UniFFI Namespace Hierarchy

[arminsabouri]

Currently all of our UniFFI exported types live in one big module/library (not sure what the coloquial python term for this is). All of these classes, functions, etc... are then exported under one namespace (payjoin). Its unclear what exported types belongs to what part of the rust-payjoin api. For example when you from payjoin import UncheckedProposal its unclear if this is a receiver or sender type.

An easy fix would be to re-export specific types as submodules.
I.e
init.py

from payjoin.payjoin_ffi import *

# Re-export specific types into submodules
from . import receiver

__all__ = ['receiver']

receiver.py

from payjoin.payjoin_ffi import UncheckedProposal

__all__ = [UncheckedProposal]

From the application prespective:

from payjoin.receiver import UncheckedProposal

[DanGould]

If this is to be done I ask that the names match payjoin i.e. 'receive' rather than 'receiver'

[Mshehu5]

can I handle this issue ?
@DanGould

[spacebear21]

Go for it @Mshehu5 !

[arminsabouri]

Update:
Creating Python submodules would improve the Python interface, but there are two core issues:

• conflicting exported names across different rust sub modules
• Lack of a consistent pattern for other (future) language bindings.

A more future proof approach is to refactor the .udl file to define a clear namespace hierarchy. Ideally, this hierarchy should mirror the module structure of the payjoin crate as closely as possible.

[Mshehu5]

I've been working on updating the UDL (UniFFI Definition Language) file for the Rust-based Payjoin-ffi library to define a clear namespace hierarchy, but I'm encountering persistent parse errors.

What I've tried:

1. Created minimal test files: Even a simple test UDL file with basic types encounters the same parsing error.
2. Cleaned build artifacts: Removed cached build files to ensure clean compilation.
3. Verified UDL syntax: Read through the [UniFFI UDL documentation] to ensure the UDL syntax matches what's stated in the official docs.

Current error:

Error parsing the IDL. Text remaining to be parsed is:
namespace payjoin_ffi {
...
}
Caused by:
    parse error

The error occurs at the very beginning of the file, suggesting a fundamental issue with how UniFFI is parsing the UDL.

Questions:

1. Could the build configuration in generate_linux.sh be causing conflicts with the UDL parsing?

Any suggestions on how to resolve this persistent parsing issue would be greatly appreciated.

[DanGould]

I think we're stuck with 1 flat namespace for now according to this issue. A hierarchical namespace would be nice to have but It seems unsupported upstream for the time being mozilla/uniffi-rs#1849

It might be possible to wrangle python to fit a hierarchical namespace, but then we'd have to repeat that hack for each language, and I'd rather wait til it's supported by the generator before we add the complexity.

In order to tackle this issue from the generator you may need to edit the upstream uniffi-rs repo.

[arminsabouri]

It might be possible to wrangle python to fit a hierarchical namespace, but then we'd have to repeat that hack for each language, and I'd rather wait til it's supported by the generator before we add the complexity.

Agree with this. Marking this as wont fix. If its ever fixed upstream we can revisit this.

[spacebear21]

Closing as wontfix