Alternative to using codeigniter libraries for additional classes - codeigniter

I have an existing controller (classA) which needs to use a new helper class (classB). Typically I would place classB into a library and do
$this->load->library('classb');
$this->classb->method();
However, I've run into a problem where I am defining const's in my classB which are required by the constructor
classB {
const MYDEFINE = 1;
...
}
The problem with this approach is the definition of MYDEFINE is NOT available until I load the library, but I need to create the $params array with the arguments to send the classB constructor. So I get a case of chicken vs. egg
$params = array();
$params['open_mode'] = classB::MYDEFINE;
$instance = $this->load->library('classB', $params);
I've been able to solve this problem by not using a library - and instead using a #include_once('classB') in my classA controller which is working fine. The file classB.php is therefore stored in the controllers directory.
I'm wondering if others have run across this problem and how they might have solved it (other than by decaaring the consts elsewhere). I looked at a post by PhilSurgeon (http://philsturgeon.co.uk/blog/2010/02/CodeIgniter-Base-Classes-Keeping-it-DRY) on an alternative method but its not quite the right fit for this problem (at least I don't think so).

I'm unclear why you would declare a constant, and then load it into the config when you initialize the class...that makes no sense, is why you have the chicken-and-egg issue
I would set things up roughly as:
private $myvar = 'My Constant Value';
function __construct() ... etc
and then you can access it using:
$this->myvar
anywhere in your library class, including the construct if you want to change it via your config
EDIT: You could still use a constant is that is more appropriate, but then pass it to the $this->myvar in your construct() as a above. The point is, your Constant should never be worked with outside of the class

how about creating a bootstrap library
like
include 'path/to/class/b';
class Init_class_b Extends class_b
{
function __construct($params)
{
// handle the variables here
parent::__construct();
}
}
then:
$this->load->library('Init_class_b',$params_for_construct);
$this->Init_class_b->method()

Related

In CakePHP 3, how can I use the UrlHelper in a Shell to generate an URL?

To use Emails, I just
use Cake\Network\Email\Email;
$email = new Email();
but trying that with UrlHelper is unsuccessful.
As unsuccessful is with a
$url_helper = new UrlHelper;
because it gives me
Argument 1 passed to Cake\View\Helper::__construct() must be an instance of Cake\View\View.
But I don't have View in Shell, I suppose.
Thanks.
Using a helper in the shell is not the right way to approach this. The helper as well is just wrapping the Router. So instead use the Router directly:
use Cake\Routing\Router;
$url = Router::url([/*...*/], true);
Also note that you can change the base URL as needed by calling Router::fullBaseUrl(), it's a getter and setter. See the documentation.
This is better because:
It's introducing less dependencies
Less tight coupling (OK, you get a singleton instead...)
Doesn't violate MVC
Smaller footprint
You could probably follow a similar method for mocking out a helper in the shell as they do for mocking out a helper for unit testing. Try:
<?php
use Cake\View\View;
use Cake\View\Helper\UrlHelper;
class FooShell extends Shell
{
public $url_helper = null;
public function bar()
{
$view = new View();
$this->url_helper = new UrlHelper($view);
// URL Helper functionality created here
}
}
Here is the docs I used for mocking out a helper in CakePHP 3.

Laravel core method confusion

I have been digging in the core of Laravel because I would like to understand how it works. But I come up with a method that I just cannot wrap my head around even after 3 days.
In start.php the app is binded to itself. So far so good. But when I check the $app->share method I am lost.
public function share(Closure $closure)
{
return function($container) use ($closure)
{
// We'll simply declare a static variable within the Closures and if
// it has not been set we'll execute the given Closure to resolve
// the value and return it back to the consumers of the method.
static $object;
if (is_null($object))
{
$object = $closure($container);
}
return $object;
};
}
This method returns an anonymous function which when executed returns an instance of the app. Do I see that right? Why is this? Why do you want to return a closure and not just the instance. This seems like a strange way, but I am quite sure that there is a reason ;) ??
UPDATE
The line in start.php:
$app['app'] = $app->share(function($app) { return $app; });
So I would think that $app['app'] is a closure object. However if I do get_class the class is Illuminate\Foundation\Application .
Furthermore there is also no way to execute it as $app'app' will not work obviously.
$app is no normal array, it is actually an instance of Illuminate\Foundation\Application1, an extension of Illuminate\Container\Container2, which implements ArrayAccess. But you know this already, as that's where the share() method lives.
The container binds keys to closures, when the keys are accessed the value is fetched from memory or, on first access, the bound closure is called and the resulting value is returned. When a key is set on the container it is wrapped in a closure unless it is already a closure.
This provides a consistent internal interface for the container, so that the code is not constantly type checking its contents. It will also only load the references you actually use are into memory - it is thought that the footprint of a closure is lighter than that of a fully loaded class instance. But once loaded, you get the benefit of working with the same instance for the rest of the request.
Why the app is not registered on the container using instance() I don't know though - perhaps it produces recursive references in trace and dump output.

