internal ResponseMediaTypeMatch SelectResponseMediaType(Type type, HttpRequestMessage request)
{
if (type == null)
{
throw new ArgumentNullException("type");
}
if (request == null)
{
throw new ArgumentNullException("request");
}
if (!CanWriteType(type))
{
return(null);
}
// Determine the best character encoding if we have any registered encoders.
// Note that it is ok for a formatter not to register any encoders in case it doesn't
// do any structured reading or writing.
Encoding characterEncodingMatch = SupportedEncodings.Any() ? SelectResponseCharacterEncoding(request) : null;
// Determine the best media type
MediaTypeMatch mediaTypeMatch = null;
// Match against media type mapping first
if (TryMatchMediaTypeMapping(request, out mediaTypeMatch))
{
mediaTypeMatch.SetEncoding(characterEncodingMatch);
return(new ResponseMediaTypeMatch(
mediaTypeMatch,
ResponseFormatterSelectionResult.MatchOnRequestWithMediaTypeMapping));
}
// Match against the accept header.
if (TryMatchSupportedMediaType(request, out mediaTypeMatch))
{
mediaTypeMatch.SetEncoding(characterEncodingMatch);
return(new ResponseMediaTypeMatch(
mediaTypeMatch,
ResponseFormatterSelectionResult.MatchOnRequestAcceptHeader));
}
// Match against request's content type
HttpContent requestContent = request.Content;
if (requestContent != null)
{
MediaTypeHeaderValue requestContentType = requestContent.Headers.ContentType;
if (requestContentType != null && TryMatchSupportedMediaType(requestContentType, out mediaTypeMatch))
{
mediaTypeMatch.SetEncoding(characterEncodingMatch);
return(new ResponseMediaTypeMatch(
mediaTypeMatch,
ResponseFormatterSelectionResult.MatchOnRequestContentType));
}
}
// No match at all.
// Pick the first supported media type and indicate we've matched only on type
MediaTypeHeaderValue mediaType = SupportedMediaTypes.FirstOrDefault();
mediaTypeMatch = new MediaTypeMatch(mediaType);
mediaTypeMatch.SetEncoding(characterEncodingMatch);
return(new ResponseMediaTypeMatch(
mediaTypeMatch,
ResponseFormatterSelectionResult.MatchOnCanWriteType));
}
