Question

在移动应用程序中，我希望lambda函数仅能够访问DynamoDB中的行，其中键是调用Lambda的userId。我已设定以下政策，但我不断获得

User: arn:aws:sts::XXX:assumed-role/FederatedIdentityRole/CognitoIdentityCredentials is not authorized to perform: dynamodb:GetItem on resource: arn:aws:dynamodb:us-east-1:XXX:table/UserData

欢迎任何提示。谢谢

以下是Lambda的政策：

{
            "Sid": "VisualEditor0",
            "Effect": "Allow",
            "Action": [
                "dynamodb:BatchGetItem",
                "dynamodb:BatchWriteItem",
                "dynamodb:PutItem",
                "dynamodb:GetItem",
                "dynamodb:Query",
                "dynamodb:UpdateItem"
            ],
            "Resource": [
                "arn:aws:dynamodb:us-east-1:XXX:table/UserData"
            ],
            "Condition": {
                "ForAllValues:StringEquals": {
                    "dynamodb:LeadingKeys": "${cognito-identity.amazonaws.com:sub}"
                }
            }
        }

Answer 1

我刚刚发现${cognito-identity.amazonaws.com:sub}并没有真正引用您从Cognito用户池中获得的身份验证令牌中的sub字段，而是引用了您从Cognito用户池中获得的IdentityId该用户的identityPool！

AWS Lambda使用呼叫者身份

1 个答案: