Implement ListRelations as a single network request instead of multiple Check requests

[gurleensethi]

Checklist

• I agree to the terms within the OpenFGA Code of Conduct.

Describe the problem you'd like to have solved

While investigating the openfga/go-sdk source code to address some performance issues, I discovered that the ListRelations function is actually executing multiple parallel Check requests (see call to BatchCheck and multiple requests within BatchCheck).

This approach becomes problematic when managing a high number of relations, such as 300, for several reasons:

1. There is a maximum limit on concurrent Check requests that can be executed, although this can be mitigated by increasing the MaxParallelRequests setting.
2. The substantial overhead from numerous parallel network requests contributes to decreased performance (this is huge).
3. Since all relations involve the same User + Object, each request repeatedly retrieves the corresponding tuple from the database (can be mitigated to some extent by enabling node caching).

Describe the ideal solution

Ideally, calling ListRelations (and even CheckBatch for that matter) should result in only a single call to the OpenFGA server, this should help a lot with performance.

Alternatives and current workarounds

No response

Additional context

No response

[rhamzeh]

Hi @gurleensethi - thanks for raising this. It's already on our Roadmap: https://github.com/orgs/openfga/projects/1?pane=issue&itemId=28481432

The SDKs will switch the underlying method being used once it is ready on the server

[aaguiarz]

Hi @gurleensethi

Can you expand on the use case for requesting 300 relations?

If you prefer to discuss in a quick call you can reach out to me at andres.aguiar @ openfga.dev