Joomla - How to override component controller? - joomla

I want to override a controller inside a component
ie;
File path : components/com_test/controllers/test.php
how to override test.php ?

As Pritesh mentioned, you can't*.
I can see a couple of ways to achieve the result:
You can create a new controller which extends your test.php controller, and invoke that instead; in order to achieve this, the controller must never use JPATH_COMPONENT and you'll have to override the view as well to point to the right component.
Add a special task to your view, and intercept it with a system plugin in OnAfterRoute(). You won't be touching the original controller, but your plugin will fire before the original controller, so it can take action, manipulate input and output, and eventually avoid invoking the original controller altogether.
--
if editing the original controller could seem like an option, please disregard it: the original component will be updated from time to time and you'd be entering a maintenance nightmare.
Very often I have to achieve just this result. And 90% of the time I achieve this in a system plugin. In case of improvements, I contribute the code back to the original developer, who usually integrates the features in their next release. Don't forget to let the original developers know, you'll help improve their products and save yourself time.
Actually you can override quite a large part of the core, by loading the class before Joomla does; this limits to non-core classes but it is feasible. That's what I was referring to in n.2

we can not override the controller and model in joomla we will override only views of the component.

Related

How to handle conditional rendering of views related to same controller's action?

I am developing a simple CRMish application. Let's say I can create tasks and clients. Both can be created independently, but they can also be created in a process. I have a views called create.blade.php for these two actions.
When you are creating a task for example, at some point you have a button choose a customer / create a customer which opens a modal dialog (so you can pick a customer and assign it to a task in one step :)). And here it starts to get muddy. I want my form part from create.blade.php to be rendered in modal dialog and to do so I need to fetch this hitting my create action, which normally returns full form that extends master.blade.php.
How would you handle this kind of design problem? For now it would be a little, innocent switch or if before return view() in my create action but I know that it will look like spaghetti carbonara at some point.
My ideas are as follows:
ifs/switch as long as it's readable and it's only about returning
different views (but you know it will include logic, different
variables etc. at some point..)
move ifs/switch logic to some request class and call return
view($request->getView()) so my controller will be a little bit
cleaner and follow SRP
create different classes for "ajax" requests, and "normal" requests.
same as above but because the logic of fetching some data used in
form etc. are common for both of the scenarios I can create a base
abstract class of TaskController and than extend this for "normal"
request and "ajax" request scenario. This is most advanced idea, but
I think i follow SRP as well as I remove code duplication cause
fetching common data will be placed in abstract class
Do you have any other ideas of how to handle this?
I have ended up with a little conditional in my create.blade.php view.
#extends((( Request::ajax()) ? 'layouts.modal' : 'layouts.master' ))
According to #Kristo I wont overengineer, and stick with this simple & readable solution.
UPDATE
I have created a little extension, as I decided that I will not load my modals via Ajax but simply inject them on compile time. Here is the code :)
https://github.com/3amprogrammer/modal-blade-extension

