Socket Programming w/ Multithreading

Socket Programming-> 클라이언트/서버 연결해주는 프로그램.

클라리언트는 메세지를 전달하고 받는 주체

서버는 클라이언트가 보내는 데이터로 작업하는 리스너(수동적인 주체)

Thread -> 기존 프로세스보다 좀더 가볍게 메모리 오버헤드를 사용하는 분할된 프로세스

Multi-threading -> 여러개 스레드를 "하나의 프로세스"에서 동시에 실행시키는 작업(프로세스)

Multi-threading Socket Programming -> 소켓연결을 멀티스레딩으로 구현해놓은 프로그램

 

Multi-threading Modules :파이썬은_thread 과 threading 모듈로 멀티스레딩구현함

(동기화와 스레드LOCK 가능함)

*스레드 락 

- 락 : lock.acquire()

- 언락 : lock.release()

*스레드 생성 : thread.start_new_thread

from _thread import *
import threading

lock = threading.Lock()

# Server

# import socket programming library 
import socket 

# import thread module 
from _thread import *
import threading 

print_lock = threading.Lock() 

# thread function 
def threaded(c): 
	while True: 

		# data received from client 
		data = c.recv(1024) 
		if not data: 
			print('Bye') 
			
			# lock released on exit 
			print_lock.release() 
			break

		# reverse the given string from client 
		data = data[::-1] 

		# send back reversed string to client 
		c.send(data) 

	# connection closed 
	c.close() 


def Main(): 
	host = "" 

	# reverse a port on your computer 
	# in our case it is 12345 but it 
	# can be anything 
	port = 12345
	s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) 
	s.bind((host, port)) 
	print("socket binded to port", port) 

	# put the socket into listening mode 
	s.listen(5) 
	print("socket is listening") 

	# a forever loop until client wants to exit 
	while True: 

		# establish connection with client 
		c, addr = s.accept() 

		# lock acquired by client 
		print_lock.acquire() 
		print('Connected to :', addr[0], ':', addr[1]) 

		# Start a new thread and return its identifier 
		start_new_thread(threaded, (c,)) 
	s.close() 


if __name__ == '__main__': 
	Main() 

 

# Client

# Import socket module 
import socket 


def Main(): 
	# local host IP '127.0.0.1' 
	host = '127.0.0.1'

	# Define the port on which you want to connect 
	port = 12345

	s = socket.socket(socket.AF_INET,socket.SOCK_STREAM) 

	# connect to server on local computer 
	s.connect((host,port)) 

	# message you send to server 
	message = "shaurya says geeksforgeeks"
	while True: 

		# message sent to server 
		s.send(message.encode('ascii')) 

		# messaga received from server 
		data = s.recv(1024) 

		# print the received message 
		# here it would be a reverse of sent message 
		print('Received from the server :',str(data.decode('ascii'))) 

		# ask the client whether he wants to continue 
		ans = input('\nDo you want to continue(y/n) :') 
		if ans == 'y': 
			continue
		else: 
			break
	# close the connection 
	s.close() 

if __name__ == '__main__': 
	Main() 

https://www.google.com/amp/s/www.geeksforgeeks.org/socket-programming-multi-threading-python/amp/