fix(event-handler): multi-value query string and validation of scalar parameters (aws-powertools#3795)

Author: rubenfonseca

aws_lambda_powertools/event_handler/middlewares/openapi_validation.py

@@ -368,7 +368,10 @@ def _get_embed_body(
  return received_body, field_alias_omitted
 
 
-def _normalize_multi_query_string_with_param(query_string: Optional[Dict[str, str]], params: Sequence[ModelField]):
+def _normalize_multi_query_string_with_param(
+ query_string: Dict[str, List[str]],
+ params: Sequence[ModelField],
+) -> Dict[str, Any]:
  """
  Extract and normalize resolved_query_string_parameters
 
@@ -383,15 +386,15 @@ def _normalize_multi_query_string_with_param(query_string: Optional[Dict[str, st
  -------
  A dictionary containing the processed multi_query_string_parameters.
  """
- if query_string:
-  for param in filter(is_scalar_field, params):
-  try:
-  # if the target parameter is a scalar, we keep the first value of the query string
-  # regardless if there are more in the payload
-  query_string[param.alias] = query_string[param.alias][0]
-  except KeyError:
-  pass
- return query_string
+ resolved_query_string: Dict[str, Any] = query_string
+ for param in filter(is_scalar_field, params):
+ try:
+ # if the target parameter is a scalar, we keep the first value of the query string
+ # regardless if there are more in the payload
+ resolved_query_string[param.alias] = query_string[param.alias][0]
+ except KeyError:
+ pass
+ return resolved_query_string
 
 
 def _normalize_multi_header_values_with_param(headers: Optional[Dict[str, str]], params: Sequence[ModelField]):

aws_lambda_powertools/utilities/data_classes/alb_event.py

@@ -36,11 +36,11 @@ def multi_value_query_string_parameters(self) -> Optional[Dict[str, List[str]]]:
  return self.get("multiValueQueryStringParameters")
 
  @property
- def resolved_query_string_parameters(self) -> Optional[Dict[str, Any]]:
+ def resolved_query_string_parameters(self) -> Dict[str, List[str]]:
  if self.multi_value_query_string_parameters:
  return self.multi_value_query_string_parameters
 
- return self.query_string_parameters
+ return super().resolved_query_string_parameters
 
  @property
  def resolved_headers_field(self) -> Optional[Dict[str, Any]]:

aws_lambda_powertools/utilities/data_classes/api_gateway_proxy_event.py

@@ -119,11 +119,11 @@ def multi_value_query_string_parameters(self) -> Optional[Dict[str, List[str]]]:
  return self.get("multiValueQueryStringParameters")
 
  @property
- def resolved_query_string_parameters(self) -> Optional[Dict[str, Any]]:
+ def resolved_query_string_parameters(self) -> Dict[str, List[str]]:
  if self.multi_value_query_string_parameters:
  return self.multi_value_query_string_parameters
 
- return self.query_string_parameters
+ return super().resolved_query_string_parameters
 
  @property
  def resolved_headers_field(self) -> Optional[Dict[str, Any]]:
@@ -318,16 +318,6 @@ def http_method(self) -> str:
  def header_serializer(self):
  return HttpApiHeadersSerializer()
 
- @property
- def resolved_query_string_parameters(self) -> Optional[Dict[str, Any]]:
- if self.query_string_parameters is not None:
- query_string = {
- key: value.split(",") if "," in value else value for key, value in self.query_string_parameters.items()
- }
- return query_string
-
- return {}
-
  @property
  def resolved_headers_field(self) -> Optional[Dict[str, Any]]:
  if self.headers is not None:

aws_lambda_powertools/utilities/data_classes/bedrock_agent_event.py

@@ -109,10 +109,6 @@ def query_string_parameters(self) -> Optional[Dict[str, str]]:
  # together with the other parameters. So we just return all parameters here.
  return {x["name"]: x["value"] for x in self["parameters"]} if self.get("parameters") else None
 
- @property
- def resolved_query_string_parameters(self) -> Optional[Dict[str, str]]:
- return self.query_string_parameters
-
  @property
  def resolved_headers_field(self) -> Optional[Dict[str, Any]]:
  return {}

aws_lambda_powertools/utilities/data_classes/common.py

@@ -104,15 +104,19 @@ def query_string_parameters(self) -> Optional[Dict[str, str]]:
  return self.get("queryStringParameters")
 
  @property
- def resolved_query_string_parameters(self) -> Optional[Dict[str, str]]:
+ def resolved_query_string_parameters(self) -> Dict[str, List[str]]:
  """
  This property determines the appropriate query string parameter to be used
  as a trusted source for validating OpenAPI.
 
