remove_multiple_fields

Remove multiple fields from a single record and return the removed values. Return None if the removals failed.

removed_items: Optional[dict] = table_client.remove_multiple_fields(
    key_value=str, removers={
        str: FieldRemover(field_path=str, query_kwargs=Optional[dict]),
        str: FieldRemover(field_path=str, query_kwargs=Optional[dict])
    },
    data_validation=bool = True
)

Parameters#

Property name	Required	Accepted types	Default	Description
key_value	YES	Any	-	The path expression to target the attribute to set/update in your record. See Field path selectors
removers	YES	Dict[str, FieldRemover]	-	A dictionary with the keys that will be used to return the removed items, and the values being FieldRemover's to select the field's to remove.
data_validation	NO	bool	True	Whether data validation from your table model should be applied on the retrieved data.

Availability#

Table	Available
DynamoDBBasicTable	✅
DynamoDBCachingTable	✅
ExternalDynamoDBApiBasicTable	✅
ExternalDynamoDBApiCachingTable	✅

Example#

Queried record#

{
  "userId": "x42",
  "shoppingCartItems": {
    "i42": {
      "productName": "Soluble coffee jar",
      "quantity": 8
    }
  },
  "tokens": {
    "t32": {
      "expirationTimestamp": "1618322249"
    }
  }
}

Code#

from StructNoSQL import TableDataModel, DynamoDBBasicTable, PrimaryIndex, BaseField, MapModel, FieldRemover
from typing import Optional, Dict


class UsersTableModel(TableDataModel):
    userId = BaseField(field_type=str, required=True)
    class ShoppingCartItemModel(MapModel):
        productName = BaseField(field_type=str, required=True)
        quantity = BaseField(field_type=int, required=True)
    shoppingCartItems = BaseField(field_type=Dict[str, ShoppingCartItemModel], key_name='itemId', required=False)
    class AuthTokenModel(MapModel):
        expirationTimestamp = BaseField(field_type=int, required=True)
    tokens = BaseField(field_type=Dict[str, AuthTokenModel], key_name='tokenId', required=False)


class UsersTable(DynamoDBBasicTable):
    def __init__(self):
        primary_index = PrimaryIndex(hash_key_name='userId', hash_key_variable_python_type=str)
        super().__init__(
            table_name='accounts-data', region_name='eu-west-2',
            data_model=UsersTableModel, primary_index=primary_index,
            auto_create_table=True
        )


table_client = UsersTable()

removed_items: Optional[dict] = table_client.remove_multiple_fields(
    key_value='x42', removers={
        'shoppingCartItem': FieldRemover(
            field_path='shoppingCartItems.{{itemId}}',
            query_kwargs={'itemId': 'i42'}
        ),
        'removedTokens': FieldRemover(field_path='tokens')
    }
)
print(f"Removed items : {removed_items}")

Output#

Removed item : {'shoppingCartItem': {'productName': '"Soluble coffee jar", 'quantity': 8}, 'removedTokens': {'t32': {'expirationTimestamp': "1618322249"}}