Removing a version does not remove associated labels

[Arun kumar Ram <ar...@adobe.com.INVALID>]

Hi All,

We have encountered a behavior of versionStorage and versionLabels which I think is bug.

Current behavior:


  1.  Create a node and make it versionable
  2.  Now create more than two versions (for example two version is  1.0 and 1.1 respectively)
  3.  Now add label at version 1.0 via VersionHistory Object (for example label is Label_1.0)
  4.  Now remove the version 1.0 via calling removeVersion(1.0) method of VersionHistory object
  5.  Now call method hasVersionLabel(Label_1.0)  of versionHistory . its now returning true.

Expected behaviour:
Call to the hasVersionLabel(Label_1.0)  of versionHistory should not return true because version associated with label does not exist. And removing the version should remove associated labels.

If we say that hasVersionLabel(Label_1.0)  of versionHistory returning true is expected behavior because label is not removed. Then call to the function getVersionByLabel(Label_1.0) of versionHistory will throw VersionException because version does not exist. So the repository goes into inconsistent state.

Solution proposal:
One of the solution can be that whenever consumer of  versionHistory removes the version , he should be forced to remove the versionLabel first by throwing LabelExistException

Another solution can be we should remove version label whenever user removes the version.

Current behavior of versionLabel node:
1) it keeps mapping of version and labels
2) labels name should be unique for node.
3) one version can have multiple labels


Sample test case is added in patch of jira OAK-9891
I want to know what can justify this behavior.

I want to know what are the thoughts of communities regarding this .
1) if we agree on bug , what can be best solution from above suggested approach. Any other suggestions.
2) if we disagree, what is reasoning.

Rerence docs: https://developer.adobe.com/experience-manager/reference-materials/spec/jcr/2.0/15_Versioning.html

[1] https://issues.apache.org/jira/browse/OAK-9891

Thanks,
Arun Kumar Ram