Update to version v4.0.4

CHANGELOG.md

@@ -5,6 +5,18 @@ 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).
 
+## [4.0.4] - 2026-01-13
+
+### Fixed
+
+- Bug where streaming failures would not properly fallback to non-streaming response delivery.
+
+### Security
+
+- Upgraded urllib3 to `2.6.3` to mitigate [CVE-2026-21441](https://avd.aquasec.com/nvd/cve-2026-21441/)
+- Upgraded react-router to `7.12.0` to mitigate [CVE-2025-59057](https://avd.aquasec.com/nvd/cve-2025-59057), [CVE-2025-68470](https://avd.aquasec.com/nvd/cve-2025-68470), [CVE-2026-21884](https://avd.aquasec.com/nvd/cve-2026-21884), [CVE-2026-22029](https://avd.aquasec.com/nvd/cve-2026-22029) and [CVE-2026-22030](https://avd.aquasec.com/nvd/cve-2026-22030)
+- Upgrade werkzeug to `3.1.5` to mitigate [CVE-2026-21860](https://avd.aquasec.com/nvd/cve-2026-21860)
+
 ## [4.0.3] - 2025-12-31
 
 ### Security

deployment/ecr/gaab-strands-agent/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "gaab-strands-agent"
-version = "4.0.3"
+version = "4.0.4"
 description = "GAAB Strands Agent Runtime for Amazon Bedrock AgentCore"
 readme = "README.md"
 requires-python = ">=3.13"

deployment/ecr/gaab-strands-workflow-agent/pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "gaab-strands-workflow-agent"
-version = "1.0.0"
+version = "4.0.4"
 description = "GAAB Strands Workflow Agent Runtime for Amazon Bedrock AgentCore"
 readme = "README.md"
 requires-python = ">=3.13"

source/infrastructure/cdk.json

@@ -64,7 +64,7 @@
     "@custom-bundler/unit-test": false,
     "solution_id": "SO0276",
     "solution_name": "generative-ai-application-builder-on-aws",
-    "solution_version": "v4.0.3",
+    "solution_version": "v4.0.4",
     "app_registry_name": "GAAB",
     "application_type": "AWS-Solutions",
     "application_trademark_name": "Generative AI Application Builder on AWS",

source/infrastructure/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@amzn/gen-ai-app-builder-on-aws-infrastructure",
-  "version": "4.0.3",
+  "version": "4.0.4",
   "bin": {
     "infrastructure": "bin/gen-ai-app-builder.js"
   },

source/infrastructure/test/mock-lambda-func/node-lambda/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@amzn/node-lambda",
-  "version": "4.0.3",
+  "version": "4.0.4",
   "description": "A mock lambda implementation for CDK infrastructure unit",
   "main": "index.js",
   "scripts": {

source/infrastructure/test/mock-lambda-func/python-lambda/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "mock-lambda-function"
-version = "4.0.3"
+version = "4.0.4"
 authors = [ "Amazon Web Services" ]
 description = "Mock lambda implementation to unit test infrastructure code"
 packages = [

source/infrastructure/test/mock-lambda-func/typescript-lambda/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@amzn/mock-typescript-lambda",
-  "version": "4.0.3",
+  "version": "4.0.4",
   "description": "A mock lambda implementation for CDK infrastructure unit",
   "main": "index.ts",
   "scripts": {

source/infrastructure/test/mock-ui/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@amzn/mock-react-app",
-  "version": "4.0.3",
+  "version": "4.0.4",
   "description": "Mock Reactjs app used for unit testing constructs",
   "devDependencies": {
     "@babel/plugin-proposal-private-property-in-object": "^7.21.11",

source/lambda/agentcore-invocation/pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "agent-invocation"
-version = "4.0.3"
+version = "4.0.4"
 authors = [ "Amazon Web Services" ]
 description = "Lambda implementation for agent invocation feature"
 packages = [
@@ -31,7 +31,7 @@ pytest-env = "1.1.5"
 PyYAML = "6.0.2"
 setuptools = "80.8.0"
 requests = "2.32.4"
-urllib3 = "2.6.1"
+urllib3 = "2.6.3"
 boto3-layer = { path = "../layers/aws_boto3/", develop = true }
 custom_boto3_init = { path = "../layers/custom_boto3_init", develop = true }
 

source/lambda/chat/handlers/use_case_handler.py

@@ -38,6 +38,20 @@ class UseCaseHandler:
     def __init__(self, llm_client_type: LLMChatClient.__class__):
         self.llm_client_type = llm_client_type
 
+    def check_streaming_failed(self, callbacks) -> bool:
+        """
+        Check if streaming failed by examining callbacks for has_streamed attribute.
+
+        :param callbacks: List of callback objects to check
+        :return: True if streaming was attempted but failed, False otherwise
+        """
+        streaming_failed = any(
+            hasattr(callback, "has_streamed") and not callback.has_streamed for callback in callbacks
+        )
+        if streaming_failed:
+            logger.info("Streaming was enabled but failed - using fallback")
+        return streaming_failed
+
     def handle_event(self, event: Dict[str, Any], context: LambdaContext) -> Dict:
         """
         Create a LLMChatClient concrete object type based on the configuration in `event` and
@@ -85,8 +99,13 @@ def handle_event(self, event: Dict[str, Any], context: LambdaContext) -> Dict:
                     conversation_id=conversation_id,
                     message_id=llm_client.builder.message_id,
                 )
-                if not llm_client.builder.is_streaming:
+
+                # Send response via WebSocket if streaming is disabled OR if streaming failed
+                streaming_failed = self.check_streaming_failed(llm_client.builder.callbacks)
+
+                if not llm_client.builder.is_streaming or streaming_failed:
                     socket_handler.post_response_to_connection(ai_response)
+
                 socket_handler.post_token_to_connection(END_CONVERSATION_TOKEN)
                 loop_index = loop_index + 1