var req *http.Request

		BeforeEach(func() {
			req = newTestRequest(validUpdateRequest)
			req.Form = url.Values{":process_guid": []string{expectedProcessGuid}}
		})

		Context("when everything succeeds", func() {
			BeforeEach(func(done Done) {
				defer close(done)
				handler.Update(responseRecorder, req)
			})

			It("calls UpdateDesiredLRP on the BBS", func() {
				Expect(fakeLegacyBBS.UpdateDesiredLRPCallCount()).To(Equal(1))
				_, processGuid, update := fakeLegacyBBS.UpdateDesiredLRPArgsForCall(0)
				Expect(processGuid).To(Equal(expectedProcessGuid))
				Expect(update).To(Equal(expectedUpdate))
			})

			It("responds with 204 NO CONTENT", func() {
				Expect(responseRecorder.Code).To(Equal(http.StatusNoContent))
			})

			It("responds with an empty body", func() {
				Expect(responseRecorder.Body.String()).To(Equal(""))
			})
		})

		Context("when the :process_guid is blank", func() {
			BeforeEach(func() {