How can I extend an existing request?

The expects() method can be used to add custom validation rules (and messages) for your custom field (or to overwrite the existing rules/messages for an existing field):

// Adding a custom field
\Aero\Admin\Http\Requests\Catalog\CreateProductRequest::expects('acme', 'required|string|max:255', [
    'acme.required' => 'The acme field is required.',
]);

// Making existing categories field required
\Aero\Admin\Http\Requests\Catalog\CreateProductRequest::expects('categories', 'required|array');

Parameters

Parameter	Type	Description
`$field`	`string`	The key of the field to validate.
`$rules`	`string\|array\|\Closure`	The rules to use when validating. If callback is supplied, it will receive the request as the argument.
`$messages`	`array\|null`	The messages for the rules, key's are of the form `{$field}.{$rule}`.