Autonomi FFI — Python bindings

Direct-network, daemon-less Autonomi client for Python, generated by UniFFI from the ant-ffi Rust crate — the same compiled library that backs the Swift and Kotlin mobile SDKs. Unlike antd (which talks to a running antd daemon over REST/gRPC), this embeds the network client in-process, exactly like the mobile bindings.

Async Client methods are real async def — they run on Rust's tokio runtime and bridge to asyncio, so await client.data_put_public(...) works from plain asyncio with no extra event-loop setup.

Package name. The distribution is ant-sdk (matches this repo) — a working title, distribution name only: the import name is ant_ffi, fixed by the UniFFI crate namespace (pip install ant-sdk, then import ant_ffi). If a product-level rename happens, the PyPI project will be deleted and recreated under the new name. Track: V2-880.

Layout

python/
├── ant_ffi/
│   ├── __init__.py         # re-exports the generated surface
│   ├── ant_ffi.py          # generated by uniffi-bindgen (do not edit)
│   └── libant_ffi.dylib    # bundled native lib (per-platform; not committed)
├── examples/
│   └── upload_download_demo.py
├── tests/
│   └── test_smoke.py       # offline: import + version + address derivation
├── pyproject.toml
└── README.md

The generated ant_ffi.py and the bundled native library are build outputs — regenerate them with ffi/scripts/build.sh (which now includes a Python step).

Build the bindings

cd ffi/rust && cargo build --release -p ant-ffi
./target/release/uniffi-bindgen generate \
    --library target/release/libant_ffi.dylib \
    --language python --out-dir ../python/ant_ffi/
cp target/release/libant_ffi.dylib ../python/ant_ffi/   # or .so / .dll

(ffi/scripts/build.sh does all of the above alongside the C#/Kotlin/Swift steps.)

Build & check a wheel

This is a wheel-only distribution. sdist is deliberately blocked — a source tarball would embed this host's native library under a platform-neutral name — and the wheel build refuses to run unless the generated module and native library are staged (otherwise the wheel would install cleanly and fail on first import). Build and verify with:

cd ffi/python && python3 -m build --wheel
../scripts/check-python-wheel.sh   # installs into a throwaway venv + imports

Smoke test (offline, no network)

cd ffi/python && python3 tests/test_smoke.py

Upload/download demo (needs a devnet)

Start a local devnet (writes ~/.ant-dev/devnet-manifest.json):

cd ant-node && cargo run --release --bin ant-devnet -- \
    --preset small --enable-evm --manifest ~/.ant-dev/devnet-manifest.json

Then run the round-trip demo — connect from the manifest, upload a file (the manifest wallet pays inside ant-core), download it back, verify byte-identical:

cd ffi/python && python3 examples/upload_download_demo.py

Progress callbacks & threading

_with_progress / download_*_to_file methods take a ProgressListener (subclass it, implement on_progress). Callbacks arrive on a Rust/tokio worker thread, not the asyncio event loop. asyncio is not thread-safe, so to touch event-loop state from a callback, hop back with loop.call_soon_threadsafe(...). Keep callbacks quick — events flow through a bounded channel and a slow callback backpressures the transfer.