Simple proxy service for Nuget.org

NugetProxy.cs

using Microsoft.AspNetCore.Http;
using System;
using System.Linq;
using System.Collections.Generic;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

namespace VTB.Portal.NugetProxy
{
    public static class Proxy
    {
        const string apiUrl = "https://api.nuget.org";

        static HttpClientHandler handler = new HttpClientHandler
        {
            PreAuthenticate = false,
            SslProtocols = System.Security.Authentication.SslProtocols.Tls12,
            AllowAutoRedirect = true,
            CheckCertificateRevocationList = false,
            ServerCertificateCustomValidationCallback = (_,x,y,z) => true,
            MaxConnectionsPerServer = 50,
            AutomaticDecompression = System.Net.DecompressionMethods.GZip | System.Net.DecompressionMethods.Deflate,
            UseCookies = true,
            UseProxy = false
        };

        static readonly HttpClient httpClient = new HttpClient(handler);

        public static async Task Process(HttpContext ctx)
        {
            var req = ctx.Request;
            var url = apiUrl + req.Path.ToString() + req.QueryString.ToString();
            Console.WriteLine($"{req.Method}: {url} from {ctx.Connection.RemoteIpAddress}");
            using (var message = new HttpRequestMessage(new HttpMethod(req.Method), url))
            {
                if (message.Method == HttpMethod.Post || message.Method == HttpMethod.Put)
                {
                    message.Content = new StreamContent(req.Body);
                }

                foreach (var hh in req.Headers.Keys)
                {
                    var header = hh.ToLowerInvariant();
                    if (header == "host" || header == "referer")
                        continue;

                    var h = req.Headers[header].ToArray();
                    Console.WriteLine($"{header}: {h.First()}");
                    message.Headers.TryAddWithoutValidation(header, h);
                }

                // send request to nuget.org
                var resp = await httpClient.SendAsync(message, HttpCompletionOption.ResponseHeadersRead)
                    .ConfigureAwait(false);

                ctx.Response.StatusCode = (int)resp.StatusCode;

                foreach(var header in resp.Headers)
                {
                    ctx.Response.Headers[header.Key] = header.Value.ToArray();
                }

                using (var body = await resp.Content.ReadAsStreamAsync().ConfigureAwait(false))
                {
                    if (resp.StatusCode > System.Net.HttpStatusCode.Accepted)
                    {
                        Console.WriteLine($"ERR {resp.StatusCode.ToString()}");
                    }

                    await body.CopyToAsync(ctx.Response.Body).ConfigureAwait(false);
                }
            }

        }
    }
}