Cognito和DynamoDB:"未授权执行:dynamodb:资源上的UpdateItem"

Question

在完全遵循Android上的Amazon DynamoDB"入门"指南后,我最终得到了所有正确创建的表,角色策略等以及该代码:

CognitoCachingCredentialsProvider credentialsProvider = new CognitoCachingCredentialsProvider(
        getApplicationContext(),
        "eu-west-1:01234567-abcd-8901-efab-234567890123", // Identity Pool ID
        Regions.EU_WEST_1 // Region
);

AmazonDynamoDBClient ddbClient = new AmazonDynamoDBClient(credentialsProvider);
final DynamoDBMapper mapper = new DynamoDBMapper(ddbClient);

final Book book = new Book("My new book"); // Simplified version of Book
new Thread(new Runnable() {
    @Override
    public void run() {
        mapper.save(book);
        Log.v("Sync", "Book saved!");
    }
}).start();

重要提示,与教程最大的(但无法察觉的)差异是我在欧洲,所以我的地区是eu-west-1(爱尔兰).

然而,如果正确地遵循了一切,我会收到以下错误:

com.amazonaws.AmazonServiceException: User: arn:aws:sts::012345678901:assumed-role/Cognito_BookUnauth_Role/CognitoIdentityCredentials is not authorized to perform: dynamodb:UpdateItem on resource: arn:aws:dynamodb:us-east-1:012345678901:table/Books (Service: AmazonDynamoDBv2; Status Code: 400; Error Code: AccessDeniedException; Request ID: 05OLSSM8F8EN15SO0JD8VELCNNVV4KQNSO5AEMVJF66Q9ASUAAJG)
    at com.amazonaws.http.AmazonHttpClient.handleErrorResponse(AmazonHttpClient.java:709)
    at com.amazonaws.http.AmazonHttpClient.executeHelper(AmazonHttpClient.java:385)
    at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:196)
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.invoke(AmazonDynamoDBClient.java:3257)
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.updateItem(AmazonDynamoDBClient.java:965)
    at com.amazonaws.mobileconnectors.dynamodbv2.dynamodbmapper.DynamoDBMapper$SaveObjectHandler.doUpdateItem(DynamoDBMapper.java:1173)
    at com.amazonaws.mobileconnectors.dynamodbv2.dynamodbmapper.DynamoDBMapper$2.executeLowLevelRequest(DynamoDBMapper.java:873)
    at com.amazonaws.mobileconnectors.dynamodbv2.dynamodbmapper.DynamoDBMapper$SaveObjectHandler.execute(DynamoDBMapper.java:1056)
    at com.amazonaws.mobileconnectors.dynamodbv2.dynamodbmapper.DynamoDBMapper.save(DynamoDBMapper.java:904)
    at com.amazonaws.mobileconnectors.dynamodbv2.dynamodbmapper.DynamoDBMapper.save(DynamoDBMapper.java:688)
    at com.davidferrand.books$4.run(MainActivity.java:136)
    at java.lang.Thread.run(Thread.java:818)

Answer 1

这个"错误"很棘手,我花了几个小时来解决它.本指南假定您在该us-east-1区域,并且这也是AmazonDynamoDBClient您创建的默认端点.

只要将数据库放在其他区域中,就必须在创建时明确指定区域AmazonDynamoDBClient.

最好的方法是:

AmazonDynamoDBClient ddbClient = Region.getRegion(Regions.EU_WEST_1) // CRUCIAL
    .createClient(
        AmazonDynamoDBClient.class,
        credentialsProvider,
        new ClientConfiguration()
    );