How To Work With Tcp Sockets In Python

By Author: Appdeveloper
Total Articles: 438
Comment this article

A network/internet socket is an end-point of interposing communication across a computer network. In Python web development, the library has a module called socket which offers a low-level networking interface, it’s common across various app development programming languages since it uses OS-level system calls. When you create a socket, use a function called a socket. It accepts family, type, and prototype arguments. Creating a TCP-socket, for the family, you must use a socket.AF_INET or socket.AF_INET6 and for the type you must use socket.SOCK_STREAM.

Example for Python socket
import socket
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
Main methods to create Python socket objects
• bind() – specific for server sockets.
• listen() – specific for server sockets.
• accept() – specific for server sockets.
• connect() – client sockets.
• send() – both server and client sockets.
• recv() – both server and client sockets.
For instance, echo server from documentation
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
...
... s.bind((‘localhost’, 50000))
s.listen(1)
conn, addr = s.accept()
while 1:
data = conn.recv(1024)
if not data:
break
conn.sendall(data)
conn.close()
To create a server socket, bind it to localhost and 50000 port, and start listening for incoming app development connections. To accept an app developers incoming connection call as accept(), this method will block until a new client connects. When it’s happening, will create a new socket and returns it together with the iOS app developers client’s address. Then, an infinite loop reads data from the socket in batches of 1 KB using method recv() till it returns a blank string. Next, it sends all incoming data back using a method called sendall() which inside repeatedly calls send(). Next, to that, it just closes the client’s connection.