Add HTTP3 support

httpcore/__init__.py

@@ -3,6 +3,7 @@
  AsyncConnectionInterface,
  AsyncConnectionPool,
  AsyncHTTP2Connection,
+ AsyncHTTP3Connection,
  AsyncHTTP11Connection,
  AsyncHTTPConnection,
  AsyncHTTPProxy,
@@ -40,6 +41,7 @@
  ConnectionInterface,
  ConnectionPool,
  HTTP2Connection,
+ HTTP3Connection,
  HTTP11Connection,
  HTTPConnection,
  HTTPProxy,
@@ -85,6 +87,7 @@ def __init__(self, *args, **kwargs): # type: ignore
  "AsyncHTTPProxy",
  "AsyncHTTP11Connection",
  "AsyncHTTP2Connection",
+ "AsyncHTTP3Connection",
  "AsyncConnectionInterface",
  "AsyncSOCKSProxy",
  # sync
@@ -93,6 +96,7 @@ def __init__(self, *args, **kwargs): # type: ignore
  "HTTPProxy",
  "HTTP11Connection",
  "HTTP2Connection",
+ "HTTP3Connection",
  "ConnectionInterface",
  "SOCKSProxy",
  # network backends, implementations

httpcore/_async/__init__.py

@@ -16,6 +16,18 @@ def __init__(self, *args, **kwargs) -> None: # type: ignore
  )
 
 
+try:
+ from .http3 import AsyncHTTP3Connection
+except ImportError: # pragma: nocover
+
+ class AsyncHTTP3Connection: # type: ignore
+ def __init__(self, *args, **kwargs) -> None: # type: ignore
+ raise RuntimeError(
+ "Attempted to use http3 support, but the `aioquic` package is not "
+ "installed. Use 'pip install httpcore[http3]'."
+ )
+
+
 try:
  from .socks_proxy import AsyncSOCKSProxy
 except ImportError: # pragma: nocover
@@ -34,6 +46,7 @@ def __init__(self, *args, **kwargs) -> None: # type: ignore
  "AsyncHTTPProxy",
  "AsyncHTTP11Connection",
  "AsyncHTTP2Connection",
+ "AsyncHTTP3Connection",
  "AsyncConnectionInterface",
  "AsyncSOCKSProxy",
 ]

httpcore/_async/connection.py

@@ -41,6 +41,7 @@ def __init__(
  keepalive_expiry: Optional[float] = None,
  http1: bool = True,
  http2: bool = False,
+ http3: bool = False,
  retries: int = 0,
  local_address: Optional[str] = None,
  uds: Optional[str] = None,
@@ -52,6 +53,7 @@ def __init__(
  self._keepalive_expiry = keepalive_expiry
  self._http1 = http1
  self._http2 = http2
+ self._http3 = http3
  self._retries = retries
  self._local_address = local_address
  self._uds = uds
@@ -80,7 +82,18 @@ async def handle_async_request(self, request: Request) -> Response:
  ssl_object is not None
  and ssl_object.selected_alpn_protocol() == "h2"
  )
- if http2_negotiated or (self._http2 and not self._http1):
+ if self._http3 and not (
+ self._http1 or self._http2
+ ): # pragma: no cover
+ from .http3 import AsyncHTTP3Connection
+
+ stream = await self._connect_http3(request)
+ self._connection = AsyncHTTP3Connection(
+ origin=self._origin,
+ stream=stream,
+ keepalive_expiry=self._keepalive_expiry,
+ )
+ elif http2_negotiated or (self._http2 and not self._http1):
  from .http2 import AsyncHTTP2Connection
 
  self._connection = AsyncHTTP2Connection(
@@ -162,6 +175,30 @@ async def _connect(self, request: Request) -> AsyncNetworkStream:
  async with Trace("retry", logger, request, kwargs) as trace:
  await self._network_backend.sleep(delay)
 
+ async def _connect_http3(
+ self, request: Request
+ ) -> AsyncNetworkStream: # pragma: nocover
+ retries_left = self._retries
+ delays = exponential_backoff(factor=RETRIES_BACKOFF_FACTOR)
+
+ while True:
+ try:
+ kwargs = {
+ "host": self._origin.host.decode("ascii"),
+ "port": self._origin.port,
+ }
+ async with Trace("connect_udp", logger, request, kwargs) as trace:
+ stream = await self._network_backend.connect_udp(**kwargs) # type: ignore
+ trace.return_value = stream
+ return stream
+ except (ConnectError, ConnectTimeout):
+ if retries_left <= 0:
+ raise
+ retries_left -= 1
+ delay = next(delays)
+ async with Trace("retry", logger, request, kwargs) as trace:
+ await self._network_backend.sleep(delay)
+
  def can_handle_request(self, origin: Origin) -> bool:
  return origin == self._origin
 

httpcore/_async/connection_pool.py

@@ -53,6 +53,7 @@ def __init__(
  keepalive_expiry: Optional[float] = None,
  http1: bool = True,
  http2: bool = False,
+ http3: bool = False,
  retries: int = 0,
  local_address: Optional[str] = None,
  uds: Optional[str] = None,
@@ -77,6 +78,8 @@ def __init__(
  by the connection pool. Defaults to True.
  http2: A boolean indicating if HTTP/2 requests should be supported by
  the connection pool. Defaults to False.
+ http3: A boolean indicating if HTTP/3 requests should be supported by
+ the connection pool. Defaults to False.
  retries: The maximum number of retries when trying to establish a
  connection.
  local_address: Local address to connect from. Can also be used to connect
@@ -105,6 +108,7 @@ def __init__(
  self._keepalive_expiry = keepalive_expiry
  self._http1 = http1
  self._http2 = http2
+ self._http3 = http3
  self._retries = retries
  self._local_address = local_address
  self._uds = uds
@@ -131,6 +135,7 @@ def create_connection(self, origin: Origin) -> AsyncConnectionInterface:
  keepalive_expiry=self._keepalive_expiry,
  http1=self._http1,
  http2=self._http2,
+ http3=self._http3,
  retries=self._retries,
  local_address=self._local_address,
  uds=self._uds,