in that one you have to write two relationships per ban

gotcha. i'm gonna wrap up for the day. thanks yall. It's been extremely helpful

have a good one, let us know if you run into any other modeling challenges

So Friday we were talking about adding attributes at the platform level in SpiceDB. It was working well until I got stuck on this:

/** An active investment has not been canceled */
    permission active_investment = investment - platform->canceled
    /** A deal participant is an account sponsor of a deal's active investment */
    permission participant = active_investment->account_sponsor

I can't do

permission->relation

. But I also can't nest arrows. So I think I need to model it differently somehow.....?

yeah, you likely need an intermediate permission

that's the workaround for nested arrows

thing->platform->canceled

would become

thing->platform_canceled

, and then

platform_canceled = platform->canceled

does that help?

So I've already got the intermediate permissions in

account_sponsor

, but it doesn't work for the thing I'm trying to model... which looks like

(investment - platform->canceled)->account->sponsor

can you share a playground link?

i think you likely have a type mismatch

oooh, yeah interesting

and your subject is a user?

Yep

In a later iteration subject may also be a 3rd party application

yeah you need to find a way to manipulate downstream users when the investment being canceled relationship changes

all of your permissions should terminate in users if that's your subject

Yeah, the issue is permissions are the only way I can represent a derived relation

yes if we supported computed permissions on the LHS of an arrow that would be an alternative, but that's a pretty big deviation from the zanzibar paper and it will tank performance of distributing subproblems

Hmm

let me think about it for a second

I think I will return to my previous (simplified) model for the time being. It was tricky getting the data sync to behave but I appear to have traded one problem for another.

can you cancel the investment?

like... at the investment level

Yeah, we don't do deletes is the thing

what about something like that?

Not quite, unfortunately