SSL certificate expiry watch in Python
Minimal script that checks an SSL certificate and alerts 14 days before expiry.
Recipe
python
import ssl, socket, datetime
def days_left(host: str, port: int = 443) -> int:
ctx = ssl.create_default_context()
with socket.create_connection((host, port), timeout=10) as sock:
with ctx.wrap_socket(sock, server_hostname=host) as ss:
not_after = ss.getpeercert()["notAfter"]
exp = datetime.datetime.strptime(not_after, "%b %d %H:%M:%S %Y %Z")
return (exp - datetime.datetime.utcnow()).days
if days_left("example.com") < 14:
raise SystemExit("SSL expiring soon")Same thing in Enterno.io
Enterno SSL check + monitor: automatic email + Telegram at T-14 and T-3 days before expiry, full chain validation (intermediate, OCSP, cipher).
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