ESP8266 NodeMCU Lua將「套接字客戶端」連接到「Python服務器」連接不可能

Question

我試圖將NodeMCU套接字客戶端程序連接到Python服務器程序，但我無法建立連接。

我測試了一個簡單的Python客戶端服務器代碼，它運行良好。

Python的服務器代碼

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客戶機代碼（與此我測試上面的代碼）

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  

輸出服務器側是

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

NodeMCU代碼

--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) 

但是當我運行NodeMCU時，Python服務器中沒有響應。

在ESPlorer控制檯輸出看起來像

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 

難道我做錯了什麼或在這裏失去了一些步驟？

您的指導表示讚賞。

Answer 1

當我第二次重新訪問它時，它終於點擊了。我一定是第一次掃描你的Lua代碼太快了。

您需要設置所有事件處理程序（srv:on）之前您建立連接。否則它們可能不會發射 - 取決於建立連接的速度。

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是錯誤的，但它已經fixed in the dev branch。