PHP MVC 404/Error Handling for bad URLS - php

Question

I am trying to build a custom MVC framework in PHP. I'm just starting out with this MVC and framework stuff and I'm not very good.
I created all the general stuff. The library for the model, controller and view and I got a general app up and running.
I would like to now incorporate some error handling. Primarily on the user side for bad urls. I want to make Page Not Found or 404 Errors. So i need a way to check for bad controllers,actions and query strings. And then send the users to a 404 page.
What is the best practice for doing this in an MVC environment?
EDIT
This is a learning based project it is not for production.

Answer 1

First of all it is not recommended to develop a custom framework your own if you are planning it for production. There are many great frameworks that you can make use of, with good flexibility and more importantly with more performance.
Coming to the problem. First write a custom exception handler for managing 404. I recommend to call them in your system/core class where you create Object of the controller and invoke the action, if they dont exists.

Answer 2

Add an error handler in your bootstrap.
For example, in mine I have:
public function error(){
$this->view->msg = 'Page not found';
$this->view->render('error/index');
}
Add a check for the method in the bootstrap. Where depends on your structure. If the method or controller isn't found call the error() method.
Thats probably the simplest way.

Answer 3

you can use .htaccess (if using apache) to route all request to your index page. Usually the the controller (and action), view is associated with a file or function. so, if you want to show custom error message, just check for the file, class, or its methods.
for example:- index.php?controller=control1&action=action1.
if(!file_exists('control1.php'))
if(!method_exists($controller, 'action1'))
//route to error handler

Answer 4

Well, if you are learning like you said, you shouldn't use your framework for production code because one thing is breaking the app at home and another one is loosing money with angry clients :)
Back to the problem. I've built my own custom framework for PHP applications and I have in my framework several Routers. The idea is that each Router handles a specific pattern of Route, like this:
http://someapplication.org/services/awebservice/
This code would call the ServiceRouter, which handles Routing web services. Before calling any Router I check if the Router exists, and if it does, then I would call a method to check if the route is valid, something like this:
if ( RoutingManager::RouterExists($route) )
{
$router = RoutingManager::GetRouter($route);
if ( !$router->IsValid )
RoutingManager::RedirectTo404();
}
The idea is to locate your 404 handler to a class, and delegate the task of routing into different classes to allow a variety of Routers and make your application more changeable (scalable)
Hope I can help!