Something that escapes me about Symfony's controllers

Take a look to that code
<?php
namespace Sestante\SestanteBundle\Controller;
use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\Request;
use Sestante\SestanteBundle\Model\StrutturaManager;
class MainController extends Controller
{
public function indexAction(Request $request)
{
return $this->render('SestanteSestanteBundle:Main:index.html.twig');
}
public function showLodgingsAction(Request $request)
{
$repo = $this->getDoctrine()->getRepository('SestanteSestanteBundle:Struttura');
$usr = $this->get('security.context')->getToken()->getUser();
$usrId = $usr->getId();
$sm = new StrutturaManager($repo);
$lodgingList = $sm->retrieveLodgingsFromUser($usrId);
return $this->render('SestanteSestanteBundle:Main:showLodgings.html.twig',array('lodgingList' => $lodgingList));
}
}
This is a controller for an application that I've been writing.
Take a look to showLodgingsAction. I've tryied to place all business logic into a model (StrutturaManager) that with a repository (that I've passed directly from controller because, as far I know, they're available only here or via D.I.) query my db, do some elaboration and return a list that I'll render onto a template.
First question: Is this "code separation" good, or exists a better way for do what I'm trying to do?
Second question: suppose that, now, I want to use an object of StrutturaManager type into indexAction. Remember that mine object want a repository. So, have I to declare again, and again, and again, all my object for every controller's action where I want to use them? I suppose that must exist a smarter method but, at the moment, I don't understand which.
Define StrutturaManager as a service and inject the EntityManager into it. This way the manager will have access to repositories you need and controllers won't know about Doctrine nor repositories — which is a good practice.

