DynamoDB

Amazon DynamoDB parameter retrieval and caching utility

CLASS	DESCRIPTION
DynamoDBProvider	Amazon DynamoDB Parameter Provider

DynamoDBProvider

DynamoDBProvider(
    table_name: str,
    key_attr: str = "id",
    sort_attr: str = "sk",
    value_attr: str = "value",
    endpoint_url: str | None = None,
    config: Config | None = None,
    boto_config: Config | None = None,
    boto3_session: boto3.session.Session | None = None,
    boto3_client: DynamoDBServiceResource | None = None,
)

Bases: BaseProvider

Amazon DynamoDB Parameter Provider

PARAMETER	DESCRIPTION
table_name	Name of the DynamoDB table that stores parameters TYPE: str
key_attr	Hash key for the DynamoDB table (default to 'id') TYPE: str DEFAULT: 'id'
sort_attr	Name of the DynamoDB table sort key (defaults to 'sk'), used only for get_multiple TYPE: str DEFAULT: 'sk'
value_attr	Attribute that contains the values in the DynamoDB table (defaults to 'value') TYPE: str DEFAULT: 'value'
endpoint_url	Complete url to reference local DynamoDB instance, e.g. http://localhost:8080 TYPE: str | None DEFAULT: None
config	Botocore configuration to pass during client initialization TYPE: Config | None DEFAULT: None
boto3_session	Boto3 session to create a boto3_client from TYPE: Session DEFAULT: None
boto3_client	Boto3 DynamoDB Resource Client to use; boto3_session will be ignored if both are provided TYPE: DynamoDBServiceResource | None DEFAULT: None

Example

Retrieves a parameter value from a DynamoDB table

In this example, the DynamoDB table uses id as hash key and stores the value in the value attribute. The parameter item looks like this:

{ "id": "my-parameters", "value": "Parameter value a" }

>>> from aws_lambda_powertools.utilities.parameters import DynamoDBProvider
>>> ddb_provider = DynamoDBProvider("ParametersTable")
>>>
>>> value = ddb_provider.get("my-parameter")
>>>
>>> print(value)
My parameter value

Retrieves a parameter value from a DynamoDB table that has custom attribute names

>>> from aws_lambda_powertools.utilities.parameters import DynamoDBProvider
>>> ddb_provider = DynamoDBProvider(
...     "ParametersTable",
...     key_attr="my-id",
...     value_attr="my-value"
... )
>>>
>>> value = ddb_provider.get("my-parameter")
>>>
>>> print(value)
My parameter value

Retrieves a parameter value from a DynamoDB table in another AWS region

>>> from botocore.config import Config
>>> from aws_lambda_powertools.utilities.parameters import DynamoDBProvider
>>>
>>> config = Config(region_name="us-west-1")
>>> ddb_provider = DynamoDBProvider("ParametersTable", config=config)
>>>
>>> value = ddb_provider.get("my-parameter")
>>>
>>> print(value)
My parameter value

Retrieves a parameter value from a DynamoDB table passing options to the SDK call

>>> from aws_lambda_powertools.utilities.parameters import DynamoDBProvider
>>> ddb_provider = DynamoDBProvider("ParametersTable")
>>>
>>> value = ddb_provider.get("my-parameter", ConsistentRead=True)
>>>
>>> print(value)
My parameter value

Retrieves multiple values from a DynamoDB table

In this case, the provider will use a sort key to retrieve multiple values using a query under the hood. This expects that the sort key is named sk. The DynamoDB table contains three items looking like this:

{ "id": "my-parameters", "sk": "a", "value": "Parameter value a" }
{ "id": "my-parameters", "sk": "b", "value": "Parameter value b" }
{ "id": "my-parameters", "sk": "c", "value": "Parameter value c" }

>>> from aws_lambda_powertools.utilities.parameters import DynamoDBProvider
>>> ddb_provider = DynamoDBProvider("ParametersTable")
>>>
>>> values = ddb_provider.get_multiple("my-parameters")
>>>
>>> for key, value in values.items():
...     print(key, value)
a   Parameter value a
b   Parameter value b
c   Parameter value c

Retrieves multiple values from a DynamoDB table that has custom attribute names

In this case, the provider will use a sort key to retrieve multiple values using a query under the hood.

>>> from aws_lambda_powertools.utilities.parameters import DynamoDBProvider
>>> ddb_provider = DynamoDBProvider(
...     "ParametersTable",
...     key_attr="my-id",
...     sort_attr="my-sort-key",
...     value_attr="my-value"
... )
>>>
>>> values = ddb_provider.get_multiple("my-parameters")
>>>
>>> for key, value in values.items():
...     print(key, value)
a   Parameter value a
b   Parameter value b
c   Parameter value c

Retrieves multiple values from a DynamoDB table passing options to the SDK calls

>>> from aws_lambda_powertools.utilities.parameters import DynamoDBProvider
>>> ddb_provider = DynamoDBProvider("ParametersTable")
>>>
>>> values = ddb_provider.get_multiple("my-parameters", ConsistentRead=True)
>>>
>>> for key, value in values.items():
...     print(key, value)
a   Parameter value a
b   Parameter value b
c   Parameter value c

Source code in aws_lambda_powertools/utilities/parameters/dynamodb.py

def __init__(
    self,
    table_name: str,
    key_attr: str = "id",
    sort_attr: str = "sk",
    value_attr: str = "value",
    endpoint_url: str | None = None,
    config: Config | None = None,
    boto_config: Config | None = None,
    boto3_session: boto3.session.Session | None = None,
    boto3_client: DynamoDBServiceResource | None = None,
):
    """
    Initialize the DynamoDB client
    """
    if config:
        warnings.warn(
            message="The 'config' parameter is deprecated in V3 and will be removed in V4. "
            "Please use 'boto_config' instead.",
            category=PowertoolsDeprecationWarning,
            stacklevel=2,
        )

    if boto3_client is None:
        boto3_session = boto3_session or boto3.session.Session()
        boto3_client = boto3_session.resource("dynamodb", config=boto_config or config, endpoint_url=endpoint_url)

    self.table = boto3_client.Table(table_name)
    self.key_attr = key_attr
    self.sort_attr = sort_attr
    self.value_attr = value_attr

    super().__init__(resource=boto3_client)