utils/crdt-sync/tool/_oauth_callback.py
Krzysztof kuhy Rudnicki 6154dc09bf Pin pre-commit's ruff to 0.16.7 and satisfy the CPY001 it brings
The three Python packages pinned ruff twice at different versions:
requirements.txt at 0.16.7, .pre-commit-config.yaml at v0.15.2. Only the
older one ever ran, so `select = ["ALL"]` was enforced two minor versions
behind. Measured before aligning: v0.15.2 reports 0 findings, every 0.16.x
reports CPY001 on each file -- 70 crdt-sync, 23 freedays, 71 gatelock, and
no other rule.

Resolved by adding the notice rather than ignoring the rule, so the gate
keeps its teeth.

Two gatelock modules sat at exactly the 250-line cap, so a one-line header
tipped them to 251. Both are split along a real seam rather than shaved:

  _widget_fills.py    colour arithmetic over LockConfig, no tkinter import
  _surfaces_focus.py  selects among existing surfaces, never mutates them

The focus split keeps _surfaces.py's documented containment (it stays the
only module that creates, moves or destroys windows), and the static guard
in test_recovery_invariants.py globs _surfaces*.py, so the new sibling is
covered with no list to extend. widgets.py re-exports the fills helpers,
which keeps gatelock.widgets the single public surface its tests import.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019kMvSMtsVMB3d2uoZ56pbp
2026-09-12 18:11:24 +02:00

107 lines
3.9 KiB
Python

# Copyright (c) 2026 Krzysztof Rudnicki
"""The one-shot local HTTP server that catches Google's OAuth redirect.
Split from :mod:`google_id_token`, which keeps the token exchange. Google
redirects the browser back to ``http://localhost:<port>`` with the code in the
query string, so something has to be listening on a free port for exactly one
request and then stop.
"""
from __future__ import annotations
import http.server
import logging
import socket
import threading
import time
from typing import ClassVar
import urllib.parse
_logger = logging.getLogger(__name__)
_CONSENT_TIMEOUT_SECONDS = 300
class _CallbackHandler(http.server.BaseHTTPRequestHandler):
"""Captures the ``code`` (or ``error``) Google redirects back with."""
# Set by the server owner before serving. Class attributes because
# BaseHTTPRequestHandler is instantiated per request by the server, so
# there is no instance to hand them to.
expected_state: ClassVar[str] = ""
result: ClassVar[dict[str, str]] = {}
def do_GET(self) -> None:
"""Record the query parameters and show a closable page.
Requests that carry neither a ``code`` nor an ``error`` are answered
but *not* recorded: browsers fetch ``/favicon.ico`` against the
redirect origin, and letting that count as the callback ends the flow
before Google ever redirects, which surfaces as a consent timeout.
"""
query = urllib.parse.urlparse(self.path).query
params = {k: v[0] for k, v in urllib.parse.parse_qs(query).items()}
if "code" not in params and "error" not in params:
self.send_response(204)
self.send_header("Content-Length", "0")
self.end_headers()
return
type(self).result = params
ok = "code" in params and params.get("state") == self.expected_state
body = (
b"<html><body><h2>Done - you can close this tab.</h2></body></html>"
if ok
else b"<html><body><h2>Authorization failed.</h2></body></html>"
)
self.send_response(200 if ok else 400)
self.send_header("Content-Type", "text/html; charset=utf-8")
self.send_header("Content-Length", str(len(body)))
self.end_headers()
self.wfile.write(body)
def log_message(self, *args: object) -> None:
"""Silence the default stderr request logging."""
def _free_port() -> int:
with socket.socket() as sock:
sock.bind(("127.0.0.1", 0))
return int(sock.getsockname()[1])
def _start_callback_server(
port: int,
state: str,
) -> tuple[http.server.HTTPServer, threading.Thread]:
"""Listen on ``port`` until the OAuth callback arrives.
Serves in a loop rather than handling exactly one request: the first
request to reach this port is often a favicon fetch or a speculative
preconnect, and retiring the server on it leaves nothing listening when
Google finally redirects -- which surfaces as a consent timeout.
Args:
port: The loopback port to bind.
state: The value the callback must echo back.
Returns:
The server and the thread serving it, so the caller can join and close.
"""
_CallbackHandler.expected_state = state
_CallbackHandler.result = {}
server = http.server.HTTPServer(("127.0.0.1", port), _CallbackHandler)
# Bounded so handle_request() returns periodically instead of blocking
# forever; without it the loop could not notice the deadline and the
# daemon thread would sit on the socket after the caller gave up.
server.timeout = 1.0
deadline = time.monotonic() + _CONSENT_TIMEOUT_SECONDS
def _serve_until_callback() -> None:
while not _CallbackHandler.result and time.monotonic() < deadline:
server.handle_request()
thread = threading.Thread(target=_serve_until_callback, daemon=True)
thread.start()
return server, thread