Deprecating aws_iam_streamablehttp_client

Author: andreyyoshuamanik

CHANGELOG.md

@@ -5,6 +5,22 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## v1.2.0 (2026-01-08)
+
+### Added
+
+- New `aws_iam_streamable_http_client` function to replace deprecated `aws_iam_streamablehttp_client`
+
+### Changed
+
+- Updated minimum `fastmcp` version to 2.14.2 to support `streamable_http_client` function from mcp>=1.25.0
+
+### Deprecated
+
+- `aws_iam_streamablehttp_client` is now deprecated in favor of `aws_iam_streamable_http_client` 
+  to align with upstream MCP package naming conventions. The old function will be removed in version 2.0.0.
+- `sse_read_timeout` parameter in `aws_iam_streamable_http_client` is deprecated and will be removed in version 2.0.0
+
 ## v1.1.5 (2025-12-15)
 
 ### Fix

mcp_proxy_for_aws/client.py

@@ -13,12 +13,14 @@
 # limitations under the License.
 
 import boto3
+import httpx
 import logging
+import warnings
 from anyio.streams.memory import MemoryObjectReceiveStream, MemoryObjectSendStream
 from botocore.credentials import Credentials
 from contextlib import _AsyncGeneratorContextManager
 from datetime import timedelta
-from mcp.client.streamable_http import GetSessionIdCallback, streamablehttp_client
+from mcp.client.streamable_http import GetSessionIdCallback, streamable_http_client
 from mcp.shared._httpx_utils import McpHttpClientFactory, create_mcp_http_client
 from mcp.shared.message import SessionMessage
 from mcp_proxy_for_aws.sigv4_helper import SigV4HTTPXAuth
@@ -28,7 +30,7 @@
 logger = logging.getLogger(__name__)
 
 
-def aws_iam_streamablehttp_client(
+def aws_iam_streamable_http_client(
     endpoint: str,
     aws_service: str,
     aws_region: Optional[str] = None,
@@ -60,7 +62,7 @@ def aws_iam_streamablehttp_client(
         credentials: Optional AWS credentials from boto3/botocore. If provided, takes precedence over aws_profile.
         headers: Optional additional HTTP headers to include in requests.
         timeout: Request timeout in seconds or timedelta object. Defaults to 30 seconds.
-        sse_read_timeout: Server-sent events read timeout in seconds or timedelta object.
+        sse_read_timeout: Deprecated. This parameter is no longer used and will be removed in version 2.0.0.
         terminate_on_close: Whether to terminate the connection on close.
         httpx_client_factory: Factory function for creating HTTPX clients.
 
@@ -71,7 +73,7 @@ def aws_iam_streamablehttp_client(
             - get_session_id: Callback function to retrieve the current session ID
 
     Example:
-        async with aws_iam_mcp_client(
+        async with aws_iam_streamable_http_client(
             endpoint="https://example.com/mcp",
             aws_service="bedrock-agentcore",
             aws_region="us-west-2"
@@ -81,6 +83,13 @@ def aws_iam_streamablehttp_client(
     """
     logger.debug('Preparing AWS IAM MCP client for endpoint: %s', endpoint)
 
+    # Warn if sse_read_timeout is set to a non-default value
+    if sse_read_timeout != 60 * 5:
+        logger.warning(
+            'sse_read_timeout parameter is deprecated and will be removed in version 2.0.0. '
+            'The value is ignored in the current implementation.'
+        )
+
     if credentials is not None:
         creds = credentials
         region = aws_region
@@ -113,13 +122,74 @@ def aws_iam_streamablehttp_client(
     # Create a SigV4 authentication handler with AWS credentials
     auth = SigV4HTTPXAuth(creds, aws_service, region)
 
