Update types for h11 v0.14 (#579)

* Update setup.py

Allow for h11 V. 013. Facilitates installation alongside latest version of Uvicorn.

* Bump h11 pin to 0.14

* Remove reassignment of `event` to prevent type failure

* Add an explicit check for `None` in `_send_event`

This also reverted commit f9a9847
which was dropped during rebase with the `master` branch.

We probably do not want to suggest that passing `None` to
the `write` function is proper. The short circuit there (return on
empty buffer) should be targeted to an empty byte array.

* Replace h11 event with new base class type; add stubs for PAUSED handling

* Lint; add cast for return type

* apply unasync

* do not attempt to handle paused in _receive_event

* Bump h11 upper bound to 0.15

* Update types to support h11 0.14.0

* Bump minimum h11 requirement to 0.13

0.12 does not define `h11.Event`

* Update `_send_event` to narrow accepted types

* Lint

Co-authored-by: Francis Secada <francis.secada@gmail.com>
Co-authored-by: Tom Christie <tom@tomchristie.com>
Co-authored-by: Thomas Grainger <tagrain@gmail.com>
Co-authored-by: Marcelo Trylesinski <marcelotryle@gmail.com>

httpcore/_async/http11.py

@@ -1,7 +1,16 @@
 import enum
 import time
 from types import TracebackType
-from typing import AsyncIterable, AsyncIterator, List, Optional, Tuple, Type, Union
+from typing import (
+    AsyncIterable,
+    AsyncIterator,
+    List,
+    Optional,
+    Tuple,
+    Type,
+    Union,
+    cast,
+)
 
 import h11
 
@@ -17,13 +26,11 @@
 from ..backends.base import AsyncNetworkStream
 from .interfaces import AsyncConnectionInterface
 
-H11Event = Union[
+# A subset of `h11.Event` types supported by `_send_event`
+H11SendEvent = Union[
     h11.Request,
-    h11.Response,
-    h11.InformationalResponse,
     h11.Data,
     h11.EndOfMessage,
-    h11.ConnectionClosed,
 ]
 
 
@@ -127,14 +134,14 @@ async def _send_request_body(self, request: Request) -> None:
             event = h11.Data(data=chunk)
             await self._send_event(event, timeout=timeout)
 
-        event = h11.EndOfMessage()
-        await self._send_event(event, timeout=timeout)
+        await self._send_event(h11.EndOfMessage(), timeout=timeout)
 
     async def _send_event(
-        self, event: H11Event, timeout: Optional[float] = None
+        self, event: h11.Event, timeout: Optional[float] = None
     ) -> None:
         bytes_to_send = self._h11_state.send(event)
-        await self._network_stream.write(bytes_to_send, timeout=timeout)
+        if bytes_to_send is not None:
+            await self._network_stream.write(bytes_to_send, timeout=timeout)
 
     # Receiving the response...
 
@@ -168,7 +175,9 @@ async def _receive_response_body(self, request: Request) -> AsyncIterator[bytes]
             elif isinstance(event, (h11.EndOfMessage, h11.PAUSED)):
                 break
 
-    async def _receive_event(self, timeout: Optional[float] = None) -> H11Event:
+    async def _receive_event(
+        self, timeout: Optional[float] = None
+    ) -> Union[h11.Event, Type[h11.PAUSED]]:
         while True:
             with map_exceptions({h11.RemoteProtocolError: RemoteProtocolError}):
                 event = self._h11_state.next_event()
@@ -192,7 +201,8 @@ async def _receive_event(self, timeout: Optional[float] = None) -> H11Event:
 
                 self._h11_state.receive_data(data)
             else:
-                return event
+                # mypy fails to narrow the type in the above if statement above
+                return cast(Union[h11.Event, Type[h11.PAUSED]], event)
 
     async def _response_closed(self) -> None:
         async with self._state_lock:

httpcore/_sync/http11.py

@@ -1,7 +1,16 @@
 import enum
 import time
 from types import TracebackType
-from typing import Iterable, Iterator, List, Optional, Tuple, Type, Union
+from typing import (
+    Iterable,
+    Iterator,
+    List,
+    Optional,
+    Tuple,
+    Type,
+    Union,
+    cast,
+)
 
 import h11
 
@@ -17,13 +26,11 @@
 from ..backends.base import NetworkStream
 from .interfaces import ConnectionInterface
 
-H11Event = Union[
+# A subset of `h11.Event` types supported by `_send_event`
+H11SendEvent = Union[
     h11.Request,
-    h11.Response,
-    h11.InformationalResponse,
     h11.Data,
     h11.EndOfMessage,
-    h11.ConnectionClosed,
 ]
 
 
@@ -127,14 +134,14 @@ def _send_request_body(self, request: Request) -> None:
             event = h11.Data(data=chunk)
             self._send_event(event, timeout=timeout)
 
-        event = h11.EndOfMessage()
-        self._send_event(event, timeout=timeout)
+        self._send_event(h11.EndOfMessage(), timeout=timeout)
 
     def _send_event(
-        self, event: H11Event, timeout: Optional[float] = None
+        self, event: h11.Event, timeout: Optional[float] = None
     ) -> None:
         bytes_to_send = self._h11_state.send(event)
-        self._network_stream.write(bytes_to_send, timeout=timeout)
+        if bytes_to_send is not None:
+            self._network_stream.write(bytes_to_send, timeout=timeout)
 
     # Receiving the response...
 
@@ -168,7 +175,9 @@ def _receive_response_body(self, request: Request) -> Iterator[bytes]:
             elif isinstance(event, (h11.EndOfMessage, h11.PAUSED)):
                 break
 
-    def _receive_event(self, timeout: Optional[float] = None) -> H11Event:
+    def _receive_event(
+        self, timeout: Optional[float] = None
+    ) -> Union[h11.Event, Type[h11.PAUSED]]:
         while True:
             with map_exceptions({h11.RemoteProtocolError: RemoteProtocolError}):
                 event = self._h11_state.next_event()
@@ -192,7 +201,8 @@ def _receive_event(self, timeout: Optional[float] = None) -> H11Event:
 
                 self._h11_state.receive_data(data)
             else:
-                return event
+                # mypy fails to narrow the type in the above if statement above
+                return cast(Union[h11.Event, Type[h11.PAUSED]], event)
 
     def _response_closed(self) -> None:
         with self._state_lock:

setup.py

@@ -54,7 +54,7 @@ def get_packages(package):
     include_package_data=True,
     zip_safe=False,
     install_requires=[
-        "h11>=0.11,<0.13",
+        "h11>=0.13,<0.15",
         "sniffio==1.*",
         "anyio==3.*",
         "certifi",