// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System.Buffers;
using System.Text;
using Microsoft.AspNetCore.Connections;
using Microsoft.AspNetCore.Http.Connections.Features;
namespace SignalRSamples.ConnectionHandlers;
public class MessagesConnectionHandler : ConnectionHandler
{
private ConnectionList Connections { get; } = new ConnectionList();
public override async Task OnConnectedAsync(ConnectionContext connection)
{
Connections.Add(connection);
var transportType = connection.Features.Get<IHttpTransportFeature>()?.TransportType;
await Broadcast($"{connection.ConnectionId} connected ({transportType})");
try
{
while (true)
{
var result = await connection.Transport.Input.ReadAsync();
var buffer = result.Buffer;
try
{
if (!buffer.IsEmpty)
{
// We can avoid the copy here but we'll deal with that later
var text = Encoding.UTF8.GetString(buffer.ToArray());
text = $"{connection.ConnectionId}: {text}";
await Broadcast(Encoding.UTF8.GetBytes(text));
}
else if (result.IsCompleted)
{
break;
}
}
finally
{
connection.Transport.Input.AdvanceTo(buffer.End);
}
}
}
finally
{
Connections.Remove(connection);
await Broadcast($"{connection.ConnectionId} disconnected ({transportType})");
}
}
private Task Broadcast(string text)
{
return Broadcast(Encoding.UTF8.GetBytes(text));
}
private Task Broadcast(byte[] payload)
{
var tasks = new List<Task>(Connections.Count);
foreach (var c in Connections)
{
tasks.Add(c.Transport.Output.WriteAsync(payload).AsTask());
}
return Task.WhenAll(tasks);
}
}
|