Using arbitrary local IPv6 address with AnyIP

[stefanodvx]

Hi! I was wondering how to port this HTTPAdapter from requests to an AsyncHTTPTransport of httpx.

from requests.adapters import HTTPAdapter
from urllib3 import poolmanager
import socket
import ipaddress
import random
import requests


IP_FREEBIND = 15

class SubrollAdapter(HTTPAdapter):
    def __init__(self, *args, source_address: str, **kwargs):
        self.source_address = (source_address, 0)
        super(SubrollAdapter, self).__init__(*args, **kwargs)

    def init_poolmanager(self, connections, maxsize, **kwargs):
        socket_options = [(socket.SOL_IP, IP_FREEBIND, 1)]

        self.poolmanager = poolmanager.PoolManager(
            num_pools=connections,
            maxsize=maxsize,
            source_address=self.source_address,
            socket_options=socket_options,
            **kwargs
        )

    def proxy_manager_for(self, *args, **kwargs):
        kwargs["source_address"] = self.source_address
        return super(SubrollAdapter, self).proxy_manager_for(*args, **kwargs)

This is used to assign an arbitrary IPv6 as a "proxy" for requests, using Linux AnyIP feature. Thank you so much :)