Hacker School Challenge

HS Challenge

'''This is a Python based socket server which runs on localhost port 4000.
Use /set?somekey=somekeyvalue to store a key pair. Use /get?key=somekey to
retrieve a key's value.'''

import socket
import sys

HOST = ""
PORT = 4000
key_pairs = {}  

def create_socket():    
    #Initialize TCP connection
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    #Allow the port to be reused
    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    print "Socket created."

    #Bind socket to localhost and port
    try:
        s.bind((HOST, PORT))
    except socket.error, msg:
        print "Bind failed. Error code :", str(msg[0]), "Message", msg[1]
        sys.exit()

    #Start listening on socket with handling for 1 clients
    s.listen(1)
    print "Waiting for connection..."

    return s

def accept_connection(s):
    #Keep server alive and open for connections
    while True:
        conn, addr = s.accept()
        print "Database accessed from", addr[0] + ":", str(addr[1])

        #Read data from HTTP request
        data = conn.recv(1024)
        #Separate the GET string from the url
        GET_string = data.split(" ")[1]

        #Check for values within the GET string
        if GET_string == "/":
            conn.send("Use /set? or /get? to interact with the server.")
        elif "set" in GET_string:
            key = set_key_pair(GET_string.lower())
            conn.send("%s is now set to %s" % (key, key_pairs[key]))
            print "%s is now set to %s" % (key, key_pairs[key])
        elif "get" in GET_string:
            key = get_key_pair(GET_string.lower())
            conn.send("%s has a value of %s" % (key, key_pairs[key]))
            print "%s has a value of %s" % (key, key_pairs[key])

        #Close current connection
        conn.close()
        
def set_key_pair(url_string):
    #Split the key pair from the action variable
    key_pair = url_string.split("?")[1]
    #Split the key from the key value
    key = key_pair.split("=")[0]
    key_value = key_pair.split("=")[1]
    #Store the key pair globally
    key_pairs[key] = key_value
    return key

def get_key_pair(url_string):
    #Split the key from the action variable
    key_chunk = url_string.split("?")[1] 
    key = key_chunk.split("=")[1]
    return key.lower()  

'''Not sure how to trigger closing the socket cleanly.'''
def close_socket():
    s.close()
    print "Closing out."

def main():
    the_socket = create_socket()
    connection = accept_connection(the_socket)

if __name__ == "__main__":
    main()