three_nodes.py

#!/usr/bin/env python3
import logging
import random
import requests
import sys
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer


SERVERS = [
    '127.0.0.1:8081',
    '127.0.0.2:8082',
    '127.0.0.3:8083',
]


class myHandler(BaseHTTPRequestHandler):

    def do_GET(self):
        logging.warning(self.server.server_address)
        self.send_response(200)
        self.send_header('Content-type', 'text/html')
        self.end_headers()
        if self.path == '/':
            choices = make_a_choice(self)
        if self.path == '/node':
            choices = random.choice(['yes', 'no'])
        self.wfile.write(choices)
        return


def make_a_choice(host_self):
    choices = {'yes': 0, 'no': 0}
    choices[random.choice(['yes', 'no'])] += 1
    for each_server in SERVERS:
        if each_server != ':'.join(str(ea_item) for ea_item
                                   in host_self.server.server_address):
            logging.warning('requesting {}'.format(each_server))
            choices1 = requests.get('http://{}/node'.format(each_server))
            choices[choices1.text] += 1
        else:
            logging.warning('samve server!')
            logging.warning(host_self.server.server_address)
    return 'yes' if choices['yes'] > choices['no'] else 'no'


def setup_server(host, port):
    server = HTTPServer(('{}'.format(host), int(port)), myHandler)
    logging.warning('Started httpserver on \
        server {} and port {}'.format(host, port))
    server.serve_forever()


if __name__ == '__main__':
    for each_node in SERVERS:
        each_node = each_node.split(':')
        setup_server(each_node[0], each_node[1])

Your task is to build a simple distributed decision system. Think of it as an over complicated magic eight ball that only answers “yes” or “no”. The result is random and each node must be involved in the decision. The system has the following additional requirements:

● There must be three nodes in the system.
● Each node must be involved in the vote.
● Clients communicate with the system via an HTTP GET and expects a response body containing yes or no.
● Any node in the system must be able to handle a client request.
● The system must run on either three separate computers or a single computer for testing.