AWS powertools documentation change

Service: powertools · 2026-03-13 · Documentation low

File: powertools/python/latest/core/event_handler/api_gateway.md

Summary

Added documentation for HttpResolverLocal development resolver with explicit warnings about production use, examples, and Swagger UI integration

Security assessment

The change adds documentation for a development-only resolver with clear warnings against production use. While this highlights security implications of misuse, there's no evidence of addressing a specific existing security vulnerability.

Diff

diff --git a/powertools/python/latest/core/event_handler/api_gateway.md b/powertools/python/latest/core/event_handler/api_gateway.md
index a34bdca67..7f6bc8e7e 100644
--- a//powertools/python/latest/core/event_handler/api_gateway.md
+++ b//powertools/python/latest/core/event_handler/api_gateway.md
@@ -55,0 +56 @@ Metrics
+              * Http Resolver (Local Development) 
@@ -229,0 +231 @@ Table of contents
+      * Http Resolver (Local Development) 
@@ -566,0 +569 @@ Resolver | AWS service
+**`HttpResolverLocal`** | Local development with ASGI servers  
@@ -1508,0 +1512,202 @@ Example payload delivered to the handler
+#### Http Resolver (Local Development)¶
+
+Local Development Only
+
+`HttpResolverLocal` is intended for local development and testing only. The API may change in future releases. **Do not use in production environments.**
+
+When developing locally, you can use `HttpResolverLocal` to run your API with any ASGI server like [uvicorn](https://www.uvicorn.org/). It implements the [ASGI specification](https://asgi.readthedocs.io/), is lightweight with no external dependencies, and the same code works on any compute platform, including Lambda.
+
+If your Lambda is behind [Lambda Web Adapter](https://github.com/awslabs/aws-lambda-web-adapter) or any other HTTP proxy that speaks the HTTP protocol, it works seamlessly.
+
+All existing resolver features work out of the box: routing, middleware, validation, OpenAPI/Swagger, CORS, exception handling, and more.
+
+**Install uvicorn** :
+    
+    
+    1
+
+| 
+    
+    
+    pip install uvicorn
+      
+  
+---|---  
+  
+Basic UsageWith Validation & SwaggerException Handling
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+| 
+    
+    
+    from aws_lambda_powertools.event_handler import HttpResolverLocal
+    
+    app = HttpResolverLocal()
+    
+    
+    @app.get("/hello/<name>")
+    def hello(name: str):
+        return {"message": f"Hello, {name}!"}
+    
+    
+    # Lambda handler - same code works in Lambda
+    handler = app
+      
+  
+---|---  
+  
+Run locally: `uvicorn app:app --reload`
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+| 
+    
+    
+    from pydantic import BaseModel
+    
+    from aws_lambda_powertools.event_handler import HttpResolverLocal
+    
+    
+    class User(BaseModel):
+        name: str
+        age: int
+    
+    
+    app = HttpResolverLocal(enable_validation=True)
+    
+    app.enable_swagger(
+        title="My API",
+        version="1.0.0",
+    )
+    
+    
+    @app.post("/users")
+    def create_user(user: User) -> dict:
+        return {"id": "123", "user": user.model_dump()}
+    
+    
+    handler = app
+      
+  
+---|---  
+  
+Access Swagger UI at `http://localhost:8000/swagger`
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+| 
+    
+    
+    from aws_lambda_powertools.event_handler import HttpResolverLocal, Response
+    
+    app = HttpResolverLocal()
+    
+    
+    class NotFoundError(Exception):
+        def __init__(self, resource: str):
+            self.resource = resource
+    
+    
+    @app.exception_handler(NotFoundError)
+    def handle_not_found_error(exc: NotFoundError):
+        return Response(
+            status_code=404,
+            content_type="application/json",
+            body={"error": "Not Found", "resource": exc.resource},
+        )
+    
+    
+    @app.not_found
+    def handle_not_found(exc: Exception):
+        return Response(
+            status_code=404,
+            content_type="application/json",
+            body={"error": "Route not found", "path": app.current_event.path},
+        )
+