waitForQuiescence always times out

[dkbarn]

I am having trouble getting the /wait endpoint to behave as expected. No matter how short I set the quiet period, or how long I set the timeout, it always times out. For example, if I set quietPeriodInMs to 1 and timeoutInMs to 120000, it will take 120000 ms and timeout, even when there should be no traffic at all.

To Reproduce

1. Start a browserup server. For me this looks like:
   /opt/browserup-proxy-2.1.2/bin/browserup-proxy --port 30050
2. Add a proxy and start chromedriver using this proxy. I do this in Python, using these settings:

proxy = Client("localhost:30050", params={"port": 30052, "trustAllServers": True})

chrome_options = Options()
chrome_options.binary_location = "/opt/google/chrome/chrome"
chrome_options.add_argument("disable-3d-apis")
chrome_options.add_argument("disable-accelerated-video")
chrome_options.add_argument("disable-background-mode")
chrome_options.add_argument("disable-dev-shm-usage")
chrome_options.add_argument("disable-extensions")
chrome_options.add_argument("disable-gpu")
chrome_options.add_argument("disable-notifications")
chrome_options.add_argument("disable-plugins")
chrome_options.add_argument("disable-preconnect")
chrome_options.add_argument("disable-translate")
chrome_options.add_argument("disable-preconnect")
chrome_options.add_argument("disable-session-crashed-bubble")
chrome_options.add_argument("ignore-certificate-errors")
chrome_options.add_argument("no-experiments")
chrome_options.add_argument("no-pings")
chrome_options.add_argument("no-sandbox")
chrome_options.add_argument("proxy-server=http://localhost:30052")
chrome_options.add_argument("start-maximized")
chrome_options.add_argument("headless")

driver = webdriver.Chrome("/opt/google/chromedriver", options=chrome_options)

3. Load a webpage: driver.get("https://www.google.com/")
4. Wait for proxy traffic to stop: curl -X PUT http://localhost:30050/proxy/30052/wait?quietPeriodInMs=1&timeoutInMs=120000
5. /wait will timeout.

Expected behavior
Calling PUT /wait with quietPeriodInMs=1 and timeoutInMs=120000 should return fairly immediately once a page finishes loading, since there should definitely be a quiet period of 1 millisecond in a 2 minute window.

Please complete the following information:

• OS: Ubuntu 20.04
• Browser: chromedriver 88.0.4324.96
• Version: 2.1.2