TCP_Server_py

# listen.py

from threading import Thread
import socket
import time
import sys
VERBOSE = False # Enables/Disables printing of debug messages
IP_PORT = 22000 # the port that tinkerboard listens to 
TIME_INTERVAL = 10 # sec

def debug(text):
    if VERBOSE:
        print ("Debug:---", text)

# ---------------------- class SocketHandler ------------------------
class SocketHandler(Thread):
    def __init__(self, conn):
        Thread.__init__(self)
        self.conn = conn

    def run(self):
        global isConnected
        debug("SocketHandler started")
        while True:
            cmd = ""
            try:
                debug("Calling blocking conn.recv()")
                cmd = self.conn.recv(1024)
            except:
                debug("exception in conn.recv()") 
                # happens when connection is reset from the peer
                break
            debug("Received cmd: " + cmd + " len: " + str(len(cmd)))
            if len(cmd) == 0:
                break
            self.executeCommand(cmd)
        conn.close()
        print ("Client disconnected. Waiting for next client...")
        isConnected = False
        debug("SocketHandler terminated")

    def executeCommand(self, cmd):
        print(cmd)
        if cmd == "getWeight" : # removed the trailing "\0"
            print("commandReceived: " + "getWeight")
            

    def reply(self, msg):
        print("Sent message to all: " + msg)
        self.conn.sendall(msg + "\0")
# ----------------- End of SocketHandler -----------------------

# setup()
serverSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# close port when process exits:
serverSocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) 
debug("Socket created")
HOSTNAME = "" # Symbolic name meaning all available interfaces
try:
    serverSocket.bind((HOSTNAME, IP_PORT))
except socket.error as msg:
    print ("Bind failed", msg[0], msg[1])
    sys.exit()
serverSocket.listen(10) # 10 clients?

print ("Waiting for a connecting client...")
isConnected = False
while True:
    debug("Calling blocking accept()...")
    conn, addr = serverSocket.accept()
    print ("Connected with client at " + addr[0])
    print(addr)
    isConnected = True
    socketHandler = SocketHandler(conn)
    # necessary to terminate it at program termination:
    socketHandler.setDaemon(True)  
    socketHandler.start()
    t = 0
    while isConnected: # check connection status every TIME_INTERVAL secs
        debug ("Server connected at" + str(t) + "s")
        socketHandler.reply("This is a message from the server") # broadcast to all
        time.sleep(10)
        t += TIME_INTERVAL