
}
DD_Controller.php should be in /system/application/libraries/
If you're using the same CI for multiple apps, and you want them all to be able to extends their controllers to your custom one then you can extend the base Controller class in the same file.
In system/libraries/Controller.php below the Controller class:
class Mega_Controller extends Controller {
function Mega_Controller()
{
parent::Controller();
// anything you want to do in every controller, ye shall perform here.
}
}
Then you'll be able to do this in your app controllers:
class Home extends Mega_Controller {
....
Since the extended controller class you created will be available. I think this is better then overwriting the base controller, but that would work as well.
I recommend to avoid "cracking" CodeIgniter core files.
Better use its native extending possibilities and try to fit into them.
The same rule I would recommend for any PHP library / CMS.
This rule has few reasons:
- ability to quiclky upgrade without takint into account thousands of notes where and how was cracked in core files;
- portability;
- possibility to share your code - eg, this will be usable by both you and your friends in case of need, and it will help them to keep their library up to date, the same as you.
In other words, this is much more professional and it pays to you in the future by usability, portability and by update application possibility.
Regarding your personal question...
As for me, there is nothing bad to create your own library with everything you need to extend native CodeIgniter Controller, then load this library in Controller's constructor and you are done. The only thing to make better usability is to give short name to your library.
This way you can even divide what you need in different pieces and put into separate libraries:
WebFeatures
AdminFeatures
etc.
Then you just load needed libraries in your controller's constructor and you are done.
P.S. I know that proposed way does not fit into "right" OOP concept, but in the same time you must never forget about the integrity of the libraries used.
Everything above is just one more view of mine 7-years experience in professional web development, so I hope it will be helpful if not to follow, then at least to take into account.
Regards,
Anton

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