c# - 通过同一 session 进行 Telegram 客户端更新和 API 请求

Question

我正在编写一个自定义的 C# Telegram 客户端，从 TLSharp 开始并对其进行修改以支持第 54 层。

我想同时处理从 Telegram 服务器接收更新和使用 API 而无需打开单独的 session 来执行此操作。

问题基本上是对连接到 Telegram 服务器的套接字的多线程访问。

这是方案:

TelegramClient <-------- socket_1[(session_1)] --------> TelegramServer

问题是为了不断从 Telegram 服务器接收更新，我使用了一个 while(true) 循环基本上被概括为:

while(true){
    data_cipher = await socket_1.receive() // listen for new stuff from the socket_1
    data_plain  = decrypt(data_cipher)  // decrypt 
    processUpdate(data_plain)  // process the update
}

现在，如果我想要，例如，查询 Telegram 服务器以获取我注册的所有聊天列表，我有访问 socket_1 以发送此请求，并等待答复，但 socket_1 正在监听中，我显然无法访问它。

一个解决方案可能是使用请求向量，在收到更新后将对其进行处理，这个想法是这样的:

List<Request> pending_requests = new List<Request>() // list of requests added by another thread 

    while(true){

        data_cipher = await socket_1.receive() // listen for new stuff from the socket_1
        data_plain  = decrypt(data_cipher)  // decrypt 
            processUpdate(data_plain)  // process the update

        if(pending_requests.Count != 0){
            foreach(Request r in pending_requests ){
                     processRequest(r)
                }
            }
    }

这个解决方案非常糟糕，因为我们只在更新后处理请求，所以没有更新 = 没有处理请求......

另一种可能性是按照这样的方案使用某种锁定机制:

//Thread_updater
//--------------------------------------------
while(true){

        lock(socket_1){
    data_cipher = await socket_1.receive() // listen for new stuff from the socket_1
    }

    data_plain  = decrypt(data_cipher)  // decrypt 
        handleUpdate(data_plain)  // process the update

}
--------------------------------------------


//Thread_requests
//--------------------------------------------
Request r = new Request(<stuff>);

lock(socket_1){
   await sendRequest(r,socket_1)
}

--------------------------------------------

最大的问题是，一旦 Thread_updater 获取了锁，它将永远不会释放锁，直到收到更新...这基本上是和以前一样的问题。我也尝试过使用 CancellationTasks 或 Socket Timeout，但我觉得我走错了路。

是否有优雅的解决方案/模式来巧妙地处理这个问题？如前所述，我不想打开 2 个 session ，因为它在逻辑上是错误的(这就像有两个客户端来处理接收更新和发送消息一样)。

Answer 1

有更简单的方法可以做到这一点。

这是我在 VB.net 中所做的，但在 C# 中也应该适用。

• 设置套接字并连接到 Telegram 服务器，监听数据
• 接收到的缓冲数据
• 处理接收到的数据 - 解码从 Telegram 接收到的 TL 类型并存储/响应，即发送消息以响应您收到的内容
• 在收听的同时，您还可以通过同一个套接字发送消息

示例代码

区域“变量”

    Const BUFFER_SIZE = 1024 * 64

    Private soc As Socket
    Private ep As EndPoint
    Private connected As Boolean
    Private efSent As Boolean
    Private are As New AutoResetEvent(False)
#End Region

#Region "Network"
    Public Sub Connect(Optional ip As String = "149.154.167.40", Optional port As Integer = 443)
        soc = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp) With {.SendBufferSize = BUFFER_SIZE, .SendTimeout = 3000}

        Try
            ep = GetIPEndPointFromHostName(ip, port)

            Dim arg = New SocketAsyncEventArgs With {.RemoteEndPoint = ep, .UserToken = "Connect_ARGS"}
            AddHandler arg.Completed, AddressOf IO_Handler

            While Not connected
                Try
                    If Not soc.ConnectAsync(arg) Then
                        IO_Handler(soc, arg)
                    End If

                    are.WaitOne(4000)
                Catch ex As Exception
                    Thread.Sleep(1000)
                End Try
            End While

        Catch ex As Exception
            Log("Connect: " & ex.ToString, ConsoleColor.Red, True)
        End Try

