# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
"""trio async I/O library query support"""
import socket
import trio
import trio.socket # type: ignore
import dns._asyncbackend
import dns._features
import dns.exception
import dns.inet
if not dns._features.have("trio"):
raise ImportError("trio not found or too old")
def _maybe_timeout(timeout):
if timeout is not None:
return trio.move_on_after(timeout)
else:
return dns._asyncbackend.NullContext()
# for brevity
_lltuple = dns.inet.low_level_address_tuple
# pylint: disable=redefined-outer-name
class DatagramSocket(dns._asyncbackend.DatagramSocket):
def __init__(self, sock):
super().__init__(sock.family, socket.SOCK_DGRAM)
self.socket = sock
async def sendto(self, what, destination, timeout):
with _maybe_timeout(timeout):
if destination is None:
return await self.socket.send(what)
else:
return await self.socket.sendto(what, destination)
raise dns.exception.Timeout(
timeout=timeout
) # pragma: no cover lgtm[py/unreachable-statement]
async def recvfrom(self, size, timeout):
with _maybe_timeout(timeout):
return await self.socket.recvfrom(size)
raise dns.exception.Timeout(timeout=timeout) # lgtm[py/unreachable-statement]
async def close(self):
self.socket.close()
async def getpeername(self):
return self.socket.getpeername()
async def getsockname(self):
return self.socket.getsockname()
async def getpeercert(self, timeout):
raise NotImplementedError
class StreamSocket(dns._asyncbackend.StreamSocket):
def __init__(self, family, stream, tls=False):
super().__init__(family, socket.SOCK_STREAM)
self.stream = stream
self.tls = tls
async def sendall(self, what, timeout):
with _maybe_timeout(timeout):
return await self.stream.send_all(what)
raise dns.exception.Timeout(timeout=timeout) # lgtm[py/unreachable-statement]
async def recv(self, size, timeout):
with _maybe_timeout(timeout):
return await self.stream.receive_some(size)
raise dns.exception.Timeout(timeout=timeout) # lgtm[py/unreachable-statement]
async def close(self):
await self.stream.aclose()
async def getpeername(self):
if self.tls:
return self.stream.transport_stream.socket.getpeername()
else:
return self.stream.socket.getpeername()
async def getsockname(self):
if self.tls:
return self.stream.transport_stream.socket.getsockname()
else:
return self.stream.socket.getsockname()
async def getpeercert(self, timeout):
if self.tls:
with _maybe_timeout(timeout):
await self.stream.do_handshake()
return self.stream.getpeercert()
else:
raise NotImplementedError
if dns._features.have("doh"):
import httpcore
import httpcore._backends.trio
import httpx
_CoreAsyncNetworkBackend = httpcore.AsyncNetworkBackend
_CoreTrioStream = httpcore._backends.trio.TrioStream
from dns.query import _compute_times, _expiration_for_this_attempt, _remaining
class _NetworkBackend(_CoreAsyncNetworkBackend):
def __init__(self, resolver, local_port, bootstrap_address, family):
super().__init__()
self._local_port = local_port
self._resolver = resolver
self._bootstrap_address = bootstrap_address
self._family = family
async def connect_tcp(
self, host, port, timeout, local_address, socket_options=None
): # pylint: disable=signature-differs
addresses = []
_, expiration = _compute_times(timeout)
if dns.inet.is_address(host):
addresses.append(host)
elif self._bootstrap_address is not None:
addresses.append(self._bootstrap_address)
else:
timeout = _remaining(expiration)
family = self._family
if local_address:
family = dns.inet.af_for_address(local_address)
answers = await self._resolver.resolve_name(
host, family=family, lifetime=timeout
)
addresses = answers.addresses()
for address in addresses:
try:
af = dns.inet.af_for_address(address)
if local_address is not None or self._local_port != 0:
source = (local_address, self._local_port)
else:
source = None
destination = (address, port)
attempt_expiration = _expiration_for_this_attempt(2.0, expiration)
timeout = _remaining(attempt_expiration)
sock = await Backend().make_socket(
af, socket.SOCK_STREAM, 0, source, destination, timeout
)
return _CoreTrioStream(sock.stream)
except Exception:
continue
raise httpcore.ConnectError
async def connect_unix_socket(
self, path, timeout, socket_options=None
): # pylint: disable=signature-differs
raise NotImplementedError
async def sleep(self, seconds): # pylint: disable=signature-differs
await trio.sleep(seconds)
class _HTTPTransport(httpx.AsyncHTTPTransport):
def __init__(
self,
*args,
local_port=0,
bootstrap_address=None,
resolver=None,
family=socket.AF_UNSPEC,
**kwargs,
):
if resolver is None and bootstrap_address is None:
# pylint: disable=import-outside-toplevel,redefined-outer-name
import dns.asyncresolver
resolver = dns.asyncresolver.Resolver()
super().__init__(*args, **kwargs)
self._pool._network_backend = _NetworkBackend(
resolver, local_port, bootstrap_address, family
)
else:
_HTTPTransport = dns._asyncbackend.NullTransport # type: ignore
class Backend(dns._asyncbackend.Backend):
def name(self):
return "trio"
async def make_socket(
self,
af,
socktype,
proto=0,
source=None,
destination=None,
timeout=None,
ssl_context=None,
server_hostname=None,
):
s = trio.socket.socket(af, socktype, proto)
stream = None
try:
if source:
await s.bind(_lltuple(source, af))
if socktype == socket.SOCK_STREAM or destination is not None:
connected = False
with _maybe_timeout(timeout):
await s.connect(_lltuple(destination, af))
connected = True
if not connected:
raise dns.exception.Timeout(
timeout=timeout
) # lgtm[py/unreachable-statement]
except Exception: # pragma: no cover
s.close()
raise
if socktype == socket.SOCK_DGRAM:
return DatagramSocket(s)
elif socktype == socket.SOCK_STREAM:
stream = trio.SocketStream(s)
tls = False
if ssl_context:
tls = True
try:
stream = trio.SSLStream(
stream, ssl_context, server_hostname=server_hostname
)
except Exception: # pragma: no cover
await stream.aclose()
raise
return StreamSocket(af, stream, tls)
raise NotImplementedError(
"unsupported socket " + f"type {socktype}"
) # pragma: no cover
async def sleep(self, interval):
await trio.sleep(interval)
def get_transport_class(self):
return _HTTPTransport
async def wait_for(self, awaitable, timeout):
with _maybe_timeout(timeout):
return await awaitable
raise dns.exception.Timeout(
timeout=timeout
) # pragma: no cover lgtm[py/unreachable-statement]
