HTTP_PROXY / HTTPS_PROXY in Python: trust_env, NO_PROXY and the pitfalls nobody documents — https://quantumproxies.io/rotating-proxies

python-proxy-env-vars.py

# HTTP_PROXY / HTTPS_PROXY in Python: the pitfalls nobody documents.
#
# 1) requests reads env vars ONLY if trust_env is True (default) — and
#    HTTPS_PROXY must still be an http:// URL (it's the scheme of the
#    *target*, not of the proxy).
# 2) NO_PROXY beats both — a stray NO_PROXY=* silently disables everything.
# 3) urllib/requests lowercase vs uppercase: both are read, lowercase wins.
#
# Proxy used in the example: QuantumProxies rotating residential
# https://quantumproxies.io/rotating-proxies (creds: app.quantumproxies.io/register)

import os
import requests

os.environ["HTTP_PROXY"] = "http://USER-country-us:PASS@residentialboson.quantumproxies.io:9000"
os.environ["HTTPS_PROXY"] = os.environ["HTTP_PROXY"]   # yes, http:// for both
os.environ.pop("NO_PROXY", None)                       # pitfall #2

print(requests.get("https://ipinfo.io/json", timeout=30).json())

# Opting OUT for one call while env vars are set:
s = requests.Session()
s.trust_env = False                # ignore proxy env entirely
print(s.get("https://ipinfo.io/json", timeout=30).json())

# Opting IN explicitly (wins over env, survives trust_env=False):
proxies = {"http": os.environ["HTTP_PROXY"], "https": os.environ["HTTP_PROXY"]}
print(requests.get("https://ipinfo.io/json", proxies=proxies, timeout=30).json())