[5.3] Offer an "Attribute Casting" of encrypt

[alnutile]

This would allow the user to easily encrypt and decrypt a field by setting it to that cast

For example

    protected $casts = [
        'secret' => 'encrypt',
        'data' => 'array'
    ];

[alnutile]

Should I go update the docs? @taylorotwell

[lukepolo]

Awesome , I had written this as a trait numerous times ~

[alnutile]

:)

[djtarazona]

Should this be a "cast"? I've written something similar into my models but using a separate $encrypts property. With this implementation, to my understanding, you wouldn't be able to decrypt an attribute and then cast it to an interger? Or a decrypt and cast to an array?

My use case is storing OAuth tokens. I store the access token, refresh token, and expiration in an array and assign it to an attribute with the array cast. I then also mark that attribute as "encrypts" so that when settting, the array is serialized and then encrypted. When accessing the attribute, the value is decrypted and then deserialized to an array.

Edit: To address my use case, I've created #16457 to change this functionality.