  This is necessary because different resolvers use different formats to encode
  multi query string parameters.
  """
- return self.query_string_parameters
+ if self.query_string_parameters is not None:
+ query_string = {key: value.split(",") for key, value in self.query_string_parameters.items()}
+ return query_string
+
+ return {}
 
  @property
  def resolved_headers_field(self) -> Optional[Dict[str, Any]]:
@@ -186,17 +190,15 @@ def get_header_value(
  name: str,
  default_value: str,
  case_sensitive: Optional[bool] = False,
- ) -> str:
- ...
+ ) -> str: ...
 
  @overload
  def get_header_value(
  self,
  name: str,
  default_value: Optional[str] = None,
  case_sensitive: Optional[bool] = False,
- ) -> Optional[str]:
- ...
+ ) -> Optional[str]: ...
 
  def get_header_value(
  self,

aws_lambda_powertools/utilities/data_classes/vpc_lattice.py

@@ -73,17 +73,15 @@ def get_header_value(
  name: str,
  default_value: str,
  case_sensitive: Optional[bool] = False,
- ) -> str:
- ...
+ ) -> str: ...
 
  @overload
  def get_header_value(
  self,
  name: str,
  default_value: Optional[str] = None,
  case_sensitive: Optional[bool] = False,
- ) -> Optional[str]:
- ...
+ ) -> Optional[str]: ...
 
  def get_header_value(
  self,
@@ -140,10 +138,6 @@ def query_string_parameters(self) -> Dict[str, str]:
  """The request query string parameters."""
  return self["query_string_parameters"]
 
- @property
- def resolved_query_string_parameters(self) -> Optional[Dict[str, str]]:
- return self.query_string_parameters
-
  @property
  def resolved_headers_field(self) -> Optional[Dict[str, Any]]:
  if self.headers is not None:
@@ -255,17 +249,21 @@ def path(self) -> str:
 
  @property
  def request_context(self) -> vpcLatticeEventV2RequestContext:
- """he VPC Lattice v2 Event request context."""
+ """The VPC Lattice v2 Event request context."""
  return vpcLatticeEventV2RequestContext(self["requestContext"])
 
  @property
  def query_string_parameters(self) -> Optional[Dict[str, str]]:
- """The request query string parameters."""
- return self.get("queryStringParameters")
+ """The request query string parameters.
 
- @property
- def resolved_query_string_parameters(self) -> Optional[Dict[str, str]]:
- return self.query_string_parameters
+ For VPC Lattice V2, the queryStringParameters will contain a Dict[str, List[str]]
+ so to keep compatibility with existing utilities, we merge all the values with a comma.
+ """
+ params = self.get("queryStringParameters")
+ if params:
+ return {key: ",".join(value) for key, value in params.items()}
+ else:
+ return None
 
  @property
  def resolved_headers_field(self) -> Optional[Dict[str, str]]:

tests/functional/event_handler/conftest.py

@@ -2,6 +2,8 @@
 
 import pytest
 
+from tests.functional.utils import load_event
+
 
 @pytest.fixture
 def json_dump():
@@ -39,3 +41,33 @@ def validation_schema():
 @pytest.fixture
 def raw_event():
  return {"message": "hello hello", "username": "blah blah"}
+
+
+@pytest.fixture
+def gw_event():
+ return load_event("apiGatewayProxyEvent.json")
+
+
+@pytest.fixture
+def gw_event_http():
+ return load_event("apiGatewayProxyV2Event.json")
+
+
+@pytest.fixture
+def gw_event_alb():
+ return load_event("albMultiValueQueryStringEvent.json")
+
+
+@pytest.fixture
+def gw_event_lambda_url():
+ return load_event("lambdaFunctionUrlEventWithHeaders.json")
+
+
+@pytest.fixture
+def gw_event_vpc_lattice():
+ return load_event("vpcLatticeV2EventWithHeaders.json")
+
+
+@pytest.fixture
+def gw_event_vpc_lattice_v1():
+ return load_event("vpcLatticeEvent.json")