Python Klein - Non Blocking Api

Need help with Klein API for Non-blocking. This is a simple test app: # -*- coding: utf-8 -*- import datetime import json import time from klein import Klein app = Klein() async

Solution 1:

So, the problem is your delay function - its a blocking function, because python's time.sleep - is blocking. More on this you can read here.

You should use task.deferLater which you can think of as the non-blocking sleep function of Twisted framework, similar to asyncio.sleep()

# app.pyimport datetime
import json

import treq
from klein import Klein
from twisted.internet import task, reactor

app = Klein()

asyncdefdelay1(secs):
    await task.deferLater(reactor, secs)
    return"Works"defdelay2(secs):
    return task.deferLater(reactor, secs, lambda: "Works")

@app.route('/', branch=True)asyncdefmain(request):
    some_data = await delay1(5)  # or some_data = await delay2(5) return json.dumps([{
        "status": "200",
        "time": datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
        "data": some_data
    }])

defsend_requests():
    for i inrange(2):
        print("request", datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S"))
        d = treq.get('http://localhost:8080')
        d.addCallback(treq.content)
        d.addCallback(lambda x: print("response", x.decode()))

# send 2 concurrent requests every 10 seconds to test the code
repeating = task.LoopingCall(send_requests)
repeating.start(10, now=False)

app.run("localhost", 8080)

to run the code

$ pip3 install treq klein
$ python3 app.py

wait 10 seconds and the output should be

2019-10-2117:17:11-0400 [-] request 2019-10-2117:17:112019-10-2117:17:11-0400 [-] request 2019-10-2117:17:112019-10-2117:17:16-0400 [-] "127.0.0.1" - - [21/Oct/2019:21:17:16 +0000] "GET / HTTP/1.1"20067"-""-"2019-10-2117:17:16-0400 [-] "127.0.0.1" - - [21/Oct/2019:21:17:16 +0000] "GET / HTTP/1.1"20067"-""-"2019-10-2117:17:16-0400 [-] response [{"status": "200", "time": "2019-10-21 17:17:16", "data": "Works"}]
2019-10-2117:17:16-0400 [-] response [{"status": "200", "time": "2019-10-21 17:17:16", "data": "Works"}]