Allow extra parameters with load_and_authorize_resource

Question

I have 3 entities with the following relationships :

a Folder which can have multiple Participants - with firstname and lastname. A participant can be optionally linked to a User which has an email attribute (a user can have multiple participants)

The logic I want to achieve is the following : When creating a Folder, the API should allow to pass a list of participants.

{
    "folder": {
        "participants_attributes": [
            {
                "firstname": "Some",
                "lastname": "One",
                "client_attributes" : {
                   "email": "[email protected]"
                }
            },
            {
                "firstname": "Some",
                "lastname": "OneElse"
            }
        ]
    }
}

All the participants should be created and attached to the folder. If a participant has an email attached, we should either create a new user and attach it to the participant or attach the user if it already exists (email has a unique constraint)

Here are my models :

class Folder < ApplicationRecord
    has_many :participants


class Participant < ApplicationRecord
    belongs_to :user, optional: true

I initially planned to leverage the use of accepts_nested_attributes_for within my Folder and Participant models, and it worked well except for the use an existing user with the same email. I have been told that this logic should be handled at the folder controller level, so I try something like

 class FoldersController < ActionController::API
    load_and_authorize_resource
    

    def create
       participants_attributes = params.extract!(:participants_attributes)
       participants_attributes.each |p| do
          # the rest of the code processing the logic
       ...     
      @folder.save!
      render json: @folder
    end


    def create_params
          params.require(:folder).permit(
            participants_attributes: [
               :firstname, 
               :lastname, 
               { client_attributes: [:email] }
            ]
          )
    end

My problem is that the load_and_authorize_resource preload the folder entity with the params, resulting in the following error ActiveModel::UnknownAttributeError (unknown attribute 'participants_attributes' for Folder.)

How can I solve this ?