fun accept(contributor: AcceptHeaderContributor)

Register a custom accepted content types contributor. A contributor function takes ApplicationCall and a list of content types accepted according to HttpHeaders.Accept header or provided by the previous contributor if exists. Result of this contributor should be a list of accepted content types with quality. A contributor could either keep or replace input list of accepted content types depending on use-case. For example a contributor taking format=json request parameter could replace the original content types list with the specified one from the uri argument. Note that the returned list of accepted types will be sorted according to quality using sortedByQuality so a custom contributor may keep it unsorted and should not rely on input list order.