mirror of https://github.com/sgoudham/Enso-Bot.git
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
113 lines
3.5 KiB
Python
113 lines
3.5 KiB
Python
5 years ago
|
import asyncio
|
||
|
import socket
|
||
|
from typing import Any, Dict, List, Optional
|
||
|
|
||
|
from .abc import AbstractResolver
|
||
|
from .helpers import get_running_loop
|
||
|
|
||
|
__all__ = ('ThreadedResolver', 'AsyncResolver', 'DefaultResolver')
|
||
|
|
||
|
try:
|
||
|
import aiodns
|
||
|
# aiodns_default = hasattr(aiodns.DNSResolver, 'gethostbyname')
|
||
|
except ImportError: # pragma: no cover
|
||
|
aiodns = None
|
||
|
|
||
|
aiodns_default = False
|
||
|
|
||
|
|
||
|
class ThreadedResolver(AbstractResolver):
|
||
|
"""Use Executor for synchronous getaddrinfo() calls, which defaults to
|
||
|
concurrent.futures.ThreadPoolExecutor.
|
||
|
"""
|
||
|
|
||
|
def __init__(self, loop: Optional[asyncio.AbstractEventLoop]=None) -> None:
|
||
|
self._loop = get_running_loop(loop)
|
||
|
|
||
|
async def resolve(self, host: str, port: int=0,
|
||
|
family: int=socket.AF_INET) -> List[Dict[str, Any]]:
|
||
|
infos = await self._loop.getaddrinfo(
|
||
|
host, port, type=socket.SOCK_STREAM, family=family)
|
||
|
|
||
|
hosts = []
|
||
|
for family, _, proto, _, address in infos:
|
||
|
hosts.append(
|
||
|
{'hostname': host,
|
||
|
'host': address[0], 'port': address[1],
|
||
|
'family': family, 'proto': proto,
|
||
|
'flags': socket.AI_NUMERICHOST})
|
||
|
|
||
|
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._loop = get_running_loop(loop)
|
||
|
self._resolver = aiodns.DNSResolver(*args, loop=loop, **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: int=socket.AF_INET) -> List[Dict[str, Any]]:
|
||
|
try:
|
||
|
resp = await self._resolver.gethostbyname(host, family)
|
||
|
except aiodns.error.DNSError as exc:
|
||
|
msg = exc.args[1] if len(exc.args) >= 1 else "DNS lookup failed"
|
||
|
raise OSError(msg) from exc
|
||
|
hosts = []
|
||
|
for address in resp.addresses:
|
||
|
hosts.append(
|
||
|
{'hostname': host,
|
||
|
'host': address, 'port': port,
|
||
|
'family': family, 'proto': 0,
|
||
|
'flags': socket.AI_NUMERICHOST})
|
||
|
|
||
|
if not hosts:
|
||
|
raise OSError("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(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("DNS lookup failed")
|
||
|
|
||
|
return hosts
|
||
|
|
||
|
async def close(self) -> None:
|
||
|
return self._resolver.cancel()
|
||
|
|
||
|
|
||
|
DefaultResolver = AsyncResolver if aiodns_default else ThreadedResolver
|