        ReadData()
    End Sub

    Public Sub Disconnect()
        connected = False
        loggedin = False

        soc.Disconnect(False)
        soc = Nothing

        Log("Disconnect", ConsoleColor.DarkYellow, True, True, True)
    End Sub

    Private Sub Send(m As PlainMessage)
        SendData(m.data, True)
    End Sub

    Private Sub Send(m As EncryptedMessage)
        SendData(m.data, True)
    End Sub

    Private Sub SendData(b() As Byte, Optional read As Boolean = False)
        b = TCPPack(b)

        Dim arg = New SocketAsyncEventArgs With {.RemoteEndPoint = ep, .UserToken = "Send_ARGS"}
        AddHandler arg.Completed, AddressOf IO_Handler
        arg.SetBuffer(b, 0, b.Length)

        Try
            If Not soc.SendAsync(arg) Then
                IO_Handler(soc, arg)
            End If
        Catch ex As Exception
            Log("SendData: " & ex.ToString, ConsoleColor.Red)
        End Try
    End Sub

    Private Sub IO_Handler(sender As Object, e As SocketAsyncEventArgs)
        Select Case e.SocketError
            Case SocketError.Success
                Select Case e.LastOperation
                    Case SocketAsyncOperation.Connect 'A socket Connect operation.
                        connected = True
                        Log("Connected to " & e.ConnectSocket.RemoteEndPoint.ToString, ConsoleColor.Green)
                        are.Set()
                    Case SocketAsyncOperation.Disconnect
                        connected = False
                        RaiseEvent Disconneted()
                    Case SocketAsyncOperation.Receive 'A socket Receive operation.
                        If e.BytesTransferred = 0 Then 'no pending data
                            Log("The remote end has closed the connection.")
                            If connected Then
                                ReadData()
                            End If

                            connected = False
                            loggedin = False

                            Exit Sub
                        End If
                        HandleData(e)
                End Select
            Case SocketError.ConnectionAborted
                RaiseEvent Disconneted()
        End Select
    End Sub

    Private Function GetIPEndPointFromHostName(hostName As String, port As Integer) As IPEndPoint
        Dim addresses = System.Net.Dns.GetHostAddresses(hostName)
        If addresses.Length = 0 Then
            Log("Unable to retrieve address from specified host name:  " & hostName, ConsoleColor.Red)
            Return Nothing
        End If
        Return New IPEndPoint(addresses(0), port)
    End Function

    Private Function TCPPack(b As Byte()) As Byte()
        Dim a = New List(Of Byte)
        Dim len = CByte(b.Length / 4)

        If efSent = False Then 'TCP abridged version
            efSent = True
            a.Add(&HEF)
        End If

        If len >= &H7F Then
            a.Add(&H7F)
            a.AddRange(BitConverter.GetBytes(len)) '
        Else
            a.Add(len)
        End If

        a.AddRange(b) 'data, no sequence number, no CRC32

        Return a.ToArray
    End Function

    Private Sub ReadData()
        Dim arg = New SocketAsyncEventArgs With {.RemoteEndPoint = ep, .UserToken = "Read_ARGS"}
        AddHandler arg.Completed, AddressOf IO_Handler

        Dim b(BUFFER_SIZE - 1) As Byte
        arg.SetBuffer(b, 0, BUFFER_SIZE)

        Try
            If Not soc.ReceiveAsync(arg) Then
                IO_Handler(soc, arg)
            End If
        Catch ex As Exception
            Log("ReadMessages: " & ex.ToString, ConsoleColor.Red)
        End Try
    End Sub

    Private Sub HandleData(e As SocketAsyncEventArgs)
        Log("<< " & B2H(e.Buffer, 0, e.BytesTransferred), ConsoleColor.DarkGray, True, logTime:=False)
        Try
            Dim len As Integer = e.Buffer(0)
            Dim start = 1

            If len = &H7F Then
                len = e.Buffer(1)
                len += e.Buffer(2) << 8
                len += e.Buffer(3) << 16
                start = 4
            End If

            len = 4 * len

            Dim d(len - 1) As Byte
            Array.Copy(e.Buffer, start, d, 0, len)

            ProcessResponse(d)
        Catch ex As Exception

        End Try

        ReadData()
    End Sub

    Private Sub ProcessResponse(data As Byte())
        'process the data received - identify the TL types returned from Telegram, then store / handle each as required
    End Sub
#End Region