server.py

from __future__ import print_function

from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
from SocketServer import ThreadingMixIn
import threading
import json
import random
import re
import socket
import Pyro4
from src.Worker import Worker


workers = []

# Inspired by:
#   https://mafayyaz.wordpress.com/2013/02/08/writing-simple-http-server-in-python-with-rest-and-json/
class HTTPRequestHandler(BaseHTTPRequestHandler):
    def initialize(self):
        self.name_server = Pyro4.locateNS("newyork")
        self.workers = []
        self.update_workers()

    def do_GET(self):
        if 'workers' not in self.__dict__:
            self.initialize()

        if None != re.search('/sparrow/status', self.path):
            # API request
            self.update_workers()

            statuses = {}
            for worker in self.workers:
                statuses[worker.get_name()] = worker.find_load()

            # statuses = {
            #     "worker1" : random.randint(0,5),
            #     "worker2" : random.randint(0,5)
            # }

            self.send_response(200)
            self.send_header('Content-Type', 'application/json')
            self.end_headers()
            self.wfile.write(json.dumps(statuses))
        elif None != re.search('/sparrow', self.path):
            # Send back webpage
            with open('web/index.html', 'r') as html_file:
                html = html_file.read()

            self.send_response(200)
            self.send_header("Content-type", "text/html")
            self.send_header("Content-Length", str(len(html)))
            self.end_headers()
            self.wfile.write(html)
        elif None != re.search('web', self.path):
            # Resource request
            resource = self.path.split('/')[-1]
            with open("web/" + resource, 'r') as resource_file:
                res = resource_file.read()

            self.send_response(200)

            if "css" in self.path:
                type = "text/css"
            else:
                type = "text/html"

            self.send_header("Content-type", type)
            self.send_header("Content-Length", str(len(res)))
            self.end_headers()
            self.wfile.write(res)
        else:
            # Invalid request
            self.send_response(403)
            self.send_header('Content-Type', 'application/json')
            self.end_headers()

    def update_workers(self):
        # List all sparrow workers (i.e. sparrow.worker.arizona)
        worker_dict = self.name_server.list('sparrow.worker')

        for key in worker_dict:
            worker = Pyro4.Proxy(worker_dict[key])
            if worker not in self.workers:
                self.workers.append(worker)

        print(self.workers)


class ThreadedHTTPServer(ThreadingMixIn, HTTPServer):
    allow_reuse_address = True

    def shutdown(self):
        self.socket.close()
        HTTPServer.shutdown(self)


class SimpleHttpServer():
    def __init__(self, ip, port):
        self.server = ThreadedHTTPServer((ip, port), HTTPRequestHandler)


if __name__ == '__main__':
    HOST = socket.gethostname()
    PORT = 8901

    server = SimpleHttpServer(HOST, PORT)
    print('Starting server at %s:%d' % (HOST, PORT))
    server.server.serve_forever()