DynamoDBBackend

AWS DynamoDB result backend.

Attributes

Attribute	Type	Description
table_name	string = celery	default DynamoDB table name (default)
read_capacity_units	int = 1	Read Provisioned Throughput (default)
write_capacity_units	int = 1	Write Provisioned Throughput (default)
aws_region	string = null	AWS region (default)
endpoint_url	string = null	The endpoint URL that is passed to boto3 (local DynamoDB) (default)
time_to_live_seconds	int = null	Item time-to-live in seconds (default)
supports_autoexpire	boolean = true	Indicates that DynamoDB supports Time to Live as an auto-expiry mechanism.
implements_incr	boolean = true	Indicates that the backend supports atomic increment operations for chord functionality.

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Constructor

Signature

def DynamoDBBackend(
    url: str = null,
    table_name: str = null,
    *args: any = null,
    **kwargs: any = null
) - > null

Parameters

Name	Type	Description
url	str = null	The connection URL containing configuration details like region, credentials, and table name.
table_name	str = null	The name of the DynamoDB table to use for storing results.
*args	any = null	Variable length argument list passed to the parent class.
**kwargs	any = null	Arbitrary keyword arguments passed to the parent class.

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Methods

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client()

@classmethod
def client() - > botocore.client.DynamoDB

Provides access to the underlying Boto3 DynamoDB client, initializing it if necessary.

Returns

Type	Description
botocore.client.DynamoDB	The active DynamoDB client instance

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get()

@classmethod
def get(
    key: any
) - > bytes | null

Retrieves the value associated with a specific key from the DynamoDB table.

Parameters

Name	Type	Description
key	any	The key used to look up the stored result

Returns

Type	Description
`bytes	null`

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set()

@classmethod
def set(
    key: any,
    value: bytes
) - > null

Stores a value in the DynamoDB table for a given key, including a timestamp and optional TTL.

Parameters

Name	Type	Description
key	any	The key under which the value will be stored
value	bytes	The binary data to store

Returns

Type	Description
null	null

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mget()

@classmethod
def mget(
    keys: list
) - > list

Retrieves multiple values from the backend for a list of provided keys.

Parameters

Name	Type	Description
keys	list	A collection of keys to retrieve

Returns

Type	Description
list	A list of binary values corresponding to the input keys

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delete()

@classmethod
def delete(
    key: any
) - > null

Removes the item associated with the specified key from the DynamoDB table.

Parameters

Name	Type	Description
key	any	The key of the item to be deleted

Returns

Type	Description
null	null

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incr()

@classmethod
def incr(
    key: bytes
) - > int

Atomically increase the chord_count and return the new count

Parameters

Name	Type	Description
key	bytes	The key identifying the counter to increment

Returns

Type	Description
int	The new integer value of the counter after incrementing

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