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Area

storage

Describe the bug

This PR: #17525 introduced a new client session note clientId. This means all client sessions created in KC 22 or newer have this note. However, the sessions created by an older version do not have this note.

The persistent user sessions migration is relying on that note to be present and if it is not there, the migration fails with:

..."java.lang.NullPointerException","message":"Cannot invoke \"String.startsWith(String)\" because \"id\" is null"...

as reported here:
#28271 (comment)

Version

25.0.2

Regression

• The issue is a regression

Expected behavior

The migration works even if client sessions were created by an older KC version

Actual behavior

The migration fails

How to Reproduce?

1. Run KC 21 and create some sessions
2. Run KC 25 with enabled persistent-user-sessions feature
3. Migration fails

Anything else?

No response