I sometimes need to post larger JSON request payloads to my ASP.Net Core Controllers. The size of the payload warrants (at least in my opinion) compressing it. Because ASP.Net Core Controllers do not appear to support compressed request content out of the box, I've rolled my own middleware.
Implementing this was so trivial that I'm not sure if I'm missing something here. Either because there's a built-in way to achieve this or because I made some major mistake from a security- or performance standpoint?
public class GzipRequestContentEncodingMiddleware
{
public GzipRequestContentEncodingMiddleware(RequestDelegate next)
{
if (next == null)
throw new ArgumentNullException(nameof(next));
this.next = next;
}
private readonly RequestDelegate next;
private const string ContentEncodingHeader = "Content-Encoding";
private const string ContentEncodingGzip = "gzip";
private const string ContentEncodingDeflate = "deflate";
public async Task Invoke(HttpContext context)
{
if (context.Request.Headers.Keys.Contains(ContentEncodingHeader) &&
(context.Request.Headers[ContentEncodingHeader] == ContentEncodingGzip ||
context.Request.Headers[ContentEncodingHeader] == ContentEncodingDeflate))
{
var contentEncoding = context.Request.Headers[ContentEncodingHeader];
context.Request.Headers.Remove(ContentEncodingHeader);
var destination = new MemoryStream();
using (var decompressor = contentEncoding == ContentEncodingGzip
? (Stream) new GZipStream(context.Request.Body, CompressionMode.Decompress, true)
: (Stream) new DeflateStream(context.Request.Body, CompressionMode.Decompress, true))
{
await decompressor.CopyToAsync(destination);
}
destination.Seek(0, SeekOrigin.Begin);
context.Request.Body = destination;
context.Request.Headers["Content-Length"] = destination.Length.ToString(CultureInfo.InvariantCulture);
}
await next(context);
}
}