Where should body and headers be set?

[andreineculau]

Webmachine decision core and the resource callbacks (can) set headers almost anywhere, which easily leads to headers being set for HTTP status codes where they don't make sense, eg. https://github.com/basho/webmachine/issues/114

Proposed resolution
Mark possible headers as meta-data, and only set a subset of those as response headers at the end of the request processing flow ie. webmachine_decision_core:respond and finish_request resource callback. This would make respond and finish_request encapsulate logic around the HTTP status codes..

[andreineculau]

solved in v4
headers are only set, if undefined (i.e. unless the resource set a header outside of the decision diagram = don't overwrite)
headers are set, or supposed to be set along the diagram. on last headers are stringified from the operation.response.h (header objects) to operation.response.headers(unless a header is defined already)