Implementing Front Controller pattern

I've been trying to implement a Front Controller on a VBScript (ASP Classic) based system for a couple of days. I come from a ASP.NET MVC and Java background, where MVC implementations are kind common and mostly done by existing frameworks. On VBScript, however, there's almost nothing done in this area, so it is the reason why I'm trying to do it by myself. I used this and this article as a guide on how to implement it.
I believed at first that I'd need to define some constant parameters for each request, so I created 3:
class_command 'which command responsible to execute the correct class handler
action 'which method of the class handler to execute
action_params 'which parameters the action will need
Next, I defined a generic controller handler for treating the request:
Public Function Controller_Handler(action_params)
Its task is to extract the constant parameters (class_command, action, action_params) and treat any errors (I'll add later a filter to process it) that might come like absence of the constant parameters or authentication problems.
But soon I realized a problem: how will the handler know which command to call, since the request is a string? I can't simply converting it to class using reflection, because VBScript (I think) doesn't have a reflection library or built-in feature.
So I thought I could create a Switch Case like this:
Select action_Params.Item("action_params")
Case "command_A"
' Call Command A
Case "command_B"
' Call Command_B
.
.
.
Case "Command_X"
' And so on
End Select
But that would kinda procedural way to do it. Next I thought of creating a XML file which would map all the commands and other stuff.
So my question is: is this a good way of implementing a Front Controlller pattern, considering VBScript limitations? If not, could you provide a guidance (hopefully with some example, even a simple one) on how can I do it?
Moving from classic to .net/mvc I can share what I did in classic asp to try to emulate this behavior as closely as possible without making it too much of a maintenance issue.
Using URL Rewrite in IIS are my routes. I usually just make one route and direct/rewrite all inbound requests to one controller.asp page to simplify things and not have a bunch of rules and controller redirects directly in my URL Rewrite settings for maintaining it easier (for me).
Using Request.ServerVariables("HTTP_X-ORIGINAL-URL") in controllers.asp you can grab the actual URL that was entered, which return something like.. /real/url
In controllers.asp programatically call the view based on the entered url using Server.Execute("view1.asp")
I have one class file called routes.asp that is included in each model/class file, and helps me gather the URL properties oRoute.GetPath_FirstDirectory() and so on. The model/class file then uses this data to create its property values that can be consumed by the view. Using CLASS_INITIALIZE in each model/class to populate itself from the route/url, or it could also be done directly in the view.
In the respective view I include my class/model file (if even needed) using <!--#include file="class.asp"--> then simply open Set Model = new cModelClass to initialize and start using it in the view. I don't include the class in the controllers.asp because the view will not inherit any of the variables from controllers.asp when using Server.Execute() to the view. So I include it directly in the view.
Error handling can be at multiple levels here, but ideally its in the controllers.asp. Specific error handling is usually at the actual model/class CLASS_INITIALIZE to avoid redundant use of the class in the controller, since it's already going to be initialized in the view.
Now this is not exactly what goes in in .Net mvc, but it's the best way I've come up with, and easiest to maintain for me. Maybe others have other implementations, but this is mine and solely based on my experience. And so far, it's been working out pretty well.

Which is better in codeigniter? Adding a function in a helper or adding a function in an extended base class

In a codeigniter project i have to do some set of stuff in one than one controller.
I code all that stuff in a function and now i need to call whenever necessary.
i think Writing this function in more than one controller is not good.
i have 2 options,
create a helper and write these function in that and include the helper in necessary controllers.
Since i have extended CI base controller (My_Controller) and most of my controllers are extended that controller, i can write this function to my base controller also.
I have confused which one is better, right way?
Which one will speed up the process?
Is the second way slows the site?
They are identical for all intents and purposes.
Using a helper allows you to make the code portable, so you can use it in other projects, or to be called from anywhere in the code base, in the case of a formatting function for example
If you were planning to put it in a controller, then MY_Controller is best bet
Just to help you on you endeavor what i do is: (this is just me)
If i need to use something in the views, i use a helper a custom one or built in.
If i want to do something on a controller that other controller will be using too and don't want it to mess up or crowd my controller i use a library (pretty much you can use a helper but i chose to use a library)
If i want to load lets say a method, to affect Globally or some of the controller i use the base controller. (you could also use helper or library)
The key is you are not restricted to one, choose the best that suits you, as the saying goes, there are many ways to skin a cat, but please don't skin a cat..

