Custom Error Messages

There are cases that especially for validation purposes we need a custom error message to the end user.

Fortunately this is possible when we are using callbacks with Grocery CRUD ErrorMessage class.

For example, let's say that we would like to provide an error message when the user adds the 'Rejected' status without a message. The callback will look like this:

$crud->callbackBeforeInsert(function ($stateParameters) {
    if ($stateParameters->data['status'] === 'Rejected' && $stateParameters->data['message'] === '') {
        // The error message as a return parameter is only available at Enterprise version
        $errorMessage = new \GroceryCrud\Core\Error\ErrorMessage();
        return $errorMessage->setMessage("You can't add a Rejected status without a message\n");
    }

    return $stateParameters;
});

As you can see from the above scenario we have two cases:

The first one (if statement is false) is simply returning $stateParameters. That means that we will continue the insert as expected.
The second one (if statement is true) we are returning an error message that will not continue to the insert and instead will show an error message.

The ErrorMessage class as a return value is available to the following functions:

callbackBeforeInsert
callbackBeforeUpdate
callbackBeforeDelete
callbackBeforeUpload
callbackInsert
callbackUpdate
callbackDelete
callbackUpload

and also the functions:

callbackAfterInsert,
callbackAfterUpdate
callbackAfterDelete
callbackAfterUpload

However, you will need to be careful when using the error messages on after callbacks as you will need to manually revert the change if you wish so.

Example

$crud->setTable('orders');
$crud->setSubject('Order', 'Orders');
$crud->setRelation('customerNumber','customers','contactLastName');

$callbackWithValidation = function ($stateParameters) {
    if ($stateParameters->data['status'] === 'On Hold' && empty($stateParameters->data['comments'])) {
        // The error message as a return parameter is only available at Enterprise version
        $errorMessage = new \GroceryCrud\Core\Error\ErrorMessage();
        return $errorMessage->setMessage("You can't add an \"On Hold\" status without a comment\n");
    }

    return $stateParameters;
};

$crud->callbackBeforeInsert($callbackWithValidation);
$crud->callbackBeforeUpdate($callbackWithValidation);

$output =  $crud->render();