// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
app.Use((context, next) =>
{
context.Response.Headers["Access-Control-Allow-Origin"] = "*";
return(next.Invoke());
});
app.UseCors(builder => builder
.AllowAnyOrigin()
.AllowAnyMethod()
.AllowAnyHeader());
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseHttpsRedirection();
app.UseRouting();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllers();
});
var webSocketOptions = new WebSocketOptions()
{
KeepAliveInterval = TimeSpan.FromSeconds(120),
ReceiveBufferSize = 4 * 1024
};
webSocketOptions.AllowedOrigins.Add("*");
app.UseWebSockets(webSocketOptions);
app.Use(async(context, next) =>
{
if (context.Request.Path == "/ws")
{
if (context.WebSockets.IsWebSocketRequest)
{
WebSocket webSocket = await context.WebSockets.AcceptWebSocketAsync();
await ProcessClientMessages(context, webSocket);
}
else
{
context.Response.StatusCode = 400;
}
}
else
{
await next();
}
});
ChannelHub.StartCleanupThread();
}
private async Task HandleClientMessage(ChannelHub.ConnectedClient cc, string command, string payload)
{
if (command == "ID") // Set client Id
{
cc.ClientId = payload;
}
else if (command == "JOIN")
{
await ChannelHub.AddClientToChannelAsync(cc, payload);
}
else if (command == "LEAVE")
{
ChannelHub.RemoveClientFromChannel(cc, payload);
}
else if (command == "MSG")
{
var messageData = System.Text.Json.JsonSerializer.Deserialize <ChannelHub.CommandMessageData>(payload);
if (messageData != null)
{
ChannelHub.SendMessageFromClientToChannel(cc, messageData.Channel, messageData.Data);
}
}
}
private async Task ProcessClientMessages(HttpContext context, WebSocket webSocket)
{
var cc = new ChannelHub.ConnectedClient()
{
WebSocketClient = webSocket,
Channels = new List <string>(),
ClientId = null,
BufferedData = new List <byte>(),
SendingData = false
};
var message = await ReceiveFullMessage(webSocket, CancellationToken.None);
WebSocketReceiveResult result = message.Item1;
while (result != null && !result.CloseStatus.HasValue)
{
// Process message
// Command syntax: Command|Length payload|Payload
if (result.MessageType == WebSocketMessageType.Text)
{
var data = ASCIIEncoding.UTF8.GetString(message.Item2.ToArray());
var dataLeft = data.Length;
while (dataLeft > 0)
{
var indexOfSeperator = data.IndexOf("|");
if (indexOfSeperator <= 0)
{
break; // No first separator
}
var command = data.Substring(0, indexOfSeperator);
var indexOfSecondSeperator = data.IndexOf("|", indexOfSeperator + 1);
if (indexOfSecondSeperator <= 0)
{
break; // No second separator
}
if (!Int32.TryParse(data.Substring(indexOfSeperator + 1, indexOfSecondSeperator - (indexOfSeperator + 1)), out var dataLength))
{
break; // Message length is not a number
}
var indexEndOfMessage = dataLength + indexOfSeperator + 1;
if (data.Length < indexEndOfMessage)
{
break; // Payload part is smaller than what the header is saying
}
await HandleClientMessage(cc, command, data.Substring(indexOfSecondSeperator + 1, dataLength));
data = data.Substring(indexEndOfMessage);
}
}
message = await ReceiveFullMessage(webSocket, CancellationToken.None);
result = message.Item1;
}
if (result == null)
{
await webSocket.CloseAsync(WebSocketCloseStatus.MessageTooBig, "Buffer full", CancellationToken.None);
}
else
{
await webSocket.CloseAsync(result.CloseStatus.Value, result.CloseStatusDescription, CancellationToken.None);
}
List <string> unsubChannels = null;
lock (cc.Channels)
unsubChannels = cc.Channels.ToList();
foreach (var channel in unsubChannels)
{
ChannelHub.RemoveClientFromChannel(cc, channel);
}
}