Page History

...

Discussion thread: here

JIRA: TBD here

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

...

In this KIP we propose to bump each of these records to a flexible version and backport this to earlier releases, specifically 3.0.3, 3.1.3, 3.2.4, 3.3.3, and 3.4.1 (note: these minor versions may never be released). We will also apply this to 3.5 if the patch is merged to trunk before the code freeze date. Backporting this patch to earlier releases is acceptable because the change is small and is very low risk. One limitation is that we will be unable to downgrade to a version lower than 3.X. We will mention in future release notes where a new record type or a new field is introduced that we can only downgrade to the aforementioned versions. Note that once a new tagged field is introduced in a later version, that version can never be downgraded to below the listed versions.

We will only deserialize with the flexible version but serialize with the highest known non-flexible version. This is because users upgrading to one of these versions may want to downgrade but if we serialize with the flexible version they won't be able to downgrade back to an earlier version. Deserializing a flexible version to a non-flexible version will fail.

...