Codeigniter models loaded in controller overwritten by models loaded in models

I'm having Codeigniter object scope confusion.
Say I load a model in a controller:
$this->load->model('A');
$this->A->loadUser(123); // loads user with ID 123
// output of $this->A now shows user 123
$this->load->model('B');
$this->B->examineUser ();
// output of $this->A now shows user 345
class B extends Model
{
public function examineUser ()
{
$this->load->model('A');
$this->A->loadUser(345); // loads user with ID 345
}
}
I would have thought that $this->A would be different from $this->B->A but they are not. What is the best solution to this issue? It appears the ->load->model('A') in the examineUser () method does nothing because it was loaded in the controller. Then the call to loadUser () inside that method overwrites the stored properties of $this->A. This seems like a bugfest waiting to happen. If I needed global models, I would have use static classes. What I wanted was something scoped pretty much locally to the model object I was in.
Is there a way I can accomplish this but not go way outside of CI's normal way of operating?
Followup/related:
Where do most people put there "->load->model" calls? All at the beginning of a controller action? I figured it would be easier -- though perhaps not excellent programming from a dependency injection perspective -- to load them in the model itself (construct or each method).
Whenever you use the Loader Class ($this->load->), it will load the object into the main CI object. The CI object is the one you keep referring to as $this->. What you've done is load model A twice into the CI object.
Essentially, all object loaded using the Loader class goes into a single global scope. If you need two of the same type, give them different names, as per $this->load->model('A','C'). I don't know of any way around it unless you revert to using bog-standard PHP.
In my team's code, we generally load the models in the controller's constructor, then load the data to send to the view in the function, often _remap().
This is not how the loader works sadly. CodeIgniter implements a singleton pattern, which will check to see if the class is included, instantiated and set to $this->A then will be ignored if loaded again. Even if you are inside a model, $this->A will be referenced to the super-instance via the __get() in class Model. Alis it, or just do:
class B extends Model
{
public function examineUser ()
{
$user = new A;
$user->loadUser(345); // loads user with ID 345
}
}
Here's what I've decided to do, please comment if you have advice:
I've extended the CI Loader class:
<?php
class SSR_Loader extends CI_Loader
{
function __construct()
{
parent::__construct ();
}
/**
* Model Retriever
*
* Written by handerson#executiveboard.com to create and return a model instead of putting it into global $this
*
* Based on original 2.0.2 CI_Loader::model ()
*
*/
function get_model($model)
{
if (empty ($model))
{
return;
}
$name = basename ($model);
if (!in_array($name, $this->_ci_models, TRUE))
{
$this->model ($model);
}
$name = ucfirst($name);
return new $name ();
}
}
Do any CI guru's see a problem with that before I invest time in changing my code a bit to accept the return obj, ala:
// in a controller:
public function test ($user_id=null)
{
$this->_logged_in_user = $this->load->get_model ('/db/users');
$this->_viewed_user = $this->load->get_model ('/db/users');
$this->_logged_in_user->load($this->session->userdata ('user.id'));
$this->_viewed_user->load($user_id);
}
I could also do private $_logged_in_user to make it available in the controller but positively force it to be limited to just the current controller and not spill anywhere else, or I could just do $_logged_in_user = $this->load->get_model ('/db/users'); and limit it to just the current method, which is probably what I'll do more often.
This seems like a pretty straightforward way to "fix" this issue (I say "fix" b/c it's not really a bug, just a way of doing things that I think is a bad idea). Anyone see any flaws?

Global Variables in CodeIgniter not Working

I want to generate global variables in CodeIgniter by creating my own library and config file. This is what I wrote ini my library file, let's say globalvars.php. I put it in /application/libraries.
class Globalvars{
function __construct($config = array())
{
foreach ($config as $key => $value) {
$data[$key] = $value;
}
$CI =& get_instance();
$CI->load->library('session');
$CI->load->vars($data);
}
}
I want the user id stored in the session to be available in global variable, so I wrote this in my config file. It's named also globalvars.php. It's in /application/config directory.
$config['user']=$this->session->userdata('id');
I then test to see if it's working by write it in my controller this way.
echo $data['user'];
But I get this error in the browser
Message: Undefined property: CI_Loader::$session
Filename: config/globalvars.php
It seems that the session functions is not defined yet. How can I get it work? What have I missed here? Any help would be appreciated.
You cannot use the session library in config file.
The config files are loaded before any libraries, so $this->session is undefined.
The config.php has to be loaded in order for the Session class to even be initialized, as it reads settings from that file.
A lot of issues with this type of thing (setting some "global" data) can be resolved using a base controller, and extending it in your controllers.
// core/MY_Controller.php
MY_Controller extends CI_Controller {
function __construct()
{
parent::__construct(); // Now the Session class should be loaded
// set config items here
}
}
"Normal" controllers will now extend MY_Controller to take advantage of this.
See: http://codeigniter.com/user_guide/general/core_classes.html for more details.
In addition, when you load->vars(), they are available to the view layer only, it does not create a global variable called $data as you seem to be trying to access. If you do this:
$this->load->vars(array('user' => '1'));
You would access it in a file loaded by $this->load->view() like this:
echo $user; // outputs "1"
See: http://codeigniter.com/user_guide/libraries/loader.html
$this->load->vars($array)
This function takes an associative array as input and generates
variables using the PHP extract function. This function produces the
same result as using the second parameter of the $this->load->view()
function above. The reason you might want to use this function
independently is if you would like to set some global variables in the
constructor of your controller and have them become available in any
view file loaded from any function. You can have multiple calls to
this function. The data get cached and merged into one array for
conversion to variables.
I will say that as an experienced Codeigniter user, the concept of a "global vars" class is a bit wonky and probably unnecessary, especially when it's already so easy to get and set config items. You could definitely run into some confusing issues and variable name conflicts with this method (pre-loading lots of view variables on every request).

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