What is the best way to compress a request to asp.net core 2 site using HttpClient?

Question

I am sending request that can be significantly big(~1Mb) and I am seeing a large delay betweeen when I make the request and when asp.net core logs that it is handling the request. I think I can cut down this time by compressing the request to asp using gzip.

Below is the fairly straight forward way that I am making requests without compression. What is the proper way to implement Gzip request compression on the client requesting side, and once I implement it on the client, what do I need to do for the server side?

using (HttpResponseMessage response = client.PostAsync("Controller/Action", httpContent).Result)
{
    if (response.StatusCode != System.Net.HttpStatusCode.OK)
    {

        throw new Exception(string.Format("Invalid responsecode for http request response {0}: {1}", response.StatusCode, response.ReasonPhrase));
    }
}

Answer 1

So I got it to work with simple middleware on the server side and not too much work on the client side. I used CompressedContent.cs from WebAPIContrib, as Rex suggested in the comments of his answer, and made the request as shown below. The whole throw-exception-if-not-OK is because I am using Polly wrapped around my request with a Retry and wait policy.

Client Side:

using (var httpContent = new StringContent(stringPayload, Encoding.UTF8, "application/json"))
using (var compressedContent = new CompressedContent(httpContent, "gzip"))
using (HttpResponseMessage response = client.PostAsync("Controller/Action", compressedContent).Result)
{
    if (response.StatusCode != System.Net.HttpStatusCode.OK)
    {
        throw new Exception(string.Format("Invalid responsecode for http request response {0}: {1}", response.StatusCode, response.ReasonPhrase));
    }
}

Then on the server side I created a simple piece of middleware that wraps the request body stream with the Gzip stream. To use it, you need to add the line app.UseMiddleware<GzipRequestMiddleware>(); before the call to app.UseMvc(); in your Startup.cs's Configure method.

public class GzipRequestMiddleware
{
    private readonly RequestDelegate next;
    private const string ContentEncodingHeader = "Content-Encoding";
    private const string ContentEncodingGzip = "gzip";
    private const string ContentEncodingDeflate = "deflate";

    public GzipRequestMiddleware(RequestDelegate next)
    {
        this.next = next ?? throw new ArgumentNullException(nameof(next));
    }

    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];
            var decompressor = contentEncoding == ContentEncodingGzip ? (Stream)new GZipStream(context.Request.Body, CompressionMode.Decompress, true) : (Stream)new DeflateStream(context.Request.Body, CompressionMode.Decompress, true);
            context.Request.Body = decompressor;
        }
        await next(context);
    }
}

Answer 2

You may need to enable compression as shown below

var handler = new HttpClientHandler();  
if (handler.SupportsAutomaticDecompression)  
{
    handler.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
}

var client = new HttpClient(handler);  

MSDN Reference: Using automatic decompression with HttpClient