server.py

from flask import Flask, request, Response
import jsonpickle, pickle
import platform
import io, os, sys
import pika, redis
import hashlib, requests
import json
from flask_cors import CORS


#connecting to Rabbit and Redis in applciation, localhost if port-forwarding
redisHost = os.getenv("REDIS_HOST") or "localhost"
rabbitMQHost = os.getenv("RABBITMQ_HOST") or "localhost"

print("Connecting to rabbitmq({}) and redis({})".format(rabbitMQHost,redisHost))

connection = pika.BlockingConnection(pika.ConnectionParameters(host=rabbitMQHost))
channel = connection.channel()
channel.queue_declare(queue='worker_queue', durable=True)

#connecting to data
trackingNumtoInfo = redis.Redis(host=redisHost, db=1)

#initializing flask application
app = Flask(__name__)
CORS(app)

@app.route('/track/<tracking_number>', methods=['GET'])
def track(tracking_number):
	r=request
	#debug case
	if (str(tracking_number)=="123"):
		response_debug={'server':'success'}
		response_pickled=jsonpickle.encode(response_debug)
		return Response(response=response_pickled, status=200, mimetype="application/json")
	## in this part parse request and send it to a worker node
	try:
		#print(val['data'])
		response={'state':"sending to worker node"}
		responsetoRab={'tracking_num': str(tracking_number)}
	except:
		response={'state':"error sending to worker node"}
		responsetoRab= {'tracking_num':"none"}

	response_pickled=jsonpickle.encode(response)
	response_rabbit_pickled=jsonpickle.encode(responsetoRab)

	channel.basic_publish(exchange='',routing_key='worker_queue', body=response_rabbit_pickled)
	return Response(response=response_pickled, status=200, mimetype="application/json")


@app.route('/getInfoHomepage', methods=['GET'])
def getInfoHomepage():
	r=request
	try:
		response_temp=[]
		for i in trackingNumtoInfo.keys():
			val=trackingNumtoInfo.get(i)
			if val:
				print(val)
				response_temp.append(jsonpickle.decode(val))
		response=json.dumps(response_temp)
		print("Response for getInfo is", response)
	except:
		response={'error':'cannot load page'}
	response_pickled=jsonpickle.encode(response)
	return Response(response=response_pickled, status=200, mimetype="application/json")


@app.route('/update', methods=['GET'])
def update():
	r=request

	try:
		for i in trackingNumtoInfo.keys():
			responsetoRab={'tracking_num': str(jsonpickle.decode(i))}
			response_rabbit_pickled=jsonpickle.encode(responsetoRab)
			channel.basic_publish(exchange='',routing_key='worker_queue', body=response_rabbit_pickled)
		response={'update':'success'}
	except:
		response={'update':'fail'}

	response_pickled=jsonpickle.encode(response)
	res=Response(response=response_pickled, status=200, mimetype="application/json")
	return res
	
app.run(host="0.0.0.0", port=5000)