Asynchronous service with tornado

Asynchronous service with tornado.ipynb

main.py

import time
import pandas as pd
from tornado import ioloop, web, httpserver, httpclient

class LongQueryHandler(web.RequestHandler):
    def get(self):
        response = [pd.Timestamp.utcnow().time().isoformat()]     # Catch the current time.
        time.sleep(0.1)                                           # Wait 0.1 second.
        response.append(pd.Timestamp.utcnow().time().isoformat()) # Catch the time again.
        self.write(pd.json.dumps(response))                       # Returns a JSON.

class SynchronousHandler(web.RequestHandler):
    def get(self):
        client = httpclient.HTTPClient()
        output = [pd.Timestamp.utcnow().time().isoformat()]
        response = client.fetch('http://localhost:8888/longquery')
        output += pd.json.loads(response.body)
        output.append(pd.Timestamp.utcnow().time().isoformat())
        self.write(pd.json.dumps(output))

class AsynchronousHandler(web.RequestHandler):
    @web.asynchronous
    def get(self):
        client = httpclient.AsyncHTTPClient()
        self.output = [pd.Timestamp.utcnow().time().isoformat()]
        response = client.fetch('http://localhost:8888/longquery',self.on_response)
    def on_response(self, response):
        self.output += pd.json.loads(response.body)
        self.output.append(pd.Timestamp.utcnow().time().isoformat())
        self.write(pd.json.dumps(self.output))
        self.finish()

app = web.Application([
    ("/longquery", LongQueryHandler),
    ("/synchronous", SynchronousHandler),
    ("/asynchronous", AsynchronousHandler),
    ])

server = httpserver.HTTPServer(app)
server.bind(8888)
server.start(100)  # forks one process per cpu
ioloop.IOLoop.current().start()