How to add logging to a file with timestamps to a Python TCP Server for Raspberry Pi

Question

I am kinda stuck for my project & I desperately need help. I need a simple TCP server python code that has features like logging & time stamp which I could use for my Raspberry Pi. Its for my Final Year Project.

I've looked at some examples, but as I don't have much experience in writing my own scripts/codes, I'm not very sure how to go about doing this. I would appreciate if someone could guide me in the right direction with explanation and some examples if possible.

I am using HERCULES SETUP UTILITY , which acts as my TCP client, while my visual studio python code acts as a SERVER. My SERVER can receive the data which is sent by the client by now , I just can't seem to add in a logging file which can save the sent data into text file.Can someone please show me some examples or referance please? Your help would mean alot. This is my code so far :

from socket import *
import thread

BUFF = 1024 # buffer size
HOST = '172.16.166.206'# IP address of host
PORT = 1234 # Port number for client & server to recieve data
def response(key):
    return 'Sent by client'

def handler(clientsock,addr):
    while 1:
        data = clientsock.recv(BUFF) # receive data(buffer).
        print 'data:' + repr(data)   #Server to recieve data sent by client.
        if not data: break           #If connection is closed by client, server will        break and stop recieving data.
        print 'sent:' + repr(response('')) # respond by saying "Sent By Client". 



if __name__=='__main__':
    ADDR = (HOST, PORT) #Define Addr
    serversock = socket(AF_INET, SOCK_STREAM) 
    serversock.bind(ADDR) #Binds the ServerSocket to a specific address (IP address and     port number)
    serversock.listen(0)
    while 1:
        print 'waiting for connection...'
        clientsock, addr = serversock.accept()
        print '...connected from:', addr #show its connected to which addr
        thread.start_new_thread(handler, (clientsock, addr ))

Answer 1

To add logging to a file with timestamps, you could use logging module:

import logging

logging.basicConfig(level=logging.INFO, 
                    filename='myserver.log', # log to this file
                    format='%(asctime)s %(message)s') # include timestamp
logging.info("some message")

If you run the code; you should see in myserver.log (+/- your timezone and current time):

2013-12-24 09:20:17,739 some message

Here's a complete example of TCP server that prepends each received line from a client with "Sent by Client: " phrase and sends it back:

#!/usr/bin/env python
import logging
import sys
from SocketServer import ThreadingTCPServer, StreamRequestHandler

info = logging.getLogger(__name__).info

class EchoLineHandler(StreamRequestHandler):
    def handle(self):
        info("handling request from %s", self.client_address)
        # prepend each line (b'\n') and send it back
        for line in self.rfile:
            self.wfile.write(b"Sent by Client: ") # assume ascii-based encoding
            self.wfile.write(line)
        info("done %s", self.client_address)

def test(ServerClass=ThreadingTCPServer, HandlerClass=EchoLineHandler):
    # configure logging
    logging.basicConfig(level=logging.INFO,
                        filename='server.log', # log to this file
                        format='%(asctime)s %(message)s') # include timestamp

    # parse command line arguments
    host, port = 'localhost', 8826
    if len(sys.argv) > 1:
        host_, separator, port_ = sys.argv[1].rpartition(":")
        port = int(port_)
        if separator: # if ":" in sys.argv[1]
            host = host_ # accept any host, including empty

    # listen for connections
    server = ServerClass((host, port), HandlerClass)
    info("Serving on %s port %s", *server.server_address)
    try:
        server.serve_forever()
    finally:
        info("quit.")

if __name__=="__main__":
    test()

To run the server if the code is save in echo_line_server.py:

$ python -mecho_line_server localhost:8826 & tail -F server.log
2013-12-24 17:09:38,089 Serving on 127.0.0.1 port 8826

To run a client:

$ echo abc | nc localhost 8826
Sent by Client: abc