chore(event_handlers): apply suggestions from code review

Co-authored-by: Heitor Lessa <[email protected]>

Author: rubenfonseca

aws_lambda_powertools/event_handler/lambda_function_url.py

@@ -10,15 +10,15 @@ class LambdaFunctionUrlResolver(ApiGatewayResolver):
 
     Notes:
     -----
-    For now, this seems to work the same way as API Gateway HTTP APIs Payload Format Version 2.0.
+    Lambda Function URL follows the API Gateway HTTP APIs Payload Format Version 2.0.
 
     Documentation:
     - https://docs.aws.amazon.com/lambda/latest/dg/urls-configuration.html
     - https://docs.aws.amazon.com/lambda/latest/dg/urls-invocation.html#urls-payloads
 
     Examples
     --------
-    Simple example with a custom lambda handler using the Tracer capture_lambda_handler decorator
+    Simple example integrating with Tracer
 
     ```python
     from aws_lambda_powertools import Tracer
@@ -34,7 +34,7 @@ def simple_get():
     @app.post("/post-call")
     def simple_post():
         post_data: dict = app.current_event.json_body
-        return {"message": post_data["value"]}
+        return {"message": post_data}
 
     @tracer.capture_lambda_handler
     def lambda_handler(event, context):

aws_lambda_powertools/logging/correlation_paths.py

@@ -6,5 +6,5 @@
 APPSYNC_RESOLVER = 'request.headers."x-amzn-trace-id"'
 APPLICATION_LOAD_BALANCER = 'headers."x-amzn-trace-id"'
 EVENT_BRIDGE = "id"
-LAMBDA_FUNCTION_URL = "requestContext.requestId"
+LAMBDA_FUNCTION_URL = API_GATEWAY_REST
 S3_OBJECT_LAMBDA = "xAmzRequestId"

aws_lambda_powertools/utilities/data_classes/api_gateway_proxy_event.py

@@ -127,21 +127,21 @@ def caller_id(self) -> Optional[str]:
     def cognito_amr(self) -> Optional[List[str]]:
         """This represents how the user was authenticated.
         AMR stands for  Authentication Methods References as per the openid spec"""
-        cognito_identity = self["cognitoIdentity"] or {}
+        cognito_identity = self["cognitoIdentity"] or {}  # not available in FunctionURL
         return cognito_identity.get("amr")
 
     @property
     def cognito_identity_id(self) -> Optional[str]:
         """The Amazon Cognito identity ID of the caller making the request.
         Available only if the request was signed with Amazon Cognito credentials."""
-        cognito_identity = self.get("cognitoIdentity") or {}
+        cognito_identity = self.get("cognitoIdentity") or {}  # not available in FunctionURL
         return cognito_identity.get("identityId")
 
     @property
     def cognito_identity_pool_id(self) -> Optional[str]:
         """The Amazon Cognito identity pool ID of the caller making the request.
         Available only if the request was signed with Amazon Cognito credentials."""
-        cognito_identity = self.get("cognitoIdentity") or {}
+        cognito_identity = self.get("cognitoIdentity") or {}  # not available in FunctionURL
         return cognito_identity.get("identityPoolId")
 
     @property
@@ -163,12 +163,12 @@ def user_id(self) -> Optional[str]:
 class RequestContextV2Authorizer(DictWrapper):
     @property
     def jwt_claim(self) -> Optional[Dict[str, Any]]:
-        jwt = self.get("jwt") or {}
+        jwt = self.get("jwt") or {}  # not available in FunctionURL
         return jwt.get("claims")
 
     @property
     def jwt_scopes(self) -> Optional[List[str]]:
-        jwt = self.get("jwt") or {}
+        jwt = self.get("jwt") or {}  # not available in FunctionURL
         return jwt.get("scopes")
 
     @property

aws_lambda_powertools/utilities/data_classes/common.py

@@ -395,6 +395,7 @@ def time_epoch(self) -> int:
     @property
     def authentication(self) -> Optional[RequestContextClientCert]:
         """Optional when using mutual TLS authentication"""
+        # FunctionURL might have NONE as AuthZ
         authentication = self["requestContext"].get("authentication") or {}
         client_cert = authentication.get("clientCert")
         return None if client_cert is None else RequestContextClientCert(client_cert)

aws_lambda_powertools/utilities/data_classes/lambda_function_url_event.py

@@ -6,9 +6,9 @@ class LambdaFunctionUrlEvent(APIGatewayProxyEventV2):
 
     Notes:
     -----
-    For now, this seems to follow the exact same payload as HTTP APIs Payload Format Version 2.0.
-    Certain keys in this payload format don't make sense for function urls (e.g: `routeKey`, `stage`).
-    These keys will have default values that come on the payload, but they are not useful since they can't be changed.
+    Lambda Function URL follows the API Gateway HTTP APIs Payload Format Version 2.0.
+    
+    Keys related to API Gateway features not available in Function URL use a sentinel value (e.g.`routeKey`, `stage`).
 