+    # Convert timeout to httpx.Timeout if it's a number or timedelta
+    httpx_timeout = None
+    if timeout is not None:
+        if isinstance(timeout, (int, float)):
+            httpx_timeout = httpx.Timeout(timeout)
+        elif isinstance(timeout, timedelta):
+            httpx_timeout = httpx.Timeout(timeout.total_seconds())
+        else:
+            httpx_timeout = timeout
+
+    # Create HTTP client using the factory with authentication and custom headers
+    http_client = httpx_client_factory(
+        auth=auth,
+        timeout=httpx_timeout,
+        headers=headers,
+    )
+
     # Return the streamable HTTP client context manager with AWS IAM authentication
-    return streamablehttp_client(
+    return streamable_http_client(
         url=endpoint,
+        http_client=http_client,
+        terminate_on_close=terminate_on_close,
+    )
+
+
+def aws_iam_streamablehttp_client(
+    endpoint: str,
+    aws_service: str,
+    aws_region: Optional[str] = None,
+    aws_profile: Optional[str] = None,
+    credentials: Optional[Credentials] = None,
+    headers: Optional[dict[str, str]] = None,
+    timeout: float | timedelta = 30,
+    sse_read_timeout: float | timedelta = 60 * 5,
+    terminate_on_close: bool = True,
+    httpx_client_factory: McpHttpClientFactory = create_mcp_http_client,
+) -> _AsyncGeneratorContextManager[
+    tuple[
+        MemoryObjectReceiveStream[SessionMessage | Exception],
+        MemoryObjectSendStream[SessionMessage],
+        GetSessionIdCallback,
+    ],
+    None,
+]:
+    """Create an AWS IAM-authenticated MCP streamable HTTP client.
+
+    .. deprecated:: 1.2.0
+        Use :func:`aws_iam_streamable_http_client` instead.
+        This function will be removed in version 2.0.0.
+
+    This is a deprecated alias for aws_iam_streamable_http_client.
+    Please update your code to use aws_iam_streamable_http_client instead.
+    """
+    warnings.warn(
+        "aws_iam_streamablehttp_client is deprecated and will be removed in version 2.0.0. "
+        "Use aws_iam_streamable_http_client instead.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
+    return aws_iam_streamable_http_client(
+        endpoint=endpoint,
+        aws_service=aws_service,
+        aws_region=aws_region,
+        aws_profile=aws_profile,
+        credentials=credentials,
         headers=headers,
         timeout=timeout,
         sse_read_timeout=sse_read_timeout,
         terminate_on_close=terminate_on_close,
         httpx_client_factory=httpx_client_factory,
-        auth=auth,
     )

mcp_proxy_for_aws/utils.py

@@ -57,6 +57,7 @@ def client_factory(
         headers: Optional[Dict[str, str]] = None,
         timeout: Optional[httpx.Timeout] = None,
         auth: Optional[httpx.Auth] = None,
+        **kwargs,  # Accept additional parameters from fastmcp (e.g., follow_redirects)
     ) -> httpx.AsyncClient:
         return create_sigv4_client(
             service=service,

pyproject.toml

@@ -10,13 +10,13 @@ members = [
 name = "mcp-proxy-for-aws"
 
 # NOTE: "Patch"=9223372036854775807 bumps next release to zero.
-version = "1.1.5"
+version = "1.2.0"
 
 description = "MCP Proxy for AWS"
 readme = "README.md"
 requires-python = ">=3.10,<3.14"
 dependencies = [
-    "fastmcp (>=2.13.1,<2.14.1)",
+    "fastmcp>=2.14.2",
     "boto3>=1.41.0",
     "botocore[crt]>=1.41.0",
 ]

tests/integ/mcp/simple_mcp_client.py

@@ -69,8 +69,11 @@ def _build_mcp_config(endpoint: str, region_name: str, metadata: Optional[Dict[s
         'AWS_REGION': region_name,
         'AWS_ACCESS_KEY_ID': credentials.access_key,
         'AWS_SECRET_ACCESS_KEY': credentials.secret_key,
-        'AWS_SESSION_TOKEN': credentials.token,
     }
+    
+    # Only include AWS_SESSION_TOKEN if it's not None (e.g., for temporary credentials)
+    if credentials.token:
+        environment_variables['AWS_SESSION_TOKEN'] = credentials.token
 
