请求帖子上的ActiveModel :: ForbiddenAttributesError rspec

Question

我有一个UserCourseRegistration表，该表属于User和Course表，而User和Course表通过UserCourseRegistration表为has_many。我的UserCourseRegistration控制器如下所示：

class UserCourseRegistrationsController < ApplicationController
  before_action :set_invite, only: [:edit, :show, :update, :destroy]

  def index
    @invite = UserCourseRegistration.new
  end

  def create
    @invite = UserCourseRegistration.new(invite_params)
    if @invite.save
      redirect_to '/user_course_registrations'
    else
      render :new, notice: @invite.errors 
    end
  end

  def show
  end

  def edit
  end

  def update
    if @invite.update(invite_params)
      redirect_to @invite
    else
      render :edit
    end
  end

  def destroy
    @invite.destroy
    respond_to do |format|
      format.json { render json: true }
    end
  end

  private

    def set_invite
      @invite = UserCourseRegistration.find(params[:id])
    end

    def invite_params
      params.require(:user_course_registration).permit(:course_id, :user_id)
    end
end

当我尝试在rspec中对create方法进行控制器测试时，给出以下消息：

  

失败/错误：发布：创建，参数：{user_course_registration：   @user_course_attributes}

     

ActiveModel :: ForbiddenAttributesError：   ActiveModel :: ForbiddenAttributesError

我的测试是：

before(:each) do
    @request.env["devise.mapping"] = Devise.mappings[:user]
    @current_user_admin = create(:admin)
    @current_user = create(:user)
    sign_in @current_user_admin
  end
describe "POST #create" do
    context 'user is admin' do
      before(:each) do
        @school = create(:school, user: @current_user_admin)
        @course = create(:course, user: @current_user_admin, school: @school)
        @user_course_attributes = attributes_for( :user_course_registration, 
                                                  user_id: @current_user_admin.id, 
                                                  course_id: @course.id
                                                  )

          post :create, params: { user_course_registration: @user_course_attributes }
        end

        it 'redirect to show' do
        expect(response).to have_http_status(302)
        expect(response).to redirect_to("/user_course_registration")
      end
    end
   end

那会是什么？