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Using IAM with DynamoDB transactions

You can use Amazon Identity and Access Management (IAM) to restrict the actions that transactional operations can perform in Amazon DynamoDB. For more information about using IAM policies in DynamoDB, see Using identity-based policies (IAM policies) with Amazon DynamoDB.

Permissions for Put, Update, Delete, and Get actions are governed by the permissions used for the underlying PutItem, UpdateItem, DeleteItem, and GetItem operations. For the ConditionCheck action, you can use the dynamodb:ConditionCheck permission in IAM policies.

The following are examples of IAM policies that you can use to configure the DynamoDB transactions.

Example 1: Allow transactional operations

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "dynamodb:ConditionCheckItem",
                "dynamodb:PutItem",
                "dynamodb:UpdateItem",
                "dynamodb:DeleteItem",
                "dynamodb:GetItem"
            ],
            "Resource": [
                "arn:aws:dynamodb:*:*:table/table04"
            ]
        }
    ]
}

Example 2: Allow only transactional operations

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "dynamodb:ConditionCheckItem",
                "dynamodb:PutItem",
                "dynamodb:UpdateItem",
                "dynamodb:DeleteItem",
                "dynamodb:GetItem"
            ],
            "Resource": [
                "arn:aws:dynamodb:*:*:table/table04"
            ],
            "Condition": {
                "ForAnyValue:StringEquals": {
                    "dynamodb:EnclosingOperation": [
                        "TransactWriteItems",
                        "TransactGetItems"
                    ]
                }
            }
        }
    ]
}

Example 3: Allow nontransactional reads and writes, and block transactional reads and writes

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Deny",
            "Action": [
                "dynamodb:ConditionCheckItem",
                "dynamodb:PutItem",
                "dynamodb:UpdateItem",
                "dynamodb:DeleteItem",
                "dynamodb:GetItem"
            ],
            "Resource": [
                "arn:aws:dynamodb:*:*:table/table04"
            ],
            "Condition": {
                "ForAnyValue:StringEquals": {
                    "dynamodb:EnclosingOperation": [
                        "TransactWriteItems",
                        "TransactGetItems"
                    ]
                }
            }
        },
        {
            "Effect": "Allow",
             "Action": [
                 "dynamodb:PutItem",
                 "dynamodb:DeleteItem",
                 "dynamodb:GetItem",
                 "dynamodb:UpdateItem"
             ],
             "Resource": [
                 "arn:aws:dynamodb:*:*:table/table04"
             ]
         }
    ]
}

Example 4: Prevent information from being returned on a ConditionCheck failure

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "dynamodb:ConditionCheckItem",
                "dynamodb:PutItem",
                "dynamodb:UpdateItem",
                "dynamodb:DeleteItem",
                "dynamodb:GetItem"
            ],
            "Resource": "arn:aws:dynamodb:*:*:table/table01",
            "Condition": {
                "StringEqualsIfExists": {
                    "dynamodb:ReturnValues": "NONE"
                }
            }
        }
    ]
}