Use existing values to support partial updates on alerts and actions

[mikecote]

Right now you need all the attributes part of the AAD on update.

[elasticmachine]

Pinging @elastic/kibana-stack-services (Team:Stack Services)

[pmuellr]

So you're suggesting the update endpoints of alerts/actions should support a 'merge' (update, not replace) option?

I think that makes sense, but our current 'overwrite' story (you need to provide all the attributes, and then weirdly, we do an update, not overwrite, on the SO) is very secure, AAD wise. This seems like it may change that story a bit.

[mikecote]

@pmuellr Hmm, good point, maybe we shouldn't do this because of AAD. It would probably go against why we're using AAD in the first place. We will have to live with some weirdness like this (#49320 (comment)) by keeping what we have now, which makes sense I guess.

[pmuellr]

Ya, I have this sneaking suspicion it may break AAD, or the security it provides anyway.

Since we currently only support 'overwrite' (but it's really an SO update), and will always need to, in case someone wants to "delete" an attribute by setting it to null, I think we'll need a separate mode for 'update' (option provide on update request), and so seems like something we can defer till we see a requirement. Eg, I can see how our current API could be extended in the future to provide this capability.

Do we have a requirement for this from someone?

[mikecote]

None at this time, it was more a quick thought I had that seemed redundant but as soon as "breaking AAD" was brought up, made this issue not recommended. I will close for now and we can revisit in the future if necessary.