Files

412 lines
14 KiB
Python

#!/usr/bin/env python3
"""Pick a PIA region/server and write a WireGuard config for Gluetun."""
from __future__ import annotations
import argparse
import json
import os
import random
import re
import socket
import subprocess
import sys
import time
from concurrent.futures import ThreadPoolExecutor, as_completed
from datetime import datetime
from pathlib import Path
from typing import Any
import pia
def log(msg: str) -> None:
print(f"[{datetime.now().astimezone().isoformat(timespec='seconds')}] {msg}", file=sys.stderr)
def require_env(name: str) -> str:
value = os.environ.get(name, "")
if not value:
raise SystemExit(f"Missing required env var: {name}")
return value
def parse_list(raw: str) -> list[str]:
raw = raw.strip()
if not raw:
return []
if raw.startswith("["):
data = json.loads(raw)
if not isinstance(data, list):
raise SystemExit("Expected a JSON array")
return [str(item).strip() for item in data if str(item).strip()]
return [part.strip() for part in raw.split(",") if part.strip()]
def parse_regions() -> list[str]:
regions = parse_list(require_env("PIA_REGIONS"))
if not regions:
raise SystemExit("PIA_REGIONS is empty after parsing")
return regions
def read_state(state_path: Path) -> dict[str, Any]:
if not state_path.is_file():
return {}
try:
data = json.loads(state_path.read_text(encoding="utf-8"))
except (OSError, json.JSONDecodeError):
return {}
return data if isinstance(data, dict) else {}
def tcp_latency_ms(ip: str, port: int, timeout: float) -> float | None:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.settimeout(timeout)
started = time.perf_counter()
try:
sock.connect((ip, port))
return (time.perf_counter() - started) * 1000.0
except OSError:
return None
finally:
sock.close()
def average_tcp_latency_ms(ip: str, port: int, timeout: float, samples: int) -> float | None:
readings: list[float] = []
for _ in range(samples):
value = tcp_latency_ms(ip, port, timeout)
if value is None:
return None
readings.append(value)
return sum(readings) / len(readings)
def probe_servers(servers: list[pia.WgServer]) -> list[dict[str, Any]]:
"""Probe all servers and return per-IP results sorted by latency."""
port = int(os.environ.get("LATENCY_PORT", "1337"))
timeout = float(os.environ.get("LATENCY_TIMEOUT_SECONDS", "2"))
samples = max(1, int(os.environ.get("LATENCY_SAMPLES", "2")))
results: list[dict[str, Any]] = []
with ThreadPoolExecutor(max_workers=min(32, max(1, len(servers)))) as pool:
futures = {
pool.submit(average_tcp_latency_ms, server.ip, port, timeout, samples): server
for server in servers
}
for future in as_completed(futures):
server = futures[future]
value = future.result()
results.append(
{
"region": server.region,
"server_ip": server.ip,
"server_cn": server.cn,
"latency_ms": None if value is None else round(value, 2),
}
)
results.sort(
key=lambda item: (
item["latency_ms"] is None,
item["latency_ms"] if item["latency_ms"] is not None else float("inf"),
item["region"],
item["server_ip"],
)
)
for item in results:
latency = "timeout" if item["latency_ms"] is None else f"{item['latency_ms']:.2f}ms"
log(f"Latency {item['region']}: {latency} ({item['server_cn']}/{item['server_ip']})")
return results
def pick_fastest(
candidates: list[str],
previous_region: str | None,
previous_server_ip: str | None,
*,
exclude_ips: set[str] | None = None,
apply_margin: bool = True,
) -> tuple[pia.WgServer, list[dict[str, Any]]]:
exclude_ips = exclude_ips or set()
margin = float(os.environ.get("LATENCY_SWITCH_MARGIN_MS", "15"))
serverlist = pia.fetch_serverlist()
servers: list[pia.WgServer] = []
for region_id in candidates:
for server in pia.region_wg_servers(serverlist, region_id):
if server.ip in exclude_ips:
continue
servers.append(server)
if not servers:
raise SystemExit("No reachable WireGuard servers left after excludes")
results = probe_servers(servers)
reachable = [item for item in results if item["latency_ms"] is not None]
if not reachable:
raise SystemExit("All latency probes failed; cannot select fastest server")
winner = reachable[0]
