Python Requests hanging/freezing

Patching the documented "send" function will fix this for all requests - even in many dependent libraries and sdk's. When patching libs, be sure to patch supported/documented functions, otherwise you may wind up silently losing the effect of your patch.

import requests

DEFAULT_TIMEOUT = 180

old_send = requests.Session.send

def new_send(*args, **kwargs):
     if kwargs.get("timeout", None) is None:
         kwargs["timeout"] = DEFAULT_TIMEOUT
     return old_send(*args, **kwargs)

requests.Session.send = new_send

The effects of not having any timeout are quite severe, and the use of a default timeout can almost never break anything - because TCP itself has timeouts as well.

On Windows the default TCP timeout is 240 seconds, TCP RFC recommend a minimum of 100 seconds for RTO*retry. Somewhere in that range is a safe default.

Seems like setting a (read) timeout might help you.

Something along the lines of:

response = response.get(url, timeout=5)

(This will set both connect and read timeout to 5 seconds.)

In requests, unfortunately, neither connect nor read timeouts are set by default, even though the docs say it's good to set it:

Most requests to external servers should have a timeout attached, in case the server is not responding in a timely manner. By default, requests do not time out unless a timeout value is set explicitly. Without a timeout, your code may hang for minutes or more.

Just for completeness, the connect timeout is the number of seconds requests will wait for your client to establish a connection to a remote machine, and the read timeout is the number of seconds the client will wait between bytes sent from the server.

To set timeout globally instead of specifying in every request:

from requests.adapters import TimeoutSauce

REQUESTS_TIMEOUT_SECONDS = float(os.getenv("REQUESTS_TIMEOUT_SECONDS", 5))

class CustomTimeout(TimeoutSauce):
    def __init__(self, *args, **kwargs):
        if kwargs["connect"] is None:
            kwargs["connect"] = REQUESTS_TIMEOUT_SECONDS
        if kwargs["read"] is None:
            kwargs["read"] = REQUESTS_TIMEOUT_SECONDS
        super().__init__(*args, **kwargs)


# Set it globally, instead of specifying ``timeout=..`` kwarg on each call.
requests.adapters.TimeoutSauce = CustomTimeout


sess = requests.Session()
sess.get(...)
sess.post(...)