proper web socket close

TanksServer/EasyWebSocket.cs

@@ -0,0 +1,53 @@
+using System.Net.WebSockets;
+using System.Threading;
+using Microsoft.Extensions.Logging;
+
+namespace TanksServer;
+
+internal abstract class EasyWebSocket
+{
+    private readonly TaskCompletionSource _completionSource = new();
+
+    private readonly ILogger _logger;
+    private readonly WebSocket _socket;
+    private readonly Task _readLoop;
+    private readonly ArraySegment<byte> _buffer;
+
+    protected EasyWebSocket(WebSocket socket, ILogger logger, ArraySegment<byte> buffer)
+    {
+        _socket = socket;
+        _logger = logger;
+        _buffer = buffer;
+        _readLoop = ReadLoopAsync();
+    }
+
+    public Task Done => _completionSource.Task;
+
+    private async Task ReadLoopAsync()
+    {
+        do
+        {
+            var response = await _socket.ReceiveAsync(_buffer, CancellationToken.None);
+            if (response.CloseStatus.HasValue)
+                break;
+
+            await ReceiveAsync(_buffer[..response.Count]);
+        } while (_socket.State == WebSocketState.Open);
+    }
+
+    protected abstract Task ReceiveAsync(ArraySegment<byte> buffer);
+
+    protected Task SendAsync(byte[] data)
+    {
+        _logger.LogTrace("sending {} bytes of data", _buffer.Count);
+        return _socket.SendAsync(data, WebSocketMessageType.Binary, true, CancellationToken.None);
+    }
+
+    public async Task CloseAsync()
+    {
+        _logger.LogDebug("closing socket");
+        await _socket.CloseAsync(WebSocketCloseStatus.NormalClosure, null, CancellationToken.None);
+        await _readLoop;
+        _completionSource.SetResult();
+    }
+}