On 28.7.16 11:03 , Michael Marth wrote:
Hi Bertrand,
I believe this is unchartered territory.
It is (usually?) safe to assume that the persistence state written by Oak version
X can be read and modified by version Y if Y > X.
The TarMK variants have safeguards built in to fail early without
corrupting anything if the persistent version doesn't match the code
version.
Michael
However: version Y might introduce new features or perform changes on the
state’s format, etc. When such a change is introduced it is not considered that
version X might still operate on the same state.
For many values of X and Y your setup would probably work in practice. But to
my knowledge there is no formal way to find out which values of X and Y are
safe - at least so far.
Michael
On 28/07/16 10:45, "Bertrand Delacretaz" <[email protected]> wrote:
Hi,
On Thu, Jul 28, 2016 at 10:23 AM, Stefan Egli <[email protected]> wrote:
...we could introduce a concept of
'compatibility levels' which are a set of features/behaviours that a
particular oak version has and that application code relies upon....
Good timing, I have a related question about multiple client apps
connecting to the same Oak backend.
Say I have to Java apps A and B which use the same Oak/Mongo/BlobStore
configuration, are there defined requirements as to the Oak library
versions or other settings that A and B use?
Do they need to use the exact same versions of the Oak bundles, and
are violations to that or to other compatibility requirements
detected?
-Bertrand
