Laravel 5.6 Validation Array Data - laravel

Question

When validating a request data, we are getting the result filtered out by the rules. For example, the following request:
$this->post(route('test'), [
'foo' => 'bar',
'john' => 'doe'
]);
And in my controller, I have the following:
$data = request()->validate([
'foo' => 'required|string'
]);
Then if I perform a dd($data);, I would get the following:
array:1 [
"foo" => "bar"
]
So far so good. However, when working with arrays, for example, the following request:
$this->post(route('test'), [
'foo' => 'bar',
'names' => [
'en' => 'Product',
'fr' => 'Produit',
'john' => 'Doe'
]
]);
And then in my controller, I have the following:
$data = request()->validate([
'foo' => 'required|string',
'names' => 'array',
'names.en' => 'required|string',
'names.fr' => 'required|string'
]);
It would return the following $data:
array:2 [
"foo" => "bar"
"names" => array:3 [
"en" => "Product"
"fr" => "Produit"
"john" => "doe"
]
]
Now my questions are:
Why is 'john' => 'doe' in my names key when I don't have it in my validation rules?
Is there a way to remove unspecified array keys from the data?
Update
I've tested the suggestion of #JonasStaudenmeir, however the result is not what I expected.
Request:
$this->post(route('test'), [
'names' => [
'en' => 'Doe',
'fr' => 'John'
]
]);
Controller:
$rules = [
'names' => 'array',
'names.en' => 'string'
];
dd(request()->only(array_keys($rules));
Expected Output:
array:1 [
"names" => array:2 [
"en" => "Doe"
]
]
Actual Output:
array:1 [
"names" => array:2 [
"fr" => "John"
"en" => "Doe"
]
]

Answer 1

For cases with only nested rules ('names.en') but no parent rule ('names'),
this will be fixed in 5.7: https://github.com/laravel/framework/pull/23708
Until then you can use this workaround:
$data = request()->only(array_keys($rules));
If you do you have a parent rule, this would be much more complicated to achieve.
I would argue that receiving the whole 'names' array in the validated data can be seen as the expected behavior. The idea is that the validator returns the data for each rule. In your case it returns the data for the 'names' => 'array' rule, which is the whole 'names' array.