Module aws_lambda_powertools.utilities.parser.envelopes.dynamodb
Expand source code
import logging
from typing import Any, Dict, List, Optional, Type, Union
from ..models import DynamoDBStreamModel
from ..types import Model
from .base import BaseEnvelope
logger = logging.getLogger(__name__)
class DynamoDBStreamEnvelope(BaseEnvelope):
"""DynamoDB Stream Envelope to extract data within NewImage/OldImage
Note: Values are the parsed models. Images' values can also be None, and
length of the list is the record's amount in the original event.
"""
def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model]) -> List[Dict[str, Optional[Model]]]:
"""Parses DynamoDB Stream records found in either NewImage and OldImage with model provided
Parameters
----------
data : Dict
Lambda event to be parsed
model : Type[Model]
Data model provided to parse after extracting data using envelope
Returns
-------
List
List of dictionaries with NewImage and OldImage records parsed with model provided
"""
logger.debug(f"Parsing incoming data with DynamoDB Stream model {DynamoDBStreamModel}")
parsed_envelope = DynamoDBStreamModel.parse_obj(data)
logger.debug(f"Parsing DynamoDB Stream new and old records with {model}")
return [
{
"NewImage": self._parse(data=record.dynamodb.NewImage, model=model),
"OldImage": self._parse(data=record.dynamodb.OldImage, model=model),
}
for record in parsed_envelope.Records
]
Classes
class DynamoDBStreamEnvelope
-
DynamoDB Stream Envelope to extract data within NewImage/OldImage
Note: Values are the parsed models. Images' values can also be None, and length of the list is the record's amount in the original event.
Expand source code
class DynamoDBStreamEnvelope(BaseEnvelope): """DynamoDB Stream Envelope to extract data within NewImage/OldImage Note: Values are the parsed models. Images' values can also be None, and length of the list is the record's amount in the original event. """ def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model]) -> List[Dict[str, Optional[Model]]]: """Parses DynamoDB Stream records found in either NewImage and OldImage with model provided Parameters ---------- data : Dict Lambda event to be parsed model : Type[Model] Data model provided to parse after extracting data using envelope Returns ------- List List of dictionaries with NewImage and OldImage records parsed with model provided """ logger.debug(f"Parsing incoming data with DynamoDB Stream model {DynamoDBStreamModel}") parsed_envelope = DynamoDBStreamModel.parse_obj(data) logger.debug(f"Parsing DynamoDB Stream new and old records with {model}") return [ { "NewImage": self._parse(data=record.dynamodb.NewImage, model=model), "OldImage": self._parse(data=record.dynamodb.OldImage, model=model), } for record in parsed_envelope.Records ]
Ancestors
- BaseEnvelope
- abc.ABC
Methods
def parse(self, data: Union[Dict[str, Any], Any, NoneType], model: Type[~Model]) ‑> List[Dict[str, Union[~Model, NoneType]]]
-
Parses DynamoDB Stream records found in either NewImage and OldImage with model provided
Parameters
data
:Dict
- Lambda event to be parsed
model
:Type[Model]
- Data model provided to parse after extracting data using envelope
Returns
List
- List of dictionaries with NewImage and OldImage records parsed with model provided
Expand source code
def parse(self, data: Optional[Union[Dict[str, Any], Any]], model: Type[Model]) -> List[Dict[str, Optional[Model]]]: """Parses DynamoDB Stream records found in either NewImage and OldImage with model provided Parameters ---------- data : Dict Lambda event to be parsed model : Type[Model] Data model provided to parse after extracting data using envelope Returns ------- List List of dictionaries with NewImage and OldImage records parsed with model provided """ logger.debug(f"Parsing incoming data with DynamoDB Stream model {DynamoDBStreamModel}") parsed_envelope = DynamoDBStreamModel.parse_obj(data) logger.debug(f"Parsing DynamoDB Stream new and old records with {model}") return [ { "NewImage": self._parse(data=record.dynamodb.NewImage, model=model), "OldImage": self._parse(data=record.dynamodb.OldImage, model=model), } for record in parsed_envelope.Records ]