ESP8266 NodeMCU Lua将“套接字客户端”连接到“Python服务器”连接不可能

Question

我试图将NodeMCU套接字客户端程序连接到Python服务器程序，但我无法建立连接。

我测试了一个简单的Python客户端服务器代码，它运行良好。

Python的服务器代码

import socket    # Import socket module 

s = socket.socket()   # Create a socket object 
host = socket.gethostname() # Get local machine name 
port = 12345    # Reserve a port for your service. 
s.bind((host, port))  # Bind to the port 

s.listen(5)     # Now wait for client connection. 
while True: 
    c, addr = s.accept()  # Establish connection with client. 
    print 'Got connection from', addr 
    print c.recv(1024) 
    c.send('Thank you for connecting') 
    c.close()    # Close the connection 

Python客户机代码（与此我测试上面的代码）

import socket    # Import socket module 

s = socket.socket()   # Create a socket object 
host = socket.gethostname() # Get local machine name 
port = 12345    # Reserve a port for your service. 

s.connect((host, port))  
s.send('Hi i am aslam') 
print s.recv(1024) 
s.close      # Close the socket when done  

输出服务器侧是

Got connection from ('192.168.99.1', 65385) 
Hi i am aslam 

NodeMCU代码

--set wifi as station 
print("Setting up WIFI...") 
wifi.setmode(wifi.STATION) 
--modify according your wireless router settings 
wifi.sta.config("xxx", "xxx") 
wifi.sta.connect() 

function postThingSpeak() 
    print("hi") 
    srv = net.createConnection(net.TCP, 0) 
    srv:on("receive", function(sck, c) print(c) end) 
    srv:connect(12345, "192.168.0.104") 
    srv:on("connection", function(sck, c) 
    print("Wait for connection before sending.") 
    sck:send("hi how r u") 
    end) 
end 

tmr.alarm(1, 1000, 1, function() 
    if wifi.sta.getip() == nil then 
    print("Waiting for IP address...") 
    else 
    tmr.stop(1) 
    print("WiFi connection established, IP address: " .. wifi.sta.getip()) 
    print("You have 3 seconds to abort") 
    print("Waiting...") 
    tmr.alarm(0, 3000, 0, postThingSpeak) 
    end 
end) 

但是当我运行NodeMCU时，Python服务器中没有响应。

在ESPlorer控制台输出看起来像

Waiting for IP address... 
Waiting for IP address... 
Waiting for IP address... 
Waiting for IP address... 
Waiting for IP address... 
Waiting for IP address... 
WiFi connection established, IP address: 192.168.0.103 
You have 3 seconds to abort 
Waiting... 
hi 

难道我做错了什么或在这里失去了一些步骤？

您的指导表示赞赏。

Answer 1

当我第二次重新访问它时，它终于点击了。我一定是第一次扫描你的Lua代码太快了。

您需要设置所有事件处理程序（srv:on）之前您建立连接。否则它们可能不会发射 - 取决于建立连接的速度。

srv = net.createConnection(net.TCP, 0) 
srv:on("receive", function(sck, c) print(c) end) 
srv:on("connection", function(sck) 
    print("Wait for connection before sending.") 
    sck:send("hi how r u") 
end) 
srv:connect(12345,"192.168.0.104") 

的example in our API documentation是错误的，但它已经fixed in the dev branch。