support for Dynamo Feature: ReturnValuesOnConditionCheckFailure

[vincent-ogury]

Hi,

Can you add support of ReturnValuesOnConditionCheckFailure parameters in putItem,updateItem,batchWriteItem ...

https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_ConditionCheck.html

When the API thrown an error with code = 'ConditionalCheckFailedException' Then the err include an "Item" containing the document in the db:

const cli = new AWS.DynamoDB({region:'local', endpoint: process.env.MOCK_DYNAMODB_ENDPOINT})
try {
  await cli.putItem({TableName: 'X', Item: {_id:{S:'test'}, v:{N:"1"}}}).promise()
  await cli.putItem({TableName: 'X', Item: {_id:{S:'test'}, v:{N:"3"}}
    ReturnValuesOnConditionCheckFailure: 'OLD_OLD',
    ExpressionAttributeNames: {'#V' : 'v'},
    ConditionExpression: '#V = :V',
    ExpressionAttributeValues: {':V':{N:"2}}
  }).promise()
} catch (err) {
  console.debug(err.code, err.Item)
  // Item = { _id : {S: "test"}, v: {N: "1}}
}

It works when I use the real dynamodb directly, and failed with this module or the dynamodb local provided by amazon. this feature were release in july this year.

Thanks

[kaspar-p]

As of December 14, 2023, DynamoDB Local supports this feature. Can it be supported here, too? https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DynamoDBLocalHistory.html