if apply_margin and previous_server_ip and previous_server_ip not in exclude_ips:
previous_result = next(
(item for item in reachable if item["server_ip"] == previous_server_ip),
None,
)
if previous_result is not None:
improvement = previous_result["latency_ms"] - winner["latency_ms"]
if winner["server_ip"] != previous_server_ip and improvement < margin:
log(
f"Keeping current server {previous_server_ip} "
f"({previous_result['latency_ms']:.2f}ms); "
f"best {winner['server_ip']} only {improvement:.2f}ms faster "
f"(margin {margin:g}ms)"
)
winner = previous_result
elif winner["server_ip"] == previous_server_ip:
log(f"Current endpoint {previous_server_ip} is still fastest")
server = pia.WgServer(
region=winner["region"],
ip=winner["server_ip"],
cn=winner["server_cn"],
)
log(f"Selected {server.region} via {server.cn} ({server.ip}) at {winner['latency_ms']:.2f}ms")
return server, results
def pick_random(
candidates: list[str],
previous_region: str | None,
*,
exclude_ips: set[str] | None = None,
) -> pia.WgServer:
exclude_ips = exclude_ips or set()
serverlist = pia.fetch_serverlist()
pool = [region for region in candidates if region != previous_region] or list(candidates)
if previous_region and previous_region not in pool and len(candidates) == 1:
log(f"Only one region configured; reusing previous: {previous_region}")
elif previous_region and previous_region not in pool:
log(f"Excluding previous region: {previous_region}")
random.shuffle(pool)
for region_id in pool:
servers = [
server
for server in pia.region_wg_servers(serverlist, region_id)
if server.ip not in exclude_ips
]
if servers:
server = random.choice(servers)
log(f"Randomly selected {server.region} via {server.cn} ({server.ip})")
return server
raise SystemExit("No WireGuard servers left after excludes")
def pick_server(
state_path: Path,
*,
exclude_ips: set[str] | None = None,
apply_margin: bool = True,
) -> tuple[pia.WgServer, str, list[dict[str, Any]]]:
regions = parse_regions()
state = read_state(state_path)
previous_region = state.get("region") if isinstance(state.get("region"), str) else None
previous_server_ip = state.get("server_ip") if isinstance(state.get("server_ip"), str) else None
mode = os.environ.get("REGION_SELECT", "fastest").strip().lower() or "fastest"
if mode == "random":
return pick_random(regions, previous_region, exclude_ips=exclude_ips), mode, []
if mode != "fastest":
raise SystemExit(f"Invalid REGION_SELECT '{mode}' (expected fastest|random)")
server, results = pick_fastest(
regions,
previous_region,
previous_server_ip,
exclude_ips=exclude_ips,
apply_margin=apply_margin,
)
return server, mode, results
def parse_restart_containers() -> list[str]:
gluetun = os.environ.get("GLUETUN_CONTAINER", "m3u-filter-vpn").strip() or "m3u-filter-vpn"
ordered = [gluetun]
seen = {gluetun}
for container in parse_list(os.environ.get("RESTART_CONTAINERS", "")):
if container in seen:
continue
ordered.append(container)
seen.add(container)
return ordered
def restart_containers(containers: list[str]) -> None:
if not containers:
raise SystemExit("No containers configured to restart")
for container in containers:
log(f"Restarting container: {container}")
result = subprocess.run(["docker", "restart", container], check=False)
if result.returncode != 0:
raise SystemExit(f"docker restart failed for container={container}")
def write_state(
state_path: Path,
server: pia.WgServer,
mode: str,
restarted: list[str],
latency_results: list[dict[str, Any]],
*,
skipped: bool = False,
) -> None:
previous = read_state(state_path)
winner = next(
(
item
for item in latency_results
if item.get("region") == server.region and item.get("server_ip") == server.ip
),
next((item for item in latency_results if item.get("server_ip") == server.ip), None),
)
now = datetime.now().astimezone().isoformat(timespec="seconds")
payload: dict[str, Any] = {
"region": server.region,
"server_ip": server.ip,
"server_cn": server.cn,
"selection": mode,
"wg_config": os.environ.get("WG_CONFIG_PATH", "/config/wireguard/wg0.conf"),