     args = _build_args(endpoint, region_name, metadata)
 

tests/unit/test_client.py

@@ -60,7 +60,7 @@ async def test_boto3_session_parameters(
     mock_read, mock_write, mock_get_session = mock_streams
 
     with patch('boto3.Session', return_value=mock_session) as mock_boto:
-        with patch('mcp_proxy_for_aws.client.streamablehttp_client') as mock_stream_client:
+        with patch('mcp_proxy_for_aws.client.streamable_http_client') as mock_stream_client:
             mock_stream_client.return_value.__aenter__ = AsyncMock(
                 return_value=(mock_read, mock_write, mock_get_session)
             )
@@ -94,9 +94,14 @@ async def test_sigv4_auth_is_created_and_used(mock_session, mock_streams, servic
 
     with patch('boto3.Session', return_value=mock_session):
         with patch('mcp_proxy_for_aws.client.SigV4HTTPXAuth') as mock_auth_cls:
-            with patch('mcp_proxy_for_aws.client.streamablehttp_client') as mock_stream_client:
+            with patch('mcp_proxy_for_aws.client.streamable_http_client') as mock_stream_client:
                 mock_auth = Mock()
                 mock_auth_cls.return_value = mock_auth
+                
+                # Mock the factory to capture its calls
+                mock_http_client = Mock()
+                mock_factory = Mock(return_value=mock_http_client)
+                
                 mock_stream_client.return_value.__aenter__ = AsyncMock(
                     return_value=(mock_read, mock_write, mock_get_session)
                 )
@@ -106,17 +111,22 @@ async def test_sigv4_auth_is_created_and_used(mock_session, mock_streams, servic
                     endpoint='https://test.example.com/mcp',
                     aws_service=service_name,
                     aws_region=region,
+                    httpx_client_factory=mock_factory,
                 ):
                     pass
 
                 mock_auth_cls.assert_called_once_with(
                     # Auth should be constructed with the resolved credentials, service, and region,
-                    # and passed into the streamable client.
+                    # and passed to the httpx client factory.
                     mock_session.get_credentials.return_value,
                     service_name,
                     region,
                 )
-                assert mock_stream_client.call_args[1]['auth'] is mock_auth
+                # Check that factory was called with auth
+                assert mock_factory.called
+                assert mock_factory.call_args[1]['auth'] is mock_auth
+                # Check that http_client was passed to streamable_http_client
+                assert mock_stream_client.call_args[1]['http_client'] is mock_http_client
 
 
 @pytest.mark.asyncio
@@ -137,7 +147,10 @@ async def test_streamable_client_parameters(
     mock_read, mock_write, mock_get_session = mock_streams
 
     with patch('boto3.Session', return_value=mock_session):
-        with patch('mcp_proxy_for_aws.client.streamablehttp_client') as mock_stream_client:
+        with patch('mcp_proxy_for_aws.client.streamable_http_client') as mock_stream_client:
+            mock_http_client = Mock()
+            mock_factory = Mock(return_value=mock_http_client)
+            
             mock_stream_client.return_value.__aenter__ = AsyncMock(
                 return_value=(mock_read, mock_write, mock_get_session)
             )
@@ -150,16 +163,30 @@ async def test_streamable_client_parameters(
                 timeout=timeout_value,
                 sse_read_timeout=sse_value,
                 terminate_on_close=terminate_value,
+                httpx_client_factory=mock_factory,
             ):
                 pass
 
