Fix 0.30.4 issue with connection close header (#2408)

* fix server waiting state with connection close header

* added test case for closing post connection with connection header

* removed post without body test case with connection close header

* removed unnecessary line removal

tests/protocols/test_http.py

@@ -61,6 +61,18 @@
 
 CONNECTION_CLOSE_REQUEST = b"\r\n".join([b"GET / HTTP/1.1", b"Host: example.org", b"Connection: close", b"", b""])
 
+CONNECTION_CLOSE_POST_REQUEST = b"\r\n".join(
+    [
+        b"POST / HTTP/1.1",
+        b"Host: example.org",
+        b"Connection: close",
+        b"Content-Type: application/json",
+        b"Content-Length: 18",
+        b"",
+        b"{'hello': 'world'}",
+    ]
+)
+
 REQUEST_AFTER_CONNECTION_CLOSE = b"\r\n".join(
     [
         b"GET / HTTP/1.1",
@@ -1011,6 +1023,25 @@ async def test_close_connection_with_multiple_requests(http_protocol_cls: HTTPPr
     assert b"connection: close" in protocol.transport.buffer.lower()
 
 
+async def test_close_connection_with_post_request(http_protocol_cls: HTTPProtocol):
+    async def app(scope: Scope, receive: ASGIReceiveCallable, send: ASGISendCallable):
+        body = b""
+        more_body = True
+        while more_body:
+            message = await receive()
+            assert message["type"] == "http.request"
+            body += message.get("body", b"")
+            more_body = message.get("more_body", False)
+        response = Response(b"Body: " + body, media_type="text/plain")
+        await response(scope, receive, send)
+
+    protocol = get_connected_protocol(app, http_protocol_cls)
+    protocol.data_received(CONNECTION_CLOSE_POST_REQUEST)
+    await protocol.loop.run_one()
+    assert b"HTTP/1.1 200 OK" in protocol.transport.buffer
+    assert b"Body: {'hello': 'world'}" in protocol.transport.buffer
+
+
 async def test_iterator_headers(http_protocol_cls: HTTPProtocol):
     async def app(scope: Scope, receive: ASGIReceiveCallable, send: ASGISendCallable):
         headers = iter([(b"x-test-header", b"test value")])

uvicorn/protocols/http/h11_impl.py

@@ -259,10 +259,10 @@ def handle_events(self) -> None:
                     self.transport.resume_reading()
                     self.conn.start_next_cycle()
                     continue
-                if self.conn.their_state == h11.MUST_CLOSE:
-                    break
                 self.cycle.more_body = False
                 self.cycle.message_event.set()
+                if self.conn.their_state == h11.MUST_CLOSE:
+                    break
 
     def handle_websocket_upgrade(self, event: h11.Request) -> None:
         if self.logger.level <= TRACE_LOG_LEVEL:  # pragma: full coverage