dus-flughafen-foo/server-web.py

from seleniumwire import webdriver  # Import from seleniumwire
from seleniumwire.utils import decode
from time import sleep
from flask import Flask as f
from flask import Response
from dateutil import parser
from datetime import datetime, timedelta, timezone
import json
import re
import asyncio
import logging
import threading
import os

log = logging.getLogger('werkzeug')
log.setLevel(logging.ERROR)
log.disabled = True



# Create a new instance of the Chrome driver
valuestore = {}
datestore = {}
lastUpdate = datetime.now(timezone.utc)

app = f("web")
#app.logger.disabled = True
h2 = timedelta(hours=2)

def interceptor(request, response):  # A response interceptor takes two args
    global lastUpdate
    if 'ws-travis.dus.com/socket.io/?EIO=3&transport=polling' in request.url :
        body = decode(response.body, response.headers.get('Content-Encoding', 'identity'))
        x = re.split("\d\d\d:\d\d\/dus,", body.decode("utf-8"))
        lastUpdate = datetime.now(timezone.utc)
        for i in [i for i in x if i]:
            try:
                j = json.loads(i)
                handleJson(j)
            except ValueError:
                if i.find("online-level") > 0:
                    #print ("Fixed: ", i)
                    j = json.loads(i[:i.rfind(']') + 1])
                    handleJson(j)
                #else:
                    #print ("Err: ", i)

# StackOverflow
def killChildren(driver):
    print('Quitting session: ',  driver.session_id)
    driver.quit()
    try:
        pid = True
        while pid:
            pid = os.waitpid(-1, os.WNOHANG)
            print("Reaped child: ", str(pid))

            try:
                if pid[0] == 0:
                    pid = False
            except:
                pass

    except ChildProcessError:
        pass

def idIsRecent(id):
    return id in valuestore and datetime.now(timezone.utc) - parser.parse(datestore[id]) < timedelta(seconds=30)

def handleJson(jsonObj):
    if isinstance(jsonObj, list):
        if 'online-level' in jsonObj:
            #type = jsonObj[1]["LevelValues"][0]["Type"]
            value = jsonObj[1]["LevelValues"][0]["Values"][0]
            NmtId = jsonObj[1]["NmtId"]
            time = jsonObj[1]["Time"]
            valuestore[NmtId] = value
            datestore[NmtId] = time

# Gibt den letzten bekannten Wert fuer die NMTID zurueck
@app.route('/nmt/<int:id>')
def nmtid(id):
    if idIsRecent(id):
        return format( valuestore[id], '.1f')
    else:
        return "E_NA" # Entweder out of date oder nicht existent

# Gibt eine Liste mit verfuegbaren ids zurueck
@app.route('/ids')
def ids():
    l = filter(idIsRecent,list(valuestore.keys()))
    return ','.join(map(str,list(l)))

def createDriver(id):
    options = webdriver.ChromeOptions()
    options.add_argument('--headless')
    options.add_argument("--incognito")
    options.add_argument("--nogpu")
    options.add_argument("--disable-gpu")
    options.add_argument("--window-size=1280,1280")
    options.add_argument("--no-sandbox")
    options.add_argument("--enable-javascript")
    options.add_argument('--disable-dev-shm-usage')
    data_dir = "--user-data-dir=/tmp/" + str(id)
    options.add_argument(data_dir)
    
    try:
        driver = webdriver.Chrome(options=options)
    except:
        print ("creation failed badly, waiting 10s and retrying")
        sleep(10)
        driver = createDriver(id)
        return driver
    driver.response_interceptor = interceptor
    return driver

def startRequest(driver):
    try:
        driver.get('https://dus-travis.dus.com/')
    except:
        print ("GET failed. Main loop will handle that")
        pass

def assertWorking():
    return lastaccess > datetime.now(timezone.utc) - timedelta(seconds=10)

if __name__ == '__main__':

    print("Starting the Server")

    # start flask server
    threading.Thread(target=lambda: app.run(host='0.0.0.0', port=80, debug=False, use_reloader=False)).start()
    
    # wait time to restart will be dynamically adapted, 
    # if unexpected things happen in chrome or the real world
    restartWait = timedelta(hours=10)

    # setup webdriver
    d0 = createDriver(0)

    # start initial driver
    startRequest(d0)
    lastaccess = datetime.now(timezone.utc)
    
    # loop and restart with restartWait Interval
    while True:
        sleep(30)
        if datetime.now(timezone.utc) > lastaccess + restartWait:
            d1 = createDriver(1)
            startRequest(d1)
            print ("New Failover Driver started, waiting 10 seconds ...")
            sleep(10)
            killChildren(d0)
            del d0
            print ("Original driver deleted")
            d0 = createDriver(0)
            startRequest(d0)
            print ("Recreating original driver and waiting 10 seconds ...")
            sleep(10)
            killChildren(d1)
            del d1
            print ("Failover Driver deleted")
            lastaccess = datetime.now(timezone.utc)

        l = filter(idIsRecent,list(valuestore.keys()))
        if len(list(l)) < 1 and not assertWorking():
            restartWait = timedelta(minutes=3)
            print ("Something stupid happened, setting interval to 3m")
        else:
            if restartWait < timedelta(hours=1):
                restartWait = timedelta(hours=10)
                print ("Something stupid normalized, resetting interval to 10h")