Codeigniter Inter Controller Communication

I am new to MVC, CodeIginter. Instead of getting things easy, it needs lot of code to be written for a simple application. These are might be happening becouse I am new. So I have few confusions about this thing. Any kind of help is appreciated.
1) Methods are written in one controller can not be accessed in another controller classes. I have to write a new function for the same functionality.
2) To create website administration panel (back-end) in none mvc panel, we usually create it in a new folder. Is this thing possible in CodeIgniter? If not what about the admin (back-end)??
Let's try to clear some of your doubts about this.
1) Calling a controller's method from another controller is not possible, and it's whtouth meaning by the way.
A controller is supposed to get an action from the URL (which is routed by CI to the right controller for the task) and, based on that, decide which Model and which model's method needs be called to elaborate the data requested.
The model, then, hands back the result of this elaboration to the controller, which , in turns, decides to which view pass this results.
The view, eventually, is structured to get those datas and display them.
SO, as you can see, calling a controllers' method from another controller is nonsense, it would be like going to a page and finding another one instead; if you want to pass to another controller the request...well, there's the redirect for that.
If you find out you have the same functionalities in several moment, think twice:
What is a funcionality? Do you mean somehtin like "display posts" in controller "archive" and "display posts" in controller "news" ? they're hardly the same functionality; they can maybe share views, or models, but that's it.
For functions that doesn't relate to URLs, but involve some further elaboration (which might be wrong to do in Models) and are nonetheless called in a controller, you have library instead. Think at the "form_validation" library, which is called in a controller's method, but has its own peculiar (and encapsulated) functionalies. Ora a "session" library, or an "authentication" library
2) To create an admin panel the easiest thing is: create an "admin" controller (which is accesible then to www.mysite.com/index.php/admin), and put all the administration actions there, in its methods: create_page(), edit_page(), manage_users(), whatever.
In order to avoid people accessing it freely you need to build an authentication system, which, in its simplest and barabone strucutre, might be a check of wheter a session is set or not (maybe a check done at __construct() time).
But you can find nice Auth libraries out there already made, such as Ion Auth or Tank Auth (the 2 most popular to my knowledge)
Hope things are a bit clearer now. See also Interstellar_Coder's comment at this answer if you're interested in the modular HMVC approach.
1) Methods are written in one controller can not be accessed in another controller classes. I have to write a new function for the same functionality.
What's the functionality about? Perhaps you should write a library/helper instead, controller's logic should be limited to request flow or something else but not too complicated. For that, put the functionality in the model, or if more general, in library/helper.
2) To create website administration panel (back-end) in none mvc panel, we usually create it in a new folder. Is this thing possible in CodeIgniter? If not what about the admin (back-end)??
I don't get it, could you elaborate more?

Codeigniter Dynamically load controller depending on url (outside routes.php)

using CodeIgniter normally one has to specify the controllers in the config/routes.php file.
This is not to handy, so I would like to be able to do something like this in a controller.
get url parts and check if the first part is specified in an array
if so, load the specified controller, if not, load default controller.
It basically mimics the behavior of the routes file, but there is no need to specify the wildcards before. I am using a base controller I extend with every controller, but I would like to have this controller just load (or include) the needed controller.
Does anyone have any idea how I can do this in a good way?
Thanks in advance.
// Edit
Okay, so here is my scenario.
I have cms and users can choose to include modules (e.g. a gallery).
I need to inlcude all the gallery php scripts without having to have "gallery" in the url.
I figured it would work if I use a "main controller" which loads another controller depending on the modules chosen. I realize this might not be the best way, so if there is a "clean" way to do it, please tell me.
As far as I know models are just for database stuff, so putting a whole gallery in there is not right either. The Plugin itself will of course be a library, but there is going to be some code to load the libs depending on the demands, get the database data, etc.
Thanks
The way you're doing this is incorrect. You never should take over the routing function to do this. What you need is to use some kind of module functionality to include the required methods and models; a module doesn't require to have route-accessible methods, so it's basically a "library" with a model and views.
If I remember correctly there are several plugins that provide this, One was HMVC (google it).
The ideal form would be to load the "Module" on demand from your controller, like you do with the core CodeIgniter Libraries; so lets say you're inside the blog controller action and you want to include the comment module which is used on gallery and on images, you just include the module and call it's methods to get the data which you can then pass to the view as needed; you can even render partials and store them into a variable to pass to your master controller.
Hope this is enough to get you on the right track :)
I may be misunderstanding your question but you want to load your controllers if you go to them and if not you want to go to your default.
If I am understanding correctly you can do a couple things in your routes have a route that takes everything to your default controller.
In your controller have an array of all your controllers then implode the array to a regular expression
$array = [c1, c2, c3, c4];
$str = implode('|', $array);
$regex = "($str)"
now just add your regex to a route
now redirect as you see fit.
But this is really what the routes file is for you you are just dancing around something that should be used.

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