demonstration of Asterisk crash due to ARI Bridge race condition

ari_crash.py

from multiprocessing.pool import Pool
from requests.auth import HTTPBasicAuth
from websocket import create_connection
import functools
import json
import random
import requests
import time
import urllib.parse
import threading

bridges = []
channels = []

auth = HTTPBasicAuth("admin", "peekaboo")


def create_bridges():
    for x in range(4):
        params = urllib.parse.urlencode(
            {
                "type": "mixing,dtmf_events,proxy_media",
                "name": "bridge_{}".format(x),
            }
        )
        url = "http://localhost:8088/ari/bridges?{}".format(params)
        resp = requests.post(url, auth=auth)
        bridges.append(resp.json()["id"])
    print("Bridges created", bridges)


def switch_bridge(id, x):
    bridge = random.choice(bridges)
    params = urllib.parse.urlencode(
        {
            "absorbDTMF": 1,
            "mute": 1,
            "channel": id,
        }
    )
    url = "http://localhost:8088/ari/bridges/{}/addChannel?{}".format(bridge, params)
    requests.post(url, auth=auth)
    # just to show something is happening...
    print(".", end="")
    if x % 80 == 0:
        print()
    return x


def start_race():
    with Pool(processes=10) as pool:
        pool.map(functools.partial(switch_bridge, ",".join(channels)), range(20000))
    print("usually crashes before we get here...")


def listen_ws(ws):
    while True:
        result = json.loads(ws.recv())
        if result["type"] == "StasisStart" and result["args"][0] == "3":
            print("4 calls connected, starting bridge switching in 3 seconds...")
            time.sleep(3)
            race_thread = threading.Thread(target=start_race)
            race_thread.start()


def start():
    ws = create_connection(
        "ws://localhost:8088/ari/events?api_key=admin:peekaboo&app=hello"
    )
    listen_thread = threading.Thread(target=listen_ws, args=(ws,))
    listen_thread.start()

    create_bridges()
    for x in range(4):
        params = urllib.parse.urlencode(
            {
                "endpoint": "PJSIP/localout/sip:127.0.0.1:5060",
                "app": "hello",
                "appArgs": "{}".format(x),
            }
        )
        url = "http://localhost:8088/ari/channels?{}".format(params)
        resp = requests.post(url, auth=HTTPBasicAuth("admin", "peekaboo"))
        resp_json = resp.json()
        channels.append(resp_json["id"])
    print("calls originated")


if __name__ == "__main__":
    start()