Class ErrorHandler

Error Handler provides basic error and exception handling for your application. It captures and handles all unhandled exceptions and errors. Displays helpful framework errors when debug mode is on.

Uncaught exceptions

When debug mode is off a ExceptionRenderer will render 404 or 500 errors. If an uncaught exception is thrown and it is a type that ExceptionRenderer does not know about it will be treated as a 500 error.

Implementing application specific exception handling

You can implement application specific exception handling in one of a few ways. Each approach gives you different amounts of control over the exception handling process.

• Modify config/error.php and setup custom exception handling.
• Use the exceptionRenderer option to inject an Exception renderer. This will let you keep the existing handling logic but override the rendering logic.

Create your own Exception handler

This gives you full control over the exception handling process. The class you choose should be loaded in your config/error.php and registered as the default exception handler.

Using a custom renderer with exceptionRenderer

If you don't want to take control of the exception handling, but want to change how exceptions are rendered you can use exceptionRenderer option to choose a class to render exception pages. By default Cake\Error\ExceptionRenderer is used. Your custom exception renderer class should be placed in src/Error.

Your custom renderer should expect an exception in its constructor, and implement a render method. Failing to do so will cause additional errors.

Logging exceptions

Using the built-in exception handling, you can log all the exceptions that are dealt with by ErrorHandler by setting log option to true in your config/error.php. Enabling this will log every exception to Log and the configured loggers.

PHP errors

Error handler also provides the built in features for handling php errors (trigger_error). While in debug mode, errors will be output to the screen using debugger. While in production mode, errors will be logged to Log. You can control which errors are logged by setting errorLevel option in config/error.php.

Logging errors

When ErrorHandler is used for handling errors, you can enable error logging by setting the log option to true. This will log all errors to the configured log handlers.

Controlling what errors are logged/displayed

You can control which errors are logged / displayed by ErrorHandler by setting errorLevel. Setting this to one or a combination of a few of the E_* constants will only enable the specified errors:

$options['errorLevel'] = E_ALL & ~E_NOTICE;

Would enable handling for all non Notice errors.