[OPEN-ILS-DEV] IDL is not backward compatible?

[Jason Stephenson]

On 2/19/19 7:54 PM, Ken Cox wrote:
> Dan Wells: Good suggestion re: opensrf.open-ils.system.ils_version.  I
> will think more about it.  For now, disabling caching for the
> fm_IDL.xml request will have the same effect as querying the version
> on every login. It would help if auth tokens got invalidated during
> server upgrades; does anyone know whether that's true?

If you restart memcached, it will disable all authtokens by clearing
where they are stored.  We typically do upgrades starting on Sunday
nights over long weekends, and install O/S updates and reboot the VMs
and servers as part of the process. This clears pretty much everything
from the servers' caches.

As for the rest of the conversation, I don't have much to add, except
that I think it would be nice if there were an option to use a hash
(JSON struct) of field/value pairs for objects over the gateways.  I
believe that the XML-RPC gateway works that way more or less.

The Perl and JavaScript fieldmapper objects have methods, to_bare_hash
and from_bare_hash, that let you dump an object's properties to a hash
and create an object from such a hash. With these methods, the order of
the fields doesn't matter.  Unless a new field is required, you could
still create a functioning object even when the IDL is out of sync
between the client and the server.  This would have the drawback of
sending more data over the wire.

Good luck,
Jason