compute.rb

        def request(params)
          begin
            response = @connection.request(params.merge({
              :headers  => {
                'Content-Type' => 'application/json',
                'Accept' => 'application/json',
                'X-Auth-Token' => @auth_token
              }.merge!(params[:headers] || {}),
              :path     => "#{@path}/#{@tenant_id}/#{params[:path]}",
              :query    => params[:query]
            }))
          rescue Excon::Errors::Unauthorized => error
            if error.response.body != 'Bad username or password' # token expiration
              @openstack_must_reauthenticate = true
              authenticate
              retry
            else # Bad Credentials
              raise error
            end
          rescue Excon::Errors::HTTPStatusError => error
            raise case error
              when Excon::Errors::NotFound
                Fog::Compute::OpenStack::NotFound.slurp(error)
              else
                error
              end
          end

          if !response.body.empty? and response.get_header('Content-Type') == 'application/json'
            response.body = Fog::JSON.decode(response.body)
          end

          response
        end