What are the best practices for handling errors and exceptions in Yii routing?

2 Use error handler

Another important component for handling errors and exceptions in Yii routing is the error handler. The error handler is a service that intercepts any uncaught PHP errors or exceptions, and converts them into appropriate HTTP responses. The error handler also renders the error views, which are the pages that show the error messages to the users. Yii provides two default error views: one for debug mode, which shows the detailed information, and one for production mode, which shows a generic message. You can customize the error views by modifying the files in the @yii/views directory, or by specifying your own view files in the error handler configuration. You can also change the error handler behavior by overriding its methods or properties, such as errorAction, errorView, exceptionView, or handleError.

3 Use custom rules

Sometimes, you may want to handle errors and exceptions in Yii routing in a more specific or customized way, depending on the type of error, the request method, the user role, or other criteria. For example, you may want to redirect the user to a different page, show a custom message, or perform some additional logic. In this case, you can use custom rules to define how your application should respond to different errors and exceptions. Custom rules are classes that implement the yii\web\ErrorActionInterface interface, which defines a single method: run(). The run() method receives the exception as a parameter, and returns a response object. You can then register your custom rules in the error handler configuration, by mapping the exception class name to the rule class name. For example, if you want to handle NotFoundHttpException with a custom rule, you can write something like this in your web.php file:

'components' => [
    'errorHandler' => [
        'errorAction' => [
            'yii\web\NotFoundHttpException' => 'app\components\MyNotFoundRule',
        ],
    ],
],        

4 Use aliases

Another best practice for handling errors and exceptions in Yii routing is to use aliases for your URLs. Aliases are short and readable names that represent longer and complex URLs, and they can be defined globally or locally in your application. Aliases can help you avoid hard-coding URLs in your code, which can make your application more maintainable and flexible. Aliases can also help you handle errors and exceptions in Yii routing more easily, by allowing you to change the URL without affecting the code logic. For example, if you want to change the URL of your error page from /site/error to /error, you can simply define an alias for it in your web.php file:

'aliases' => [
    '@error' => '/site/error',
],        

Then, you can use the alias wherever you need to refer to the error page, such as in your error handler configuration, your custom rules, or your redirection logic. For example:

'components' => [
    'errorHandler' => [
        'errorView' => '@error',
    ],
],        

5 Use logging

The last best practice for handling errors and exceptions in Yii routing is to use logging. Logging is a process of recording and storing information about your application's activities, events, and errors, which can help you monitor, analyze, and debug your application. Yii provides a powerful and flexible logging system, which consists of three main components: log targets, log messages, and log levels. Log targets are the destinations where the log messages are sent, such as files, databases, emails, or consoles. Log messages are the pieces of information that are logged, such as timestamps, categories, texts, or contexts. Log levels are the severity levels of the log messages, such as error, warning, info, or trace. You can configure your logging system in your web.php file, by specifying the log component and its targets, messages, and levels. For example:

'components' => [
    'log' => [
        'targets' => [
            [
                'class' => 'yii\log\FileTarget',
                'levels' => ['error', 'warning'],
                'logFile' => '@runtime/logs/app.log',
            ],
        ],
    ],
],        

This configuration will log all errors and warnings to a file named app.log in the runtime directory. You can also use the Yii::error(), Yii::warning(), Yii::info(), and Yii::trace() methods to create your own log messages in your code.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?