serde-pyobject

PyO3's PyAny as a serde data format

Usage

Serialize T: Serialize into &'py PyAny:

use serde::Serialize;
use pyo3::{Python, Bound, types::{PyAny, PyAnyMethods, PyDict}};
use