如何检测python请求中的断开连接保持活动连接？

Question

I am using python-requests to connect to a live feed. After I connect, I use iter_lines to go over the data as it arrives. I am trying to detect a disconnect when it happens, currently without success.

The way I detect disconnects currently, is by waiting a maximum of 30 seconds for a new line to arrive, and if it doesn't, I restart the connection. The problem is that I miss the data that arrives within these 30 seconds.

As a test, I tried turning off my wifi in the middle and seeing if anything (like Response.status_code) changes, but it does not.

Example code:

r = requests.get(url, stream=True)

while True:
     time.sleep(1)
     print(r.status_code)

I expected the print to show 200 when connected and SOME_SORT_OF_ERROR when I turn the wifi off, but I keep on seeing 200.

Does anyone know of a way to detect the disconnect?

Answer 1

As the python requests doc says, the keep alive is 100% automatic in a session. You should read the lines this way:

r = requests.get(url, stream=True)

for line in r.iter_lines():
    if line:
        print json.loads(line)

You can read more about it here