NoMethodError: undefined method `get' for RSpec

First of all, this is my first experience with ruby. At this moment, I'm creating tests for the a Controller called Exporter in my application. The method of the Controller I want to test is this:

def export_as_json(equipments)
    equipments_json = []
    equipments.each {|equipment|
        equipment_json = {
            :id => equipment.id,
            :title => equipment.title,
            :description => equipment.description,
            :category => equipment.category_id
        }
        equipments_json << equipment_json
    }

    respond_to do |format|
      format.json { render :json =>equipments_json }
    end
end

So, when I try to create a request for this method using this:

RSpec.describe ExporterController, type: :controller do
  get '/equipments/all', headers: { 'CONTENT_TYPE' => 'application/json' }, format: :json
  expect(response.response).to eq(200)
end

inside the exporter_controller_test.rb file I'm receiving this error:

NoMethodError: undefined method `get' for RSpec::ExampleGroups::ExporterController:Class