//partly according to: https://williambert.online/2013/06/allow-cors-with-localhost-in-chrome/
/// <summary>
/// Sets response headers to enable CORS.
/// </summary>
/// <param name="response">HTTP response.</param>
/// <returns>Modified HTTP response.</returns>
public static HttpListenerResponse WithCORS(this HttpListenerResponse response)
{
if (response == null)
{
throw new ArgumentNullException(nameof(response), "Response must not be null.");
}
response.WithHeader("Access-Control-Allow-Origin", "*");
response.WithHeader("Access-Control-Allow-Headers", "Cache-Control, Pragma, Accept, Origin, Authorization, Content-Type, X-Requested-With");
response.WithHeader("Access-Control-Allow-Methods", "GET, POST");
response.WithHeader("Access-Control-Allow-Credentials", "true");
return(response);
}
static void fromStream(HttpListenerRequest request, HttpListenerResponse response, Stream stream, string mime)
{
if (request.Headers.AllKeys.Count(x => x == BYTES_RANGE_HEADER) > 1)
{
throw new NotSupportedException("Multiple 'Range' headers are not supported.");
}
int start = 0, end = (int)stream.Length - 1;
//partial stream response support
var rangeStr = request.Headers[BYTES_RANGE_HEADER];
if (rangeStr != null)
{
var range = rangeStr.Replace("bytes=", String.Empty)
.Split(new string[] { "-" }, StringSplitOptions.RemoveEmptyEntries)
.Select(x => Int32.Parse(x))
.ToArray();
start = (range.Length > 0) ? range[0] : 0;
end = (range.Length > 1) ? range[1] : (int)(stream.Length - 1);
response.WithHeader("Accept-Ranges", "bytes")
.WithHeader("Content-Range", "bytes " + start + "-" + end + "/" + stream.Length)
.WithCode(HttpStatusCode.PartialContent);
response.KeepAlive = true;
}
//common properties
response.WithContentType(mime);
response.ContentLength64 = (end - start + 1);
//data delivery
try
{
stream.Position = start;
stream.CopyTo(response.OutputStream, Math.Min(MAX_BUFFER_SIZE, end - start + 1));
}
catch (Exception ex) when(ex is HttpListenerException) //request canceled
{
response.StatusCode = (int)HttpStatusCode.NoContent;
}
finally
{
stream.Close();
response.Close();
}
}
