koseven/system/guide/ko7/errors.md

Error/Exception Handling

Koseven provides both an exception handler and an error handler that transforms errors into Error_Exceptions using PHP's ErrorException class. Many details of the error and the internal state of the application is displayed by the handler:

1. Exception class
2. Error level
3. Error message
4. Source of the error, with the error line highlighted
5. A debug backtrace of the execution flow
6. Included files, loaded extensions, and global variables

Example

Click any of the links to toggle the display of additional information:

{{userguide/examples/error}}

Disabling Error/Exception Handling

If you do not want to use the internal error handling, you can disable it (highly discouraged) when calling [KO7::init]:

Kohana::init(array('errors' => FALSE));

Error Reporting

By default, Koseven displays all errors and warnings. This is set using error_reporting:

error_reporting(E_ALL);

When you application is live and in production, a more conservative setting is recommended, such as ignoring notices:

error_reporting(E_ALL & ~E_NOTICE);

If you get a white screen when an error is triggered, your host probably has disabled displaying errors. You can turn it on again by adding this line just after your error_reporting call:

ini_set('display_errors', TRUE);

Errors should always be displayed, even in production, because it allows you to use exception and error handling to serve a nice error page rather than a blank white screen when an error happens.

HTTP Exception Handling

Koseven comes with a robust system for handing http errors. It includes exception classes for each http status code. To trigger a 404 in your application (the most common scenario):

throw HTTP_Exception::factory(404, 'File not found!');

To register error pages for these, using 404 as an example:

class HTTP_Exception_404 extends Kohana_HTTP_Exception_404 {

    public function get_response()
    {
        $response = Response::factory();

        $view = View::factory('errors/404');

        // We're inside an instance of Exception here, all the normal stuff is available.
        $view->message = $this->getMessage();

        $response->body($view->render());

        return $response;
    }

}

Deprecation "Error"

Koseven has a built-in function for deprecating code. If one of the deprecated function is used, it get's logged into your configured Log File.

It accepts two parameters:

1. (required) version number the function got deprecated in e.g "4.0"
2. (optional) replacement function

Here is a example of deprecating function "test" with function "test2" as replacement

public static function test
{
    // This got deprecated in v. 4.0
    KO7::deprecate('4.0', 'test2');
}

The above will log the following line every time the "test" function get's called:

YYYY-MM-DD HH:MM:SS --- WARNING: Function "test" inside class <class> is deprecated since version 4.0 and will be removed within the next major release. Please consider replacing it with "test2". in <file>:<line>