Python, socket, freezing the console before departure

I have two codes server and client. When sending an image from the client to the server, everything goes fine, but later I want to send a message to the client from the server and before sending it, the console simply freezes on both the client and the server

The code for the server:

import socket

server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(("127.0.0.1", 5005))
server.listen()

client, addr = server.accept()
id = 4

print("w")
file = open("out.png", mode="wb")
data = client.recv(4096)
while data:
    file.write(data)
    data = client.recv(4096)
file.close()

print("ww")
client.sendall(str(id).encode('utf8'))
server.close()

The code for the client:

import socket
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect(("127.0.0.1", 5005))

file = open("tstop/abdul.jpg", mode="rb")
data = file.read(4096)
print("up")
while data:
    client.send(data)
    data = file.read(4096)
file.close()
print("down")

data = client.recv(2048)
print ("Received response:" + str(data.decode('utf8')))
client.close()

I used the print to understand at what point I have the code hanging I recently started studying the socket library

Solution

You need to somehow inform the server that no more data will be sent.

There are several different approaches to this, the simplest of which is to do:

client.shutdown(socket.SHUT_WR)

...on the client side once your while data: loop terminates

You can simplify all of your code like this:

# server

import socket

CHUNK = 4096

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as server:
    server.bind(("0.0.0.0", 5006))
    server.listen()
    try:
        client, _ = server.accept()

        with open("out.png", mode="wb") as file:
            while data := client.recv(CHUNK):
                file.write(data)

        client.sendall(b"4")
    finally:
        client.close()

# client

import socket

CHUNK = 4096

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as client:
    client.connect(("127.0.0.1", 5006))

    with open("tstop/abdul.jpg", mode="rb") as file:
        while data := file.read(CHUNK):
            client.send(data)
        client.shutdown(socket.SHUT_WR)

    data = client.recv(CHUNK)
    print ("Received response: " + data.decode())

Thus, out.png will be a replica of tstop/abdul.jpg and the client code will output: