[Mailman-Developers] Handling additions to REST API in client side

[Simon Hanna]

On 12/28/2017 06:19 PM, Mark Sapiro wrote:
> On 12/28/2017 08:33 AM, Simon Hanna wrote:
>
>> * New keys (and values) can be added anytime
>>
>> This would make things like exposing new stuff easy. Clients that don't
>> know about a field can just ignore it.
>
> But that doesn't address the original issue which is that when a new
> key/value is added and a client is updated to use it, the client has no
> way to require a core API that provides it.
>
Up until now I was under the impression that the clients 
(Postorius/Hyperkitty) always require the latest version of core.
Do we really want to add the burden of having to care for different api 
versions in the clients?

If we would start from scratch something like http://www.coreapi.org/ 
might be feasible,
adding that now would more or less require a complete rewrite of Postorius.

In my view backward compatibiliy should be applied so that old clients 
can still access newer versions of core.
I don't think it's a good idea to require Postorius to be compatible 
with older(all?) versions of core.