PyO3
Rust bindings for Python. This includes running and interacting with python code from a rust binaries as well as writing native python modules.
A comparison with rust-cpython can be found in the guide.
Usage
PyO3 supports python 2.7 as well as python 3.5 and up. The minimum required rust version is 1.30.0-nightly 2018-08-18.
You can either write a native python module in rust or use python from a rust binary.
On some OSs, you need some additional packages.
E.g. if you are on Ubuntu18.04, please run
sudo apt install python3-dev python-dev
Using rust from python
PyO3 can be used to generate a native python module.
Cargo.toml
:
[package]
name = "string-sum"
version = "0.1.0"
[lib]
name = "string_sum"
crate-type = ["cdylib"]
[dependencies.pyo3]
version = "0.6.0"
features = ["extension-module"]
src/lib.rs
# #![allow(unused_variables)] #fn main() { # extern crate pyo3; use pyo3::prelude::*; use pyo3::wrap_pyfunction; #[pyfunction] /// Formats the sum of two numbers as string fn sum_as_string(a: usize, b: usize) -> PyResult<String> { Ok((a + b).to_string()) } /// This module is a python module implemented in Rust. #[pymodule] fn string_sum(py: Python, m: &PyModule) -> PyResult<()> { m.add_wrapped(wrap_pyfunction!(sum_as_string))?; Ok(()) } #}
On windows and linux, you can build normally with cargo build --release
. On macOS, you need to set additional linker arguments. One option is to compile with cargo rustc --release -- -C link-arg=-undefined -C link-arg=dynamic_lookup
, the other is to create a .cargo/config
with the following content:
[target.x86_64-apple-darwin]
rustflags = [
"-C", "link-arg=-undefined",
"-C", "link-arg=dynamic_lookup",
]
For developing, you can copy and rename the shared library from the target folder: On macOS, rename libstring_sum.dylib
to string_sum.so
, on windows libstring_sum.dll
to string_sum.pyd
and on linux libstring_sum.so
to string_sum.so
. Then open a python shell in the same folder and you'll be able to import string_sum
.
To build, test and publish your crate as python module, you can use pyo3-pack or setuptools-rust. You can find an example for setuptools-rust in examples/word-count, while pyo3-pack should work on your crate without any configuration.
Using python from rust
Add pyo3
this to your Cargo.toml
:
[dependencies]
pyo3 = "0.5"
Example program displaying the value of sys.version
:
# extern crate pyo3; use pyo3::prelude::*; use pyo3::types::IntoPyDict; fn main() -> PyResult<()> { let gil = Python::acquire_gil(); let py = gil.python(); let sys = py.import("sys")?; let version: String = sys.get("version")?.extract()?; let locals = [("os", py.import("os")?)].into_py_dict(py); let user: String = py.eval("os.getenv('USER') or os.getenv('USERNAME')", None, Some(&locals))?.extract()?; println!("Hello {}, I'm Python {}", user, version); Ok(()) }
Examples and tooling
- examples/word-count Counting the occurrences of a word in a text file
- hyperjson A hyper-fast Python module for reading/writing JSON data using Rust's serde-json
- rust-numpy Rust binding of NumPy C-API
- html-py-ever Using html5ever through kuchiki to speed up html parsing and css-selecting.
- pyo3-built Simple macro to expose metadata obtained with the
built
crate as aPyDict
- point-process High level API for pointprocesses as a Python library
- autopy A simple, cross-platform GUI automation library for Python and Rust.
- orjson Fast Python JSON library