sockets - Lua Copas：发送方协程只是停止工作

Question

我在 Lua 5.2 中使用最新的 Copas 时遇到问题。我编写了一个简单的脚本（见下文），它创建了两个服务器套接字：“RX”和“TX”。“RX”侦听来自连接客户端的消息，“TX”将这些消息传输到连接到“TX”的客户端。

问题是：一开始，服务器启动后，一切正常。但是在一定数量的消息之后，“TX”服务器循环不再执行，不再传输消息。没有错误信息，什么都没有。它只是停止工作。

我用 Copas 错了吗？问题是什么？

这是（简化的）代码：

local copas    = require("copas")
local socket   = require("socket")
local pl_class = require("pl.class")


-- Connection between a server and a client
pl_class.ClientConnection()

function ClientConnection:_init(connectionName, socketToClient)
    self.connectionName       = connectionName
    self.socketToClient       = socketToClient
    self.queueMessagesToSend  = {}
end

function ClientConnection:popMessageToSend()
    return table.remove(self.queueMessagesToSend, 1);
end

function ClientConnection:pushMessageToSend(theMessage)
    table.insert(self.queueMessagesToSend, theMessage)
end


-- Server base class
pl_class.Server()

function Server:_init(serverName, serverPort)
    self.serverName            = serverName
    self.serverPort            = serverPort
    self.connectedClients      = {}
end

function Server:initServing()
    local server = socket.bind("*", self.serverPort)
    print("[" .. self.serverName .. "] Waiting for client connections on port " .. self.serverPort .. "...")
    copas.addserver(server, function(c) return self.connectionHandler(copas.wrap(c), c:getpeername()) end )
end


-- Class for send-only servers
pl_class.ServerSendOnly(Server)

function ServerSendOnly:_init(serverName, serverPort)
    self:super(serverName, serverPort)

    self.connectionHandler = function (socketToClient, clientHost, clientPort)
        local connObject = ClientConnection(clientHost..":"..tostring(clientPort), socketToClient)
        self.connectedClients[connObject.connectionName] = connObject
        while true do
            local currMessage = connObject:popMessageToSend()
            if currMessage then
                copas.send(connObject.socketToClient, currMessage)
            end
            copas.sleep(0.01)
        end
        self.connectedClients[connObject.connectionName] = nil
    end

end

function ServerSendOnly:broadcastMessage(currMessage)
    for connName,connObject in pairs(self.connectedClients) do
        connObject:pushMessageToSend(currMessage .. "\r\n")
    end
end


-- Class for receive-only servers
pl_class.ServerReceiveOnly(Server)

function ServerReceiveOnly:_init(serverName, serverPort)
    self:super(serverName, serverPort)
    self.queueMessagesReceived = {}

    self.connectionHandler = function (socketToClient, clientHost, clientPort)
        local connObject = ClientConnection(clientHost..":"..tostring(clientPort), socketToClient)
        self.connectedClients[connObject.connectionName] = connObject
        while true do
            local currDataReceived = copas.receive(connObject.socketToClient)
            if currDataReceived ~= nil then
                local currInfo = {client=connObject.connectionName, data=currDataReceived}
                table.insert(self.queueMessagesReceived, currInfo)
            end
        end
        self.connectedClients[connObject.connectionName] = nil
    end

end

function ServerReceiveOnly:popMessageReceived()
    return table.remove(self.queueMessagesReceived, 1);
end


-- Setup servers
local serverSend    = ServerSendOnly("ServerTX", 2345)
local serverReceive = ServerReceiveOnly("ServerRX", 1234)

serverSend:initServing()
serverReceive:initServing()


-- Main loop: Pass messages which arrived at the RX server to the clients
-- connected to the TX servers ("RX" and "TX" are used from the server's POV)
while true do
    copas.step()

    local currMessage = serverReceive:popMessageReceived()
    if currMessage then
        print("[" .. serverReceive.serverName .. "] MESSAGE RECEIVED FROM '" .. currMessage.client .."': " .. currMessage.data)
        serverSend:broadcastMessage(currMessage.data)
    end
end