Files
openstack-api-simulator/app/contracts/importer.py
T
inecs 6033967e6a Initial commit: stateful OpenStack API laboratory simulator.
Ship Keystone auth, multi-service handlers (Yoga→Dalmatian), Compose/Helm
packaging, API contract packs, and pytest/Pulumi coverage labs.
2026-07-18 04:26:48 +03:00

111 lines
4.4 KiB
Python

"""Network-constrained remote contract retrieval."""
from __future__ import annotations
import asyncio
import ipaddress
import socket
from collections.abc import Awaitable, Callable
from dataclasses import dataclass
from urllib.parse import urljoin, urlsplit
import httpx
from app.contracts.source import SourceError
Resolver = Callable[[str], Awaitable[tuple[str, ...]]]
async def resolve_host(host: str) -> tuple[str, ...]:
loop = asyncio.get_running_loop()
results = await loop.getaddrinfo(host, 443, type=socket.SOCK_STREAM)
return tuple(sorted({str(result[4][0]) for result in results}))
def validate_remote_url(url: str, allowed_hosts: frozenset[str]) -> str:
parsed = urlsplit(url)
if parsed.scheme != "https":
raise SourceError("remote imports require HTTPS")
if parsed.username or parsed.password or parsed.port not in (None, 443):
raise SourceError("remote URL contains forbidden authority components")
host = (parsed.hostname or "").rstrip(".").lower()
if host not in allowed_hosts:
raise SourceError("remote host is not in the official-domain allowlist")
if parsed.fragment:
raise SourceError("remote URL fragments are not allowed")
return host
# Fake-IP pools used by local proxies (Clash, Surge, etc.) still route to public hosts.
_FAKE_IP_NETWORK = ipaddress.ip_network("198.18.0.0/15")
def _is_allowed_resolved_address(address: ipaddress.IPv4Address | ipaddress.IPv6Address) -> bool:
if address.is_global:
return True
mapped = address.ipv4_mapped if isinstance(address, ipaddress.IPv6Address) else None
if mapped is not None and mapped in _FAKE_IP_NETWORK:
return True
if isinstance(address, ipaddress.IPv4Address) and address in _FAKE_IP_NETWORK:
return True
return False
def validate_public_addresses(addresses: tuple[str, ...]) -> None:
if not addresses:
raise SourceError("remote host did not resolve")
for value in addresses:
address = ipaddress.ip_address(value)
if not _is_allowed_resolved_address(address):
raise SourceError(f"remote host resolved to a non-public address: {value}")
@dataclass(frozen=True, slots=True)
class RemoteSourceImporter:
url: str
allowed_hosts: frozenset[str] = frozenset({"pve.proxmox.com"})
max_bytes: int = 16 * 1024 * 1024
max_redirects: int = 3
retries: int = 2
timeout_seconds: float = 20.0
resolver: Resolver = resolve_host
transport: httpx.AsyncBaseTransport | None = None
async def load(self) -> bytes:
current = self.url
timeout = httpx.Timeout(self.timeout_seconds)
async with httpx.AsyncClient(
follow_redirects=False, timeout=timeout, transport=self.transport
) as client:
for redirect_count in range(self.max_redirects + 1):
host = validate_remote_url(current, self.allowed_hosts)
validate_public_addresses(await self.resolver(host))
response = await self._request(client, current)
if response.is_redirect:
if redirect_count == self.max_redirects:
raise SourceError("remote import exceeded redirect limit")
location = response.headers.get("location")
if not location:
raise SourceError("remote redirect has no location")
current = urljoin(current, location)
continue
response.raise_for_status()
content_length = response.headers.get("content-length")
if content_length and int(content_length) > self.max_bytes:
raise SourceError("remote artifact exceeds size limit")
content = response.content
if len(content) > self.max_bytes:
raise SourceError("remote artifact exceeds size limit")
return content
raise SourceError("remote import failed")
async def _request(self, client: httpx.AsyncClient, url: str) -> httpx.Response:
for attempt in range(self.retries + 1):
try:
return await client.get(url)
except (httpx.TimeoutException, httpx.NetworkError):
if attempt == self.retries:
raise
await asyncio.sleep(0.1 * (2**attempt))
raise SourceError("remote import retry loop exhausted")