Whenever we have an api that supports GET with a body, we always support the POST method too, as well as providing the body as a query_string parameter called `source`. Our REST spec should reflect this convention. FIxed them and introduced a hard check at parse time in our Java REST tests runner, which will cause the tests to fail if spec are not compliant.
Closes#9629
Honza Král
javanna
Clinton Gormley
Martijn van Groningen