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 > 1.
Uncaught exceptions
When debug < 1 a CakeException will render 404 or 500 errors. If an uncaught exception is thrown and it is a type that ErrorHandler 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
exceptionRendereroption 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:
$options['errorLevel'] = E_ALL & ~E_NOTICE;Would enable handling for all non Notice errors.
See: ExceptionRenderer for more information on how to customize exception rendering.
Property Summary
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$_options protected
arrayOptions to use for the Error handling.
Method Summary
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__construct() public
Constructor
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_clearOutput() protected
Clear output buffers so error pages display properly.
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_displayError() protected
Display an error.
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_displayException() protected
Displays an exception response body.
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_getMessage() protected
Generates a formatted error message
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_logError() protected
Log an error.
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_logException() protected
Handles exception logging
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_sendResponse() protected
Method that can be easily stubbed in testing.
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_stop() protected
Stop the process.
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handleError() public
Set as the default error handler by CakePHP.
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handleException() public
Handle uncaught exceptions.
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handleFatalError() public
Display/Log a fatal error.
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mapErrorCode() public static
Map an error code into an Error word, and log location.
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register() public
Register the error and exception handlers.
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wrapAndHandleException() public
Checks the passed exception type. If it is an instance of
Errorthen, it wraps the passed object inside another Exception object for backwards compatibility purposes.
Method Detail
__construct() ¶ public
__construct(array $options = [])Constructor
Parameters
-
array$options optional The options for error handling.
_clearOutput() ¶ protected
_clearOutput(): voidClear output buffers so error pages display properly.
Easily stubbed in testing.
Returns
void_displayError() ¶ protected
_displayError(array $error, bool $debug): voidDisplay an error.
Template method of BaseErrorHandler.
Only when debug > 2 will a formatted error be displayed.
Parameters
-
array$error An array of error data.
-
bool$debug Whether or not the app is in debug mode.
Returns
void_displayException() ¶ protected
_displayException(Exception $exception): voidDisplays an exception response body.
Subclasses should implement this method to display an uncaught exception as desired for the runtime they operate in.
Parameters
-
Exception$exception The exception to display
Returns
voidThrows
ExceptionWhen the chosen exception renderer is invalid.
_getMessage() ¶ protected
_getMessage(Exception $exception): stringGenerates a formatted error message
Parameters
-
Exception$exception Exception instance
Returns
string_logError() ¶ protected
_logError(string $level, array $data): boolLog an error.
Parameters
-
string$level The level name of the log.
-
array$data Array of error data.
Returns
bool_logException() ¶ protected
_logException(Exception $exception): boolHandles exception logging
Parameters
-
Exception$exception Exception instance.
Returns
bool_sendResponse() ¶ protected
_sendResponse(string|Cake\Network\Response $response): voidMethod that can be easily stubbed in testing.
Parameters
-
string|Cake\Network\Response$response Either the message or response object.
Returns
void_stop() ¶ protected
_stop(int $code): voidStop the process.
Implemented in subclasses that need it.
Parameters
-
int$code Exit code.
Returns
voidhandleError() ¶ public
handleError(int $code, string $description, string|null $file = null, int|null $line = null, array|null $context = null): boolSet as the default error handler by CakePHP.
Use config/error.php to customize or replace this error handler. This function will use Debugger to display errors when debug > 0. And will log errors to Log, when debug == 0.
You can use the 'errorLevel' option to set what type of errors will be handled. Stack traces for errors can be enabled with the 'trace' option.
Parameters
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int$code Code of error
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string$description Error description
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string|null$file optional File on which error occurred
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int|null$line optional Line that triggered the error
-
array|null$context optional Context
Returns
boolhandleException() ¶ public
handleException(Exception $exception): voidHandle uncaught exceptions.
Uses a template method provided by subclasses to display errors in an environment appropriate way.
Parameters
-
Exception$exception Exception instance.
Returns
voidThrows
ExceptionWhen renderer class not found
See Also
handleFatalError() ¶ public
handleFatalError(int $code, string $description, string $file, int $line): boolDisplay/Log a fatal error.
Parameters
-
int$code Code of error
-
string$description Error description
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string$file File on which error occurred
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int$line Line that triggered the error
Returns
boolmapErrorCode() ¶ public static
mapErrorCode(int $code): arrayMap an error code into an Error word, and log location.
Parameters
-
int$code Error code to map
Returns
arraywrapAndHandleException() ¶ public
wrapAndHandleException(Exception|Error $exception): voidChecks the passed exception type. If it is an instance of Error
then, it wraps the passed object inside another Exception object
for backwards compatibility purposes.
Parameters
-
Exception|Error$exception The exception to handle
Returns
void