https://github.com/omerbenamram/pyo3-file
A small helper library for working with python file-like objects with rust.
https://github.com/omerbenamram/pyo3-file
Last synced: 2 months ago
JSON representation
A small helper library for working with python file-like objects with rust.
- Host: GitHub
- URL: https://github.com/omerbenamram/pyo3-file
- Owner: omerbenamram
- Created: 2019-05-19T16:37:23.000Z (about 7 years ago)
- Default Branch: master
- Last Pushed: 2026-02-08T18:03:03.000Z (4 months ago)
- Last Synced: 2026-02-08T23:58:04.577Z (4 months ago)
- Language: Rust
- Size: 132 KB
- Stars: 47
- Watchers: 2
- Forks: 13
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
Awesome Lists containing this project
- awesome-rust-python - pyo3-file - Helper library for working with Python file-like objects with Rust. (Build Tools & Frameworks)
README
# PyO3-File
This is a small utility library to facilitate working with python file-like objects with rust.
## Example
An example use case for this is when a file is opened in python, and needs to be passed to a rust library.
We could support both by introspecting the `PyObject`, and pick the correct behavior.
We would like this to work:
```python
from path_or_file_like import accepts_path_or_file_like
def main():
# should open `some_file.txt`.
accepts_path_or_file_like("./some_file.txt")
# should read from the python handle.
f = open('./some_file.txt')
accepts_path_or_file_like(f)
```
We could use `pyo3_file` to extend an existing a `pyo3` module.
```rust
use pyo3_file::PyFileLikeObject;
use pyo3::types::PyString;
use pyo3::prelude::*;
use pyo3::wrap_pyfunction;
use std::io::Read;
use std::fs::File;
/// Represents either a path `File` or a file-like object `FileLike`
#[derive(Debug)]
enum FileOrFileLike {
File(String),
FileLike(PyFileLikeObject),
}
impl<'py> FromPyObject<'py> for FileOrFileLike {
fn extract_bound(ob: &Bound<'py, PyAny>) -> PyResult {
// is a path
if let Ok(string) = ob.extract::() {
return Ok(FileOrFileLike::File(string));
}
// is a file-like
let f = PyFileLikeObject::py_with_requirements(ob.clone(), true, false, true, false)?;
Ok(FileOrFileLike::FileLike(f))
}
}
#[pyfunction]
/// Opens a file or file-like, and reads it to string.
fn accepts_path_or_file_like(path_or_file_like: FileOrFileLike) -> PyResult {
match path_or_file_like {
FileOrFileLike::File(s) => {
println!("It's a file! - path {}", s);
let mut f = File::open(s)?;
let mut string = String::new();
f.read_to_string(&mut string)?;
Ok(string)
}
FileOrFileLike::FileLike(mut f) => {
println!("Its a file-like object");
let mut string = String::new();
f.read_to_string(&mut string)?;
Ok(string)
}
}
}
#[pymodule]
fn path_or_file_like(_py: Python, m: &PyModule) -> PyResult<()> {
m.add_wrapped(wrap_pyfunction!(accepts_path_or_file_like))?;
Ok(())
}
# fn main() {}
```