[hello][WiP] refactor the code to simplify the call handling
[hello][WiP] refactor the code to simplify the call handling

Summary: branch yang

Test Plan: tetrapak test

Reviewers: aschultz, skattelmann, vtarasen

Reviewed By: skattelmann

CC: mkraemer, aschultz

Differential Revision: https://review.tpip.net/D1342

travelping/hello