diff options
Diffstat (limited to '.venv/lib/python3.12/site-packages/aiohttp/resolver.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/aiohttp/resolver.py | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/aiohttp/resolver.py b/.venv/lib/python3.12/site-packages/aiohttp/resolver.py new file mode 100644 index 00000000..e14179cc --- /dev/null +++ b/.venv/lib/python3.12/site-packages/aiohttp/resolver.py @@ -0,0 +1,190 @@ +import asyncio +import socket +from typing import Any, Dict, List, Optional, Tuple, Type, Union + +from .abc import AbstractResolver, ResolveResult + +__all__ = ("ThreadedResolver", "AsyncResolver", "DefaultResolver") + + +try: + import aiodns + + aiodns_default = hasattr(aiodns.DNSResolver, "getaddrinfo") +except ImportError: # pragma: no cover + aiodns = None # type: ignore[assignment] + aiodns_default = False + + +_NUMERIC_SOCKET_FLAGS = socket.AI_NUMERICHOST | socket.AI_NUMERICSERV +_NAME_SOCKET_FLAGS = socket.NI_NUMERICHOST | socket.NI_NUMERICSERV +_AI_ADDRCONFIG = socket.AI_ADDRCONFIG +if hasattr(socket, "AI_MASK"): + _AI_ADDRCONFIG &= socket.AI_MASK + + +class ThreadedResolver(AbstractResolver): + """Threaded resolver. + + Uses an Executor for synchronous getaddrinfo() calls. + concurrent.futures.ThreadPoolExecutor is used by default. + """ + + def __init__(self, loop: Optional[asyncio.AbstractEventLoop] = None) -> None: + self._loop = loop or asyncio.get_running_loop() + + async def resolve( + self, host: str, port: int = 0, family: socket.AddressFamily = socket.AF_INET + ) -> List[ResolveResult]: + infos = await self._loop.getaddrinfo( + host, + port, + type=socket.SOCK_STREAM, + family=family, + flags=_AI_ADDRCONFIG, + ) + + hosts: List[ResolveResult] = [] + for family, _, proto, _, address in infos: + if family == socket.AF_INET6: + if len(address) < 3: + # IPv6 is not supported by Python build, + # or IPv6 is not enabled in the host + continue + if address[3]: + # This is essential for link-local IPv6 addresses. + # LL IPv6 is a VERY rare case. Strictly speaking, we should use + # getnameinfo() unconditionally, but performance makes sense. + resolved_host, _port = await self._loop.getnameinfo( + address, _NAME_SOCKET_FLAGS + ) + port = int(_port) + else: + resolved_host, port = address[:2] + else: # IPv4 + assert family == socket.AF_INET + resolved_host, port = address # type: ignore[misc] + hosts.append( + ResolveResult( + hostname=host, + host=resolved_host, + port=port, + family=family, + proto=proto, + flags=_NUMERIC_SOCKET_FLAGS, + ) + ) + + return hosts + + async def close(self) -> None: + pass + + +class AsyncResolver(AbstractResolver): + """Use the `aiodns` package to make asynchronous DNS lookups""" + + def __init__( + self, + loop: Optional[asyncio.AbstractEventLoop] = None, + *args: Any, + **kwargs: Any, + ) -> None: + if aiodns is None: + raise RuntimeError("Resolver requires aiodns library") + + self._resolver = aiodns.DNSResolver(*args, **kwargs) + + if not hasattr(self._resolver, "gethostbyname"): + # aiodns 1.1 is not available, fallback to DNSResolver.query + self.resolve = self._resolve_with_query # type: ignore + + async def resolve( + self, host: str, port: int = 0, family: socket.AddressFamily = socket.AF_INET + ) -> List[ResolveResult]: + try: + resp = await self._resolver.getaddrinfo( + host, + port=port, + type=socket.SOCK_STREAM, + family=family, + flags=_AI_ADDRCONFIG, + ) + except aiodns.error.DNSError as exc: + msg = exc.args[1] if len(exc.args) >= 1 else "DNS lookup failed" + raise OSError(None, msg) from exc + hosts: List[ResolveResult] = [] + for node in resp.nodes: + address: Union[Tuple[bytes, int], Tuple[bytes, int, int, int]] = node.addr + family = node.family + if family == socket.AF_INET6: + if len(address) > 3 and address[3]: + # This is essential for link-local IPv6 addresses. + # LL IPv6 is a VERY rare case. Strictly speaking, we should use + # getnameinfo() unconditionally, but performance makes sense. + result = await self._resolver.getnameinfo( + (address[0].decode("ascii"), *address[1:]), + _NAME_SOCKET_FLAGS, + ) + resolved_host = result.node + else: + resolved_host = address[0].decode("ascii") + port = address[1] + else: # IPv4 + assert family == socket.AF_INET + resolved_host = address[0].decode("ascii") + port = address[1] + hosts.append( + ResolveResult( + hostname=host, + host=resolved_host, + port=port, + family=family, + proto=0, + flags=_NUMERIC_SOCKET_FLAGS, + ) + ) + + if not hosts: + raise OSError(None, "DNS lookup failed") + + return hosts + + async def _resolve_with_query( + self, host: str, port: int = 0, family: int = socket.AF_INET + ) -> List[Dict[str, Any]]: + if family == socket.AF_INET6: + qtype = "AAAA" + else: + qtype = "A" + + try: + resp = await self._resolver.query(host, qtype) + except aiodns.error.DNSError as exc: + msg = exc.args[1] if len(exc.args) >= 1 else "DNS lookup failed" + raise OSError(None, msg) from exc + + hosts = [] + for rr in resp: + hosts.append( + { + "hostname": host, + "host": rr.host, + "port": port, + "family": family, + "proto": 0, + "flags": socket.AI_NUMERICHOST, + } + ) + + if not hosts: + raise OSError(None, "DNS lookup failed") + + return hosts + + async def close(self) -> None: + self._resolver.cancel() + + +_DefaultType = Type[Union[AsyncResolver, ThreadedResolver]] +DefaultResolver: _DefaultType = AsyncResolver if aiodns_default else ThreadedResolver |