Handling Errors in Zend Framework

Quite a few times, applications using Zend framework might experience errors. Such errors can result in failure of the system, and hence, need to be handled effectively.

Usually, errors in the zend framework developments are handled using the error controller, but there are distinct ways to provide the execution to it.
In this post, we will look at some ways to boost the error controller and how to use it to handle different error conditions.

Structure of Error Controller

Let’s first have a look at the basics of the error controller. To enable the error controller, you have to set throw Exceptions to false in the controller.

Structuring the Error Controller

The simplest way to do is to just handle everything in the errorAction method. But if you separate different types of errors into separate actions, then it will be convenient to understand the controller. You can even define codes for a specific error without using the errorAction method. Additionally, it allows us to render error-specific view scripts conveniently.

Stimulating the Error Controller

A commonly used approach to stimulate the error controller is to just forward the request to it in an erroneous situation. Though this approach might sound simple, there is a small flaw to it. The flaw is that forwarding code is essentially generating a coupling between the error controller and this controller.
But if you think that you can make your code conveniently re-usable, then it is not possible. By forwarding to a particular action, you need anyone who wishes to use the code to execute an error controller with particular actions your code needs.
A better solution, in this case, would be to use exceptions. Hence, rather than forwarding, you need to throw an exception.
You need to throw a custom exception known as ParameterNotFoundException. While performing this action, it is possible to enable the usual error handling code of the framework to take over, and hence, the error is determined, and the error is passed on to the error controller.
Now, you can add a few codes in the error controller to handle such exceptions. Alternatively, if your project does not require custom handling for such an exception, you can use the generic handling code to solve the error.
This workflow is the same throughout the Zend-expressive. But there can be situations when it is just not enough.
So, let’s discuss the exceptions and how you can handle them.

Templated Errors

You would want to offer error messages in your site template. For this, we offer class similar to the FinalHandler, but this accepts a Zend/Expressive/Template/TemplateRendererInterface situation, and template names to employ for 404 and generic error situations. This makes it an excellent choice for use in production.
For this, you have to choose a templating system and make sure you have the needed dependencies installed. Next, you can establish the template error handler.

Whoops

This is a library for offering a more usable UI around exceptions as well as PHP errors. We offer integration within the library through Zend/Express/WhoopsErrorHandler. Such an error occurs from the TemplatedErrorHandler and uses features for non-exception errors and 404 status.
For this, you first have to install Whoops, and then you need to offer the error handlers a whoops runtime situation. Optionally, you can also offer template names.
You can add more numbers of handlers if needed.
As soon as you identify an exception, Zend-expressive adds some relevant data to the output from Whoops, mainly around the request information (HTTP request method, URI, route match attributes, and more).

Summing Up

It is not much about handling errors in Zend Framework. It is because there are ready to use components available that make it truly very easy. You just have to throw an exception, and define code in the error controller to handle it. As an important rule, you must at least record the exceptions that are out of reach of the error controller.