protected async override Task <HttpResponseMessage> SendAsync(
HttpRequestMessage request, CancellationToken cancellationToken)
{
if (!ValidateAcceptsSData(request.Headers.Accept))
{
// consumer does NOT want SData so let Web API handle this as is
return(await base.SendAsync(request, cancellationToken));
}
Uri originalUri = request.RequestUri;
// check if this server only specified some routes mapped to SData
if (TargetRoutPrefix != null && TargetRoutPrefix.Trim() != "" &&
!originalUri.AbsolutePath.StartsWith(TargetRoutPrefix, StringComparison.InvariantCultureIgnoreCase))
{
// there's a targeRoutePrefix specified so skip mapping if this
// URL doesn't start with the prefix
return(await base.SendAsync(request, cancellationToken));
}
// convert/translate SData query keys (where, startIndex, etc.)
Uri newUri = originalUri.TransformToSData();
request.RequestUri = newUri;
// replace consumer's Accept Header with OData nometadata so we get json in format we want
var origAccept = request.Headers.Accept;
request.Headers.Accept.Clear();
MediaTypeWithQualityHeaderValue noMetadataHeader = new MediaTypeWithQualityHeaderValue(JSON_MEDIA_TYPE);
noMetadataHeader.Parameters.Add(new NameValueWithParametersHeaderValue("odata", "nometadata"));
request.Headers.Accept.Add(noMetadataHeader);
// URL and Headers have been mapped to OData; we now have an OData request
var response = await base.SendAsync(request, cancellationToken);
if (ResponseIsValid(response))
{
// OData request was handled and is valid so now transform Content/Payload to SData
response.Content = new SDataContent(response, maps);
}
else if (errResponseBuilder != null)
{
// add the original accepts back
origAccept.ToList().ForEach(i => request.Headers.Accept.Add(i));
response = errResponseBuilder.BuildErrorResponse(request, response);
}
return(response);
}