Download a file using Rails 4, Strong Parameters and Carrierwave

I am porting an application that uses Carrierwave for Rails 4, but I have problems with strong parameters. I have a model with

accepts_nested_attributes_for :photos

Here's how the uploaded images are transferred:

{
    # ...
    "model"=>
    {
        # ...
        "photos_attributes"=>
        {
            "1362752177921"=>
            {
                "image"=>"test.jpg",
            }
        }
    }
}

However, I cannot figure out how to write the parameters that will take photos_attributes.

I tried .permit(photos_attributes: []), but it just skips them when I use permit!, uuidwhich is created before the save does not appear in SQL, and this is the second problem:

photos.uuid may not be NULL: INSERT INTO "photos" ("created_at", "model_id", "image", "title", "updated_at") VALUES (?, ?, ?, ?, ?)

There is no documentation on strong parameters here, and I don’t even know how to do it.

Update This worked with nested attributes:

params.permit( ..., :photos_attributes => ['id', 'title', 'image', '_destroy'])

, Rails 4 Carrierwave Nested Form. . ( _) Rails 3.