Fix AWSCRTHTTPClient request bodies for HTTP/1.1 connections

packages/smithy-http/.changes/next-release/smithy-http-bugfix-fe459b1f8f194ffbb05840170a508e5a.json

@@ -0,0 +1,4 @@
+{
+  "type": "bugfix",
+  "description": "Fixed `AWSCRTHTTPClient` to send HTTP/1.1 request bodies via `body_stream` instead of the HTTP/2-only `request_body_generator`."
+}

packages/smithy-http/src/smithy_http/aio/crt.py

@@ -6,6 +6,7 @@
 from copy import deepcopy
 from dataclasses import dataclass
 from inspect import iscoroutinefunction
+from io import BytesIO
 from typing import TYPE_CHECKING, Any
 
 from awscrt.exceptions import AwsCrtError
@@ -36,6 +37,7 @@
 from smithy_core import interfaces as core_interfaces
 from smithy_core.aio import interfaces as core_aio_interfaces
 from smithy_core.aio.types import AsyncBytesReader
+from smithy_core.aio.utils import read_streaming_blob_async
 from smithy_core.exceptions import MissingDependencyError
 
 from .. import Field, Fields
@@ -175,13 +177,18 @@ async def send(
             crt_request = self._marshal_request(request)
             connection = await self._get_connection(request.destination)
 
-            # Convert body to async iterator for request_body_generator
-            body_generator = self._create_body_generator(request.body)
-
-            crt_stream = connection.request(
-                crt_request,
-                request_body_generator=body_generator,
-            )
+            # request_body_generator is HTTP/2-only in CRT; HTTP/1.1 must use body_stream
+            if connection.version == crt_http.HttpVersion.Http2:
+                crt_stream = connection.request(
+                    crt_request,
+                    request_body_generator=self._create_body_generator(request.body),
+                )
+            else:
+                if (
+                    body_stream := await self._create_body_stream(request.body)
+                ) is not None:
+                    crt_request.body_stream = body_stream
+                crt_stream = connection.request(crt_request)
 
             return await self._await_response(crt_stream)
         except AwsCrtError as e:
@@ -308,6 +315,15 @@ def _marshal_request(
         )
         return crt_request
 
+    async def _create_body_stream(
+        self, body: core_aio_interfaces.StreamingBlob
+    ) -> core_interfaces.BytesReader | None:
+        """Convert various body types to a bytes reader for CRT HTTP/1.1."""
+        if core_interfaces.is_bytes_reader(body):
+            return body
+        buffered = await read_streaming_blob_async(body)
+        return BytesIO(buffered) if buffered else None
+
     async def _create_body_generator(
         self, body: core_aio_interfaces.StreamingBlob
     ) -> AsyncGenerator[bytes, None]:

packages/smithy-http/tests/unit/aio/test_crt.py

@@ -66,6 +66,69 @@ async def test_port_included_in_host_header(host: str, expected: str) -> None:
     assert crt_request.headers.get("host") == expected  # type: ignore
 
 
+async def test_send_http1_uses_body_stream() -> None:
+    """Test HTTP/1.1 requests use the CRT body stream."""
+    client = AWSCRTHTTPClient()
+    request = HTTPRequest(
+        method="POST",
+        destination=URI(scheme="https", host="example.com", path="/"),
+        body=AsyncBytesReader(b"Action=Test&Version=2020-01-08"),
+        fields=Fields(),
+    )
+    mock_stream = Mock()
+    mock_response = Mock()
+    mock_connection = Mock()
+    mock_connection.version = crt_http.HttpVersion.Http1_1
+    mock_connection.request = Mock(return_value=mock_stream)
+
+    with (
+        patch.object(
+            client, "_get_connection", AsyncMock(return_value=mock_connection)
+        ),
+        patch.object(client, "_await_response", AsyncMock(return_value=mock_response)),
+    ):
+        actual = await client.send(request)
+
+    assert actual is mock_response
+    mock_connection.request.assert_called_once()
+    assert "request_body_generator" not in mock_connection.request.call_args.kwargs
+    crt_request = mock_connection.request.call_args.args[0]
+    assert crt_request.body_stream is not None
+
+
+async def test_send_http2_uses_body_generator() -> None:
+    """Test HTTP/2 requests use the CRT body generator."""
+    client = AWSCRTHTTPClient()
+    request = HTTPRequest(
+        method="POST",
+        destination=URI(scheme="https", host="example.com", path="/"),
+        body=AsyncBytesReader(b"Action=Test&Version=2020-01-08"),
+        fields=Fields(),
+    )
+    mock_stream = Mock()
+    mock_response = Mock()
+    mock_connection = Mock()
+    mock_connection.version = crt_http.HttpVersion.Http2
+    mock_connection.request = Mock(return_value=mock_stream)
+
+    with (
+        patch.object(
+            client, "_get_connection", AsyncMock(return_value=mock_connection)
+        ),
+        patch.object(client, "_await_response", AsyncMock(return_value=mock_response)),
+    ):
+        actual = await client.send(request)
+
+    assert actual is mock_response
+    mock_connection.request.assert_called_once()
+    crt_request = mock_connection.request.call_args.args[0]
+    body_generator = mock_connection.request.call_args.kwargs["request_body_generator"]
+    assert crt_request.body_stream is None
+    assert [chunk async for chunk in body_generator] == [
+        b"Action=Test&Version=2020-01-08"
+    ]
+
+
 async def test_body_generator_bytes() -> None:
     """Test body generator with bytes input."""
     client = AWSCRTHTTPClient()
@@ -191,6 +254,53 @@ async def test_body_generator_empty_bytes() -> None:
     assert chunks == [b""]
 
 
+async def test_body_stream_bytes() -> None:
+    """Test body stream with bytes input."""
+    client = AWSCRTHTTPClient()
+
+    body_stream = await client._create_body_stream(b"Hello, World!")
+
+    assert body_stream is not None
+    assert body_stream.read() == b"Hello, World!"
+
+
+async def test_body_stream_bytesio() -> None:
+    """Test body stream with BytesIO."""
+    client = AWSCRTHTTPClient()
+    body = BytesIO(b"data from BytesIO")
+
+    body_stream = await client._create_body_stream(body)
+
+    assert body_stream is not None
+    assert body_stream is body
+    assert body_stream.read() == b"data from BytesIO"
+
+
+async def test_body_stream_async_iterable() -> None:
+    """Test body stream with custom AsyncIterable."""
+
+    async def custom_generator() -> AsyncIterator[bytes]:
+        yield b"chunk1"
+        yield b"chunk2"
+        yield b"chunk3"
+
+    client = AWSCRTHTTPClient()
+
+    body_stream = await client._create_body_stream(custom_generator())
+
+    assert body_stream is not None
+    assert body_stream.read() == b"chunk1chunk2chunk3"
+
+
+async def test_body_stream_empty_bytes() -> None:
+    """Test body stream with empty bytes."""
+    client = AWSCRTHTTPClient()
+
+    body_stream = await client._create_body_stream(b"")
+
+    assert body_stream is None
+
+
 async def test_build_connection_http() -> None:
     """Test building HTTP connection."""
     client = AWSCRTHTTPClient()