-            call_kwargs = mock_stream_client.call_args[1]
-            # Confirm each parameter is forwarded unchanged.
-            assert call_kwargs['url'] == 'https://test.example.com/mcp'
-            assert call_kwargs['headers'] == headers
-            assert call_kwargs['timeout'] == timeout_value
-            assert call_kwargs['sse_read_timeout'] == sse_value
-            assert call_kwargs['terminate_on_close'] == terminate_value
+            # Check that factory was called with headers and timeout
+            assert mock_factory.called
+            factory_kwargs = mock_factory.call_args[1]
+            assert factory_kwargs['headers'] == headers
+            # Check timeout conversion
+            if isinstance(timeout_value, timedelta):
+                expected_timeout = timeout_value.total_seconds()
+            else:
+                expected_timeout = timeout_value
+            # httpx.Timeout sets all timeout types (connect, read, write, pool) to the same value
+            assert factory_kwargs['timeout'].connect == expected_timeout
+            assert factory_kwargs['timeout'].read == expected_timeout
+            assert factory_kwargs['timeout'].write == expected_timeout
+            assert factory_kwargs['timeout'].pool == expected_timeout
+            
+            # Check streamable_http_client was called correctly
+            stream_kwargs = mock_stream_client.call_args[1]
+            assert stream_kwargs['url'] == 'https://test.example.com/mcp'
+            assert stream_kwargs['http_client'] is mock_http_client
+            assert stream_kwargs['terminate_on_close'] == terminate_value
 
 
 @pytest.mark.asyncio
@@ -170,7 +197,9 @@ async def test_custom_httpx_client_factory_is_passed(mock_session, mock_streams)
     custom_factory = Mock()
 
     with patch('boto3.Session', return_value=mock_session):
-        with patch('mcp_proxy_for_aws.client.streamablehttp_client') as mock_stream_client:
+        with patch('mcp_proxy_for_aws.client.streamable_http_client') as mock_stream_client:
+            mock_http_client = Mock()
+            custom_factory.return_value = mock_http_client
             mock_stream_client.return_value.__aenter__ = AsyncMock(
                 return_value=(mock_read, mock_write, mock_get_session)
             )
@@ -183,7 +212,10 @@ async def test_custom_httpx_client_factory_is_passed(mock_session, mock_streams)
             ):
                 pass
 
-            assert mock_stream_client.call_args[1]['httpx_client_factory'] is custom_factory
+            # Check that the custom factory was called
+            assert custom_factory.called
+            # Check that the http_client from custom factory was passed to streamable_http_client
+            assert mock_stream_client.call_args[1]['http_client'] is mock_http_client
 
 
 @pytest.mark.asyncio
@@ -198,7 +230,7 @@ async def mock_aexit(*_):
         cleanup_called = True
 
     with patch('boto3.Session', return_value=mock_session):
-        with patch('mcp_proxy_for_aws.client.streamablehttp_client') as mock_stream_client:
+        with patch('mcp_proxy_for_aws.client.streamable_http_client') as mock_stream_client:
             mock_stream_client.return_value.__aenter__ = AsyncMock(
                 return_value=(mock_read, mock_write, mock_get_session)
             )
@@ -220,7 +252,7 @@ async def test_credentials_parameter_with_region(mock_streams):
     creds = Credentials('test_key', 'test_secret', 'test_token')
 
     with patch('mcp_proxy_for_aws.client.SigV4HTTPXAuth') as mock_auth_cls:
-        with patch('mcp_proxy_for_aws.client.streamablehttp_client') as mock_stream_client:
+        with patch('mcp_proxy_for_aws.client.streamable_http_client') as mock_stream_client:
             mock_auth = Mock()
             mock_auth_cls.return_value = mock_auth
             mock_stream_client.return_value.__aenter__ = AsyncMock(
@@ -264,7 +296,7 @@ async def test_credentials_parameter_bypasses_boto3_session(mock_streams):
 
     with patch('boto3.Session') as mock_boto:
         with patch('mcp_proxy_for_aws.client.SigV4HTTPXAuth'):
-            with patch('mcp_proxy_for_aws.client.streamablehttp_client') as mock_stream_client:
+            with patch('mcp_proxy_for_aws.client.streamable_http_client') as mock_stream_client:
                 mock_stream_client.return_value.__aenter__ = AsyncMock(
                     return_value=(mock_read, mock_write, mock_get_session)
                 )