Ooui-tws-port/Ooui/Server.cs

93 lines
3.8 KiB
C#

using System;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Net;
using System.Net.WebSockets;
namespace Ooui
{
public class Server
{
public Task RunAsync (string listenerPrefix)
{
return RunAsync (listenerPrefix, CancellationToken.None);
}
public async Task RunAsync (string listenerPrefix, CancellationToken token)
{
var listener = new HttpListener ();
listener.Prefixes.Add (listenerPrefix);
listener.Start ();
Console.WriteLine ($"Listening at {listenerPrefix}...");
while (!token.IsCancellationRequested) {
var listenerContext = await listener.GetContextAsync ();
if (listenerContext.Request.IsWebSocketRequest) {
ProcessWebSocketRequest (listenerContext, token);
}
else {
listenerContext.Response.StatusCode = 400;
listenerContext.Response.Close ();
}
}
}
async void ProcessWebSocketRequest (HttpListenerContext listenerContext, CancellationToken token)
{
WebSocketContext webSocketContext = null;
try {
webSocketContext = await listenerContext.AcceptWebSocketAsync(subProtocol: null);
Console.WriteLine ("Accepted WebSocket: {0}", webSocketContext);
}
catch (Exception e) {
listenerContext.Response.StatusCode = 500;
listenerContext.Response.Close();
Console.WriteLine ("Failed to accept WebSocket: {0}", e);
return;
}
WebSocket webSocket = null;
try {
webSocket = webSocketContext.WebSocket;
var receiveBuffer = new byte[1024];
while (webSocket.State == WebSocketState.Open && !token.IsCancellationRequested) {
var receiveResult = await webSocket.ReceiveAsync(new ArraySegment<byte>(receiveBuffer), token);
if (receiveResult.MessageType == WebSocketMessageType.Close) {
await webSocket.CloseAsync (WebSocketCloseStatus.NormalClosure, "", token);
}
else if (receiveResult.MessageType == WebSocketMessageType.Binary) {
await webSocket.CloseAsync (WebSocketCloseStatus.InvalidMessageType, "Cannot accept binary frame", token);
}
else {
var size = receiveResult.Count;
while (!receiveResult.EndOfMessage) {
if (size >= receiveBuffer.Length) {
await webSocket.CloseAsync (WebSocketCloseStatus.MessageTooBig, "Message too big", token);
return;
}
receiveResult = await webSocket.ReceiveAsync (new ArraySegment<byte>(receiveBuffer, size, receiveBuffer.Length - size), token);
size += receiveResult.Count;
}
var receivedString = Encoding.UTF8.GetString (receiveBuffer, 0, size);
Console.WriteLine ("RECEIVED: {0}", receivedString);
var outputBuffer = new ArraySegment<byte> (Encoding.UTF8.GetBytes ($"You said: {receivedString}"));
await webSocket.SendAsync (outputBuffer, WebSocketMessageType.Text, true, token);
}
}
}
catch (Exception e) {
Console.WriteLine ("Exception: {0}", e);
}
finally {
webSocket?.Dispose();
}
}
}
}