ruby on rails 4 - Unknown format error when trying to respond_to format.xml -

i'm trying parse simple xml post request , send 200 status in response i'm receiving unknown format error, not understand why. action says processing / not xml. great!

actioncontroller::unknownformat (actioncontroller::unknownformat):   app/controllers/locations_controller.rb:171:in `vz_api'  started post "/vz_api" 127.0.0.1 @ 2014-06-25 19:52:27 -0400 processing locationscontroller#vz_api */*    def vz_api     require 'nokogiri'     xml_doc = nokogiri::xml(request.body.read)     vin = xml_doc.xpath("//vin").inner_text     @truck = truck.find_by(vin: vin)     @location = @truck.location     lat = xml_doc.xpath("//latitude").inner_text     lng = xml_doc.xpath("//longitude").inner_text     heading = xml_doc.xpath("//heading").inner_text     speed = xml_doc.xpath("//speed")[0].inner_text     @location.update_attributes(longitude: lng, latitude: lat, speed: speed, direction: heading)     respond_to |format|       format.xml # format.json         render :nothing => true, :status => :ok         # return true       end     end   end 

rails processing / not xml or json, why don't try following instead

remove respond_to block , have:

render :nothing => true, status: :ok