Querying DynamoDb with Global Secondary Index Error-CodePudding

I'm new to DynamoDb and the intricacies of querying it - I understand (hopefully correctly) that I need to either have a partition Key or Global Secondary Index (GSI) in order to query against that value in the table.

I know I can use Appsync to query on a GSI by setting up a resolver - and this works. However, I have a setup using the Java AWS CDK (I'm writing in Kotlin) where I'm using Appsync and routing my queries into lambda Resolvers (so that once this works, I can do more complicated things later).

The Crux of the issue is that when I setup a Lambda to resolve my query, I end up with this Error msg: com.amazonaws.services.dynamodbv2.model.AmazonDynamoDBException: Query condition missed key schema element: testName returned from the Lambda.

I think these should be the key snippets..

My DynamoDbBean..

@DynamoDbBean
data class Test(
    @get:DynamoDbPartitionKey var id: String = "",
    @get:DynamoDbSecondaryPartitionKey(indexNames = ["testNameIndex"])
    var testName: String = "",
)

Using the CDK I Created GSI on

        testTable.addGlobalSecondaryIndex(
        GlobalSecondaryIndexProps.builder()
            .indexName("testNameIndex")
            .partitionKey(
                Attribute.builder()
                    .name("testName")
                    .type(AttributeType.STRING)
                    .build()
            )
            .projectionType(ProjectionType.ALL)
            .build())

Then, within my Lambda I am trying to query my DynamoDb table, using a fixed value here testName = A.

My Sample data in the Test table would be like so..

{
"id" : "SomeUUID",
"testName" : "A"
}

    private var client: AmazonDynamoDB = AmazonDynamoDBClientBuilder.standard().build()
    private var dynamoDB: DynamoDB = DynamoDB(client)

Lambda Resolver Snippets...

        val table: Table = dynamoDB.getTable(TABLE_NAME)
        val index: Index = table.getIndex("testNameIndex")
...
        QuerySpec().withKeyConditionExpression("testNameIndex = :testName")
            .withValueMap(ValueMap().withString(":testName", "A"))
        val iterator: Iterator<Item> = index.query(querySpec).iterator()

        while (iterator.hasNext()) {
            logger.info(iterator.next().toJSONPretty())
        }

This is what results in this Error msg: com.amazonaws.services.dynamodbv2.model.AmazonDynamoDBException: Query condition missed key schema element: testName

Am I on the wrong lines here? I know there is some mixing of libs between the 'enhanced' Dynamo sdk and the dynamodbv2 sdk - so if there is a better way of doing this query, I'd love to know!

Thanks!

CodePudding user response：

Your QuerySpec's withKeyConditionExpression is initialized wrong. You need to init it like.

not testNameIndex it should be testName

QuerySpec().withKeyConditionExpression("testName = :testName")
            .withValueMap(ValueMap().withString(":testName", "A"))