ListUsers API Improvement

[flex-seongbok]

Please consider adding multiple UserTypeFilter support on listUsers API to implement local index introduced in Search With Permissions Option.2

Sample Authorization Model

model
  schema 1.1

type user

type group
  relations
    define member: [ user ]

type org
  relations
    define member: [ user ]

type file
  relations
    define viewer: [ org#member, group#member, user ]

The reason why I prefer local index is the characteristic of my application.
user - group - org relations are changing somewhat frequently and objects could be thousands, billions even millions.
In this circumstance if I use listUsers that only returns user to build local index the application will explode due to updating millions local index.
Imagine a scenario that org has millions file that shared to all the org member through org#member relation.
If one user is added to a org then all the local index for million files should be updated to add single user.

This can be mitigated building local index using UserSet not User.
Yes I can use current listUsers to list UserSet but unfortunately file can be shared to user directly too.

For now listUsers API returns either the user or except the user.
If listUsers API supports multiple UserTypeFilter and stop expanding UserSet when it meets any of the passed UserTypeFilter this can be solved.

Summary

1. Current Limitation:
   The listUsers API currently returns either User or UserSet except User

2. Proposed Enhancement:
   Add support for multiple UserTypeFilter options in the listUsers API.

3. Desired Behavior:
   The API should stop expanding UserSet when it meets any of the passed UserTypeFilters.

4. Use Case:
   This would allow to build a local index using UserSets instead of individual User, which is more efficient for scenarios where

• User-group-org relations change frequently
• There are a large number of objects (thousands to millions)
• Direct user sharing is also possible

5. Problem it Solves:
   It addresses the issue of having to update millions of local index entries when a single user is added to an org, especially in cases where files are shared with all org members.

[flex-seongbok]

It doesn't look easy if relations have intersection or difference... hmm