"restarted_containers": restarted,
"last_checked_at": now,
"skipped_regeneration": skipped,
}
if skipped and isinstance(previous.get("rotated_at"), str):
payload["rotated_at"] = previous["rotated_at"]
else:
payload["rotated_at"] = now
if winner and winner.get("latency_ms") is not None:
payload["latency_ms"] = winner["latency_ms"]
elif skipped and previous.get("latency_ms") is not None:
payload["latency_ms"] = previous["latency_ms"]
if latency_results:
payload["latency_results"] = latency_results
state_path.parent.mkdir(parents=True, exist_ok=True)
state_path.write_text(json.dumps(payload, indent=2) + "\n", encoding="utf-8")
state_path.chmod(0o644)
def config_looks_valid(wg_path: Path) -> bool:
if not wg_path.is_file():
return False
text = wg_path.read_text(encoding="utf-8", errors="replace")
return bool(re.search(r"^\[Interface\]", text, flags=re.MULTILINE))
def parse_args(argv: list[str]) -> argparse.Namespace:
parser = argparse.ArgumentParser(description="Rotate PIA WireGuard config for Gluetun")
parser.add_argument("--list-regions", action="store_true")
parser.add_argument(
"--skip-same-server",
action="store_true",
help="Skip token/addKey/restarts when the selected server is unchanged",
)
parser.add_argument(
"--force",
action="store_true",
help="Always generate a new keypair and restart containers",
)
parser.add_argument(
"--exclude-server",
action="append",
default=[],
help="Exclude this server IP from selection (repeatable)",
)
return parser.parse_args(argv)
def rotate_once(args: argparse.Namespace) -> None:
require_env("PIA_USER")
require_env("PIA_PASS")
require_env("PIA_REGIONS")
state_path = Path(os.environ.get("ROTATOR_STATE_PATH", "/config/rotator-state.json"))
wg_path = Path(os.environ.get("WG_CONFIG_PATH", "/config/wireguard/wg0.conf"))
state = read_state(state_path)
exclude_ips = {ip for ip in args.exclude_server if ip}
# Unhealthy/force path wants true #1/#2 ranking without stickiness margin.
apply_margin = not args.force and not exclude_ips
server, mode, latency_results = pick_server(
state_path,
exclude_ips=exclude_ips,
apply_margin=apply_margin,
)
log(f"Selected endpoint: {server.region} / {server.cn} / {server.ip} (mode={mode})")
previous_ip = state.get("server_ip") if isinstance(state.get("server_ip"), str) else None
if args.skip_same_server and not args.force and previous_ip == server.ip and config_looks_valid(wg_path):
log(
f"Skipping PIA token/addKey; endpoint unchanged ({server.region}/{server.ip})"
)
write_state(
state_path,
server,
mode,
[],
latency_results,
skipped=True,
)
log(f"Rotation skipped for {server.region}/{server.ip}")
return
# Write temp file on the same filesystem as the destination so os.replace works
# across Docker bind mounts (/tmp is often a different device than /config).
wg_path.parent.mkdir(parents=True, exist_ok=True)
tmp_conf = wg_path.with_name(wg_path.name + ".tmp")
try:
log("Generating WireGuard config via native PIA client")
pia.generate_wg_config(
require_env("PIA_USER"),
require_env("PIA_PASS"),
server,
tmp_conf,
)
text = tmp_conf.read_text(encoding="utf-8", errors="replace")
if not re.search(r"^\[Interface\]", text, flags=re.MULTILINE):
raise SystemExit("Generated config missing [Interface] section")
os.replace(tmp_conf, wg_path)
wg_path.chmod(0o600)
log(f"Wrote {wg_path}")
finally:
tmp_conf.unlink(missing_ok=True)
restarted = parse_restart_containers()
restart_containers(restarted)
write_state(state_path, server, mode, restarted, latency_results, skipped=False)
log(f"Rotation complete for {server.region}/{server.ip}")
def list_regions_main() -> None:
for region in pia.list_regions():
print(
f"{region['id']:<35} {region['name']:<35} "
f"country={region['country']:<4} port-forward={region['port_forward']!s:<5} "
f"offline={region['offline']} wg={region['wg_servers']}"
)
if __name__ == "__main__":
# Compat: `rotate.py list-regions`
argv = sys.argv[1:]
if argv and argv[0] == "list-regions":
argv = ["--list-regions", *argv[1:]]
args = parse_args(argv)
if args.list_regions:
list_regions_main()
else:
rotate_once(args)