protected override Task <HttpResponseMessage> SendAsync(HttpRequestMessage request,
CancellationToken cancellationToken)
{
if (request.Method == HttpMethod.Get)
{
//if this resource has been updated, let the request proceed to the operation and set a new etag on the return
return(base.SendAsync(request, cancellationToken).ContinueWith(task =>
{
var resp = task.Result;
if (resp.IsSuccessStatusCode && resp.Content is ObjectContent)
{
IViewModelAuditable viewModelAuditable = resp.Content.ReadAsAsync <object>(cancellationToken).Result as IViewModelAuditable;
if (viewModelAuditable != null)
{
resp.Headers.CacheControl = new CacheControlHeaderValue {
Public = true
};
resp.Headers.ETag = new EntityTagHeaderValue(ETagGenerator.GeneratorETag(viewModelAuditable.LastUpdatedDateUtc));
resp.Content.Headers.LastModified = viewModelAuditable.LastUpdatedDateUtc;
}
}
return resp;
}, cancellationToken));
}
//if (request.Method == HttpMethod.Put || request.Method == HttpMethod.Post)
// //let the request processing continue; new etag value for resource; update response header
// if (IfMatchContainsStoredEtagValue(request))
// return base.SendAsync(request, cancellationToken).ContinueWith(task =>
// {
// var resp = task.Result;
// resp.Headers.ETag = new EntityTagHeaderValue(_eTagStore.UpdateETagFor(request.RequestUri));
// return resp;
// }, cancellationToken);
// //stop processing and return a 412/precondition failed; update response header
// else
// return taskFactory.StartNew(() =>
// {
// var resp = new HttpResponseMessage(HttpStatusCode.PreconditionFailed);
// resp.Headers.ETag = new EntityTagHeaderValue(_eTagStore.Fetch(request.RequestUri));
// return resp;
// }, cancellationToken);
//by default, let the request keep moving up the message handler stack
return(base.SendAsync(request, cancellationToken));
}