UpdateItemEnhancedRequest for null version number with ignoreNulls(true) results into ConditionalCheckFailedException

[onkar27]

Describe the issue

When we use ignoreNulls(true) feature while doing table.updateItem understanding that it will ignore all null fields to update it in db. But it looks like it's not working as expected for dynamo db version field, when my object contain all required fields like primary hash key, and sort key and version number as null, it's throwing ConditionalCheckFailedException.

Steps to Reproduce

Where version number field is declared as below.

    @Getter(onMethod_ = {@DynamoDbVersionAttribute})
    private Long version;

customDynamoDbBeanObject.version(null); 
dynamoDbTable.updateItem(UpdateItemEnhancedRequest.builder(CustomDynamoDbBean.class)
             .item(customDynamoDbBeanObject)
             .ignoreNulls(true)
             .build());

Current Behavior

It's throwing ConditionalCheckFailedException.

Your Environment

• AWS Java SDK version used: AwsJavaSdk-DynamoDb-Enhanced = 2.0;
• JDK version used: JDK8 = 1.0;
• Operating System and version: Linux

[debora-ito]

@onkar27 I don't think version can be null by definition, once you start using it.

The idea of having a version attribute is to make sure the version number on the server side has not changed since you retrieved the item. If the version does not match it means that the item was modified and you have a stale version.

Specifying version = null and say to ignore it when you try to update the item defeats the purpose of optimistic locking. You should provide a version number before updating an item. So getting a ConditionalCheckFailedException is expected in this case. Does it make sense?

[onkar]

Hi @debora-ito, you probably want to tag @onkar27 instead of me.

[debora-ito]

Sorry for the confusion 😬

[onkar27]

@debora-ito Thanks for reply, yeah I understand it when I'm reading for optimistic locking in dynamoDB. I think in the documentation of ignoreNulls(true) here, we should have it mentioned for version fields ignoreNulls feature doesn't apply.

[bufistov]

You can disable "Versioning" extension in mapper to bypass locking:

DynamoDbEnhancedClient.builder().dynamoDbClient(DynamoDbClient.create())
.extensions(Collections.emptyList()) // Disable version locking
.build()