sockfilter

Block socket creation based on hostname/port to suppress unwanted network activity.

Usage

The intended use is for making sure your unit tests don't make network connections. Activate sockfilter with a predicate like:

# only allow http connections to localhost
def socket_address_allowed(address):
    return (address.host in ['localhost', '127.0.0.1'] and
            address.port == 80)

sockfilter.enable(socket_address_allowed)

Any subsequent attempts to open a connection at an address not satisfying the predicate will raise sockfilter.SockFilterError.

with_sockfiltering decorator

from sockfilter import with_sockfiltering

@with_sockfiltering(socket_address_allowed)
def test_foo():
    foo()

sockfiltering context manager

from sockfilter import sockfiltering

def test_foo():
    with sockfiltering(socket_address_allowed):
        foo()

enable and disable

import sockfilter
from unittest import TestCase

class FooTest(TestCase):

    def setUp(self):
        sockfilter.enable(socket_address_allowed)

    def tearDown(self):
        sockfilter.disable()

    def test_foo(self):
        foo()

Under the hood

Sockfilter works by monkey-patching Python's socket library, inspired by HTTPretty.