Socket communication using socketserver with python now

Purpose

With reference to the following, it is a memorandum when TCP / UDP socket communication with python, although it feels more like now.

socketserver --- Network server framework

About socket communication

Socket The Internet uses a communication protocol called TCP / IP, but in order to use that TCP / IP programmatically, a special doorway connecting the world of programs and the world of TCP / IP is required. The gateway is the socket, which is a major feature of TCP / IP programming. Source: http://research.nii.ac.jp/~ichiro/syspro98/socket.html

TCP socket communication

The alphabet sent by the client side to the server side is capitalized by the server side and returned to the client.

receiver.py

import socketserver

class MyTCPHandler(socketserver.BaseRequestHandler):
    def handle(self):
        self.data = self.request.recv(1024).strip()
        print("{} wrote:".format(self.client_address[0]))
        print(self.data)
        self.request.sendall(self.data.upper())

if __name__ == "__main__":
    HOST, PORT = "localhost", 9999

    with socketserver.TCPServer((HOST, PORT), MyTCPHandler) as server:
        server.serve_forever()

sender.py

import socket
import sys

HOST, PORT = "localhost", 9999
data = " ".join(sys.argv[1:])

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
    sock.connect((HOST, PORT))
    sock.sendall(bytes(data + "\n", "utf-8"))
    received = str(sock.recv(1024), "utf-8")

print("Sent:     {}".format(data))
print("Received: {}".format(received))

Execute

$ python receive.py

$ python sender.py "hello world"
Sent:     hello world
Received: HELLO WORLD

UDP socket communication

Unlike TCP, UDP has no connection and keeps sending data.

receiver.py

import socketserver

class MyUDPHandler(socketserver.BaseRequestHandler):

    def handle(self):
        data = self.request[0].strip()
        socket = self.request[1]
        print("{} wrote:".format(self.client_address[0]))
        print(data)
        socket.sendto(data.upper(), self.client_address)

if __name__ == "__main__":
    HOST, PORT = "localhost", 9999
    with socketserver.UDPServer((HOST, PORT), MyUDPHandler) as server:
        server.serve_forever()

sender.py

import socketserver

class MyUDPHandler(socketserver.BaseRequestHandler):

    def handle(self):
        data = self.request[0].strip()
        socket = self.request[1]
        print("{} wrote:".format(self.client_address[0]))
        print(data)
        socket.sendto(data.upper(), self.client_address)

if __name__ == "__main__":
    HOST, PORT = "localhost", 9999
    with socketserver.UDPServer((HOST, PORT), MyUDPHandler) as server:
        server.serve_forever()

Execute

$ python receive_udp.py

$ python sender_udp.py "hello world. udp."
Sent:     hello world. udp.
Received: HELLO WORLD. UDP.

Remarks

If the communication data is large, there will be a difference in execution time and handling of missing data, but it is omitted because it is a trial. Learn more about how UDP differs from TCP

Socket communication

reference

socketserver --- Network server framework Communication processing by Python cpython/Lib/socketserver.py Let's learn the basics of socket communication that I knew Matsumoto Naoden Programming Okite 16th Network Programming (Socket Edition) Socket communication