如何使用 sockets 同时从客户端向服务器发送 2 个变量 [Python]

Question

Client.py

import socket

HOST = '127.0.0.1'
PORT = 65432

ALPHABET = 'abcdefghijklmnopqrstuvwxyz0123456789.'
message  = 'This message is encrypted using Caesar cipher'        

def encryptstr(message,key):
    #creating a list for new letters
    newletters = []
    #loop to assign new letter value
    for letter in message:
        uppercase = letter.isupper()
        letter = letter.lower()
    #checking if the letter is upper or lower
        if letter in ALPHABET:
            index = ALPHABET.find(letter)
            newindex = (index + key) % len(ALPHABET)
            letter = ALPHABET[newindex]
            if uppercase:
                letter = letter.upper()
        newletters.append(letter)
    #joining the list
    return ''.join(newletters)

def findkey():
    return 10

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
  s.connect((HOST, PORT))
  test = encryptstr(message, findkey())
  s.sendall(test.encode()) # How to send key of 10 and Message?
  data = s.recv(1024)
  print('Received', data.decode())

Server.py

import socket

HOST = '127.0.0.1'
PORT = 65432

ALPHABET = 'abcdefghijklmnopqrstuvwxyz0123456789.'

def decryptstr(message,key):
    #creating a list for new letters
    newletters = []
    #loop to assign new letter value
    for letter in message:
        uppercase = letter.isupper()
        letter = letter.lower()
    #checking if the letter is upper or lower
        if letter in ALPHABET:
            index = ALPHABET.find(letter)
            newindex = (index - key) % len(ALPHABET)
            letter = ALPHABET[newindex]
            if uppercase:
                letter = letter.upper()
        newletters.append(letter)
    #joining the list
    return ''.join(newletters)
  
def findkey():
  return 10

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
  s.bind((HOST, PORT))
  s.listen()
  conn, addr = s.accept()
  with conn:
    print('Connected by', addr)
    while True:
      data = conn.recv(1024)
      message = str(data.decode())
      test = decryptstr(message, findkey())
      print(test)
      if not data:
        break
      conn.sendall(data)

What I am trying to do with this current code is from the server. I wish to send the variable of "10" to the client. From the client to the server, I would like to send back two variables, one being "10" and the other being the encrypted message. After both are sent, I would like the server to decrypt the message and print it on the screen.

You may be wondering why I would send the ten back and forth, and this is because I will be incorporating this Diffie-Hellman Example with the def findkeys() , Thank you for your time!

Answer 1

client...

sock.send(b'10'+encrypted_message)

server

msg = sock.recv(1024)
code = msg[:2]
encrypted_payload = msg[2:]

Is this what you mean?

Answer 2

You can send that var in json instead of single var it could help you to send more then 1 data at same time