Module aws_lambda_powertools.utilities.data_classes.alb_event

Classes

class ALBEvent (data: Dict[str, Any], json_deserializer: Optional[Callable] = None)

Application load balancer event

Documentation:

Parameters

data : Dict[str, Any]
Lambda Event Source Event payload
json_deserializer : Callable, optional
function to deserialize str, bytes, bytearray containing a JSON document to a Python obj, by default json.loads
Expand source code 
class ALBEvent(BaseProxyEvent):
    """Application load balancer event

    Documentation:
    --------------
    - https://docs.aws.amazon.com/lambda/latest/dg/services-alb.html
    - https://docs.aws.amazon.com/elasticloadbalancing/latest/application/lambda-functions.html
    """

    @property
    def request_context(self) -> ALBEventRequestContext:
        return ALBEventRequestContext(self._data)

    @property
    def multi_value_query_string_parameters(self) -> Dict[str, List[str]]:
        return self.get("multiValueQueryStringParameters") or {}

    @property
    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 super().resolved_query_string_parameters

    @property
    def resolved_headers_field(self) -> Dict[str, Any]:
        headers: Dict[str, Any] = {}

        if self.multi_value_headers:
            headers = self.multi_value_headers
        else:
            headers = self.headers

        return {key.lower(): value for key, value in headers.items()}

    @property
    def multi_value_headers(self) -> Optional[Dict[str, List[str]]]:
        return self.get("multiValueHeaders")

    def header_serializer(self) -> BaseHeadersSerializer:
        # When using the ALB integration, the `multiValueHeaders` feature can be disabled (default) or enabled.
        # We can determine if the feature is enabled by looking if the event has a `multiValueHeaders` key.
        if self.multi_value_headers:
            return MultiValueHeadersSerializer()

        return SingleValueHeadersSerializer()

Ancestors

  • BaseProxyEvent
  • DictWrapper
  • collections.abc.Mapping
  • collections.abc.Collection
  • collections.abc.Sized
  • collections.abc.Iterable
  • collections.abc.Container

Instance variables

prop multi_value_headers : Optional[Dict[str, List[str]]]
Expand source code 
@property
def multi_value_headers(self) -> Optional[Dict[str, List[str]]]:
    return self.get("multiValueHeaders")
prop multi_value_query_string_parameters : Dict[str, List[str]]
Expand source code 
@property
def multi_value_query_string_parameters(self) -> Dict[str, List[str]]:
    return self.get("multiValueQueryStringParameters") or {}
prop request_context : ALBEventRequestContext
Expand source code 
@property
def request_context(self) -> ALBEventRequestContext:
    return ALBEventRequestContext(self._data)

Methods

def header_serializer(self) ‑> BaseHeadersSerializer

Inherited members

class ALBEventRequestContext (data: Dict[str, Any], json_deserializer: Optional[Callable] = None)

Provides a single read only access to a wrapper dict

Parameters

data : Dict[str, Any]
Lambda Event Source Event payload
json_deserializer : Callable, optional
function to deserialize str, bytes, bytearray containing a JSON document to a Python obj, by default json.loads
Expand source code 
class ALBEventRequestContext(DictWrapper):
    @property
    def elb_target_group_arn(self) -> str:
        """Target group arn for your Lambda function"""
        return self["requestContext"]["elb"]["targetGroupArn"]

Ancestors

  • DictWrapper
  • collections.abc.Mapping
  • collections.abc.Collection
  • collections.abc.Sized
  • collections.abc.Iterable
  • collections.abc.Container

Instance variables

prop elb_target_group_arn : str

Target group arn for your Lambda function

Expand source code 
@property
def elb_target_group_arn(self) -> str:
    """Target group arn for your Lambda function"""
    return self["requestContext"]["elb"]["targetGroupArn"]

Inherited members