public override MiddlewareContinuation Invoke(ICurrentHttpRequest request, IHttpWriter writer)
{
if (request.IsNotHttpMethod("GET", "HEAD"))
{
return(MiddlewareContinuation.Continue());
}
var file = _files.Find(request.RelativeUrl());
if (file == null)
{
return(MiddlewareContinuation.Continue());
}
if (_settings.DetermineStaticFileRights(file) != AuthorizationRight.Allow)
{
return(MiddlewareContinuation.Continue());
}
if (request.IsHead())
{
return(new WriteFileHeadContinuation(writer, file, HttpStatusCode.OK));
}
if (request.IfMatchHeaderDoesNotMatchEtag(file))
{
return(new WriteStatusCodeContinuation(writer, HttpStatusCode.PreconditionFailed, "If-Match test failed"));
}
if (request.IfNoneMatchHeaderMatchesEtag(file))
{
return(new WriteFileHeadContinuation(writer, file, HttpStatusCode.NotModified));
}
if (request.IfModifiedSinceHeaderAndNotModified(file))
{
return(new WriteFileHeadContinuation(writer, file, HttpStatusCode.NotModified));
}
if (request.IfUnModifiedSinceHeaderAndModifiedSince(file))
{
return(new WriteStatusCodeContinuation(writer, HttpStatusCode.PreconditionFailed, "File has been modified"));
}
return(new WriteFileContinuation(writer, file));
}