DnsHttpsClient.cs

using System;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;
using Waher.Events;
 
namespace Waher.Networking.DNS.Communication
{
    public class DnsHttpsClient : DnsClient
    {
        private Uri uri;
 
        public DnsHttpsClient(Uri Uri)
            : base()
        {
            this.uri = Uri;
            this.Init();
        }
 
        public Uri Uri
        {
            get => this.uri;
            set => this.uri = value;
        }
 
        protected override async Task SendAsync(byte[] Message, IPEndPoint Destination)
        {
            using (HttpClient HttpClient = new HttpClient()
            {
                Timeout = TimeSpan.FromMilliseconds(10000)
            })
            {
                using (HttpRequestMessage Request = new HttpRequestMessage()
                {
                    RequestUri = this.uri,
                    Method = HttpMethod.Post
                })
                {
                    Request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/dns-message"));
                    Request.Content = new ByteArrayContent(Message);
                    Request.Content.Headers.ContentType = new MediaTypeHeaderValue("application/dns-message");
                    
                    HttpResponseMessage Response = await HttpClient.SendAsync(Request);
 
                    if (Response.IsSuccessStatusCode)
                    {
                        byte[] Bin = await Response.Content.ReadAsByteArrayAsync();
 
                        await this.ReceiveBinary(Bin);
 
                        try
                        {
                            DnsMessage DnsResponse = new DnsMessage(Bin);
                            await this.ProcessIncomingMessage(DnsResponse);
                        }
                        catch (Exception ex)
                        {
                            Log.Error("Unable to process DNS packet: " + ex.Message);
                        }
                    }
                    else
                    {
                        ushort ID = Message[0];
                        ID <<= 8;
                        ID |= Message[1];
 
                        await this.ProcessMessageFailure(ID);
                    }
                }
            }
        }
 
    }
}