Error handling file to log all PHP errors to Graylog2

gistfile1.php

<?php
/**
 * This file sets up exception and error handlers to log errors to our Graylog2
 * server.
 *
 * @author Jeremy Cook
 */

//Add the autoloader generated by composer for dependencies.
require_once 'path/to/composer/autoload.php';

/**
 * Create a closure to handle uncaught exceptions
 */
set_exception_handler($handler = function(Exception $e) use (&$handler) {
    $message = sprintf(
        'Uncaught exception of type %s thrown in file %s at line %s%s.',
        get_class($e),
        $e->getFile(),
        $e->getLine(),
        $e->getMessage() ? sprintf(' with message "%s"', $e->getMessage()) : ''
    );
    LoggingHelper::getLogger()->addError($message, array(
        'Exception file'  => $e->getFile(),
        'Exception line'  => $e->getLine(),
        'Exception trace' => $e->getTraceAsString()
    ));
    /**
     * If there was a previous nested exception call this function recursively
     * to log that too.
     */
    if ($prev = $e->getPrevious()) {
        $handler($prev);
    }
});

/**
 * Set a custom error handler to make sure that errors are logged to Graylog.
 * Allows any non-fatal errors to be logged to the Graylog2 server.
 */
set_error_handler(function($errno, $errstr, $errfile, $errline, array $errcontext){
	$message = 'Error of level ';
	switch ($errno) {
		case E_USER_ERROR:
			$message .= 'E_USER_ERROR';
			break;
		case E_USER_WARNING:
			$message .= 'E_USER_WARNING';
			break;
		case E_USER_NOTICE:
			$message .= 'E_USER_NOTICE';
			break;
		case E_STRICT:
			$message .= 'E_STRICT';
			break;
		case E_RECOVERABLE_ERROR:
			$message .= 'E_RECOVERABLE_ERROR';
			break;
		case E_DEPRECATED:
			$message .= 'E_DEPRECATED';
			break;
		case E_USER_DEPRECATED:
			$message .= 'E_USER_DEPRECATED';
			break;
		case E_NOTICE:
			$message .= 'E_NOTICE';
			break;
		case E_WARNING:
			$message .= 'E_WARNING';
			break;
		default:
			$message .= sprintf('Unknown error level, code of %d passed', $errno);
	}
	$message .= sprintf(
		'. Error message was "%s" in file %s at line %d.',
		$errstr,
		$errfile,
		$errline
	);
	LoggingHelper::getLogger()->addError($message, $errcontext);

	return false;//Returning false will mean that PHP's error handling mechanism will not be bypassed.
});

/**
 * This function will be called before the script exits.
 * This allows us to catch and log any fatal errors in the Graylog2 server.
 * This is needed as the set_error_handler function cannot be used to handle
 * any of the errors in the array below.
 */
register_shutdown_function(function(){
    $codes = array(
        1   => 'E_ERROR',
        4   => 'E_PARSE',
        16  => 'E_CORE_ERROR',
        32  => 'E_CORE_WARNING',
        64  => 'E_COMPILE_ERROR',
        128 => 'E_COMPILE_WARNING'
    );
    $error = error_get_last();
    if (is_array($error) && array_key_exists($error['type'], $codes)) {
        $message = sprintf(
            'Error of type %s raised in file %s at line %d with message "%s"',
            $codes[$error['type']],
            $error['file'],
            $error['line'],
            $error['message']
        );
        $logger = LoggingHelper::getLogger();
        if (in_array($error['type'], array(32, 128))) {
            //These errors are warnings and should be logged at a lower level.
            $logger->addError($message);
        } else {
            $logger->addAlert($message);
        }
    }
});