In Carbon, YANGTOOLS-663 introduced implicit input and output for Yang RPCs.

Previously, Restconf RPC behavior was different between missing and empty elements. Namely, missing input statement required no data, empty input required '{"input":{}}' as data. Also, missing output resulted in no response text, empty output resulted in '{"output":{}}'.

The output difference is not relevant to CSIT tests (the text was not checked). But the input difference is relevant, as empty data now fails [0].

This Bug is for Restconf to decide whether empty data is to be accepted, to make calls backward compatible with Boron-SR2.

If it is decided that Carbon will keep current backward incompatibility, the error message should be fixed anyway (from 500 to 400 with relevant message).

[0] https://logs.opendaylight.org/releng/jenkins092/controller-csit-3node-clustering-all-carbon/242/archives/log.html.gz#s1-s8-t2-k2-k4-k7-k1