     Documentation:
     - https://docs.aws.amazon.com/lambda/latest/dg/urls-configuration.html

docs/core/event_handler/api_gateway.md

@@ -97,7 +97,7 @@ When using Amazon Application Load Balancer (ALB) to front your Lambda functions
 
 #### Lambda Function URL
 
-When using an [AWS Lambda Function URL](https://docs.aws.amazon.com/lambda/latest/dg/urls-configuration.html), you can use `LambdaFunctionUrlResolver`.
+When using [AWS Lambda Function URL](https://docs.aws.amazon.com/lambda/latest/dg/urls-configuration.html), you can use `LambdaFunctionUrlResolver`.
 
 === "getting_started_lambda_function_url_resolver.py"
 
@@ -294,7 +294,7 @@ This will ensure that CORS headers are always returned as part of the response w
 
 #### Pre-flight
 
-Pre-flight (OPTIONS) calls are typically handled at the API Gateway or Lambda Function URL level as per [our sample infrastructure](#required-resources), no Lambda integration necessary. However, ALB expects you to handle pre-flight requests.
+Pre-flight (OPTIONS) calls are typically handled at the API Gateway or Lambda Function URL level as per [our sample infrastructure](#required-resources), no Lambda integration is necessary. However, ALB expects you to handle pre-flight requests.
 
 For convenience, we automatically handle that for you as long as you [setup CORS in the constructor level](#cors).
 
@@ -362,8 +362,9 @@ Like `compress` feature, the client must send the `Accept` header with the corre
 
 ???+ warning
     This feature requires API Gateway to configure binary media types, see [our sample infrastructure](#required-resources) for reference.
-    For Lambda Function URLs, no additional configuration is necessary.
 
+???+ note
+    Lambda Function URLs handle binary media types automatically.
 === "binary_responses.py"
 
     ```python hl_lines="14 20"
@@ -405,7 +406,7 @@ This will enable full tracebacks errors in the response, print request and respo
 
 ### Custom serializer
 
-You can instruct an event handler to use a custom serializer to best suit your needs, for example take into account Enums when serializing.
+You can instruct event handler to use a custom serializer to best suit your needs, for example take into account Enums when serializing.
 
 ```python hl_lines="35 40" title="Using a custom JSON serializer for responses"
 --8<-- "examples/event_handler_rest/src/custom_serializer.py"

docs/index.md

@@ -417,7 +417,7 @@ Core utilities such as Tracing, Logging, Metrics, and Event Handler will be avai
 | [Logger](./core/logger.md)                                                                                                                               | Structured logging made easier, and decorator to enrich structured logging with key Lambda context details                                                |
 | [Metrics](./core/metrics.md)                                                                                                                             | Custom Metrics created asynchronously via CloudWatch Embedded Metric Format (EMF)                                                                         |
 | [Event handler: AppSync](./core/event_handler/appsync.md)                                                                                                | AppSync event handler for Lambda Direct Resolver and Amplify GraphQL Transformer function                                                                 |
-| [Event handler: API Gateway, ALB and Lambda Function URL](https://awslabs.github.io/aws-lambda-powertools-python/latest/core/event_handler/api_gateway/) | Amazon API Gateway REST/HTTP API and ALB event handler for Lambda functions invoked using Proxy integration                                               |
+| [Event handler: API Gateway, ALB and Lambda Function URL](https://awslabs.github.io/aws-lambda-powertools-python/latest/core/event_handler/api_gateway/) | Amazon API Gateway REST/HTTP API and ALB event handler for Lambda functions invoked using Proxy integration, and Lambda Function URL                                               |
 | [Middleware factory](./utilities/middleware_factory.md)                                                                                                  | Decorator factory to create your own middleware to run logic before, and after each Lambda invocation                                                     |
 | [Parameters](./utilities/parameters.md)                                                                                                                  | Retrieve parameter values from AWS Systems Manager Parameter Store, AWS Secrets Manager, or Amazon DynamoDB, and cache them for a specific amount of time |
 | [Batch processing](./utilities/batch.md)                                                                                                                 | Handle partial failures for AWS SQS batch processing                                                                                                      |

examples/event_handler_lambda_function_url/sam/template.yaml

@@ -28,4 +28,4 @@ Resources:
       CodeUri: ../src
       Description: API handler function
       FunctionUrlConfig:
-        AuthType: NONE
+        AuthType: NONE  # AWS_IAM for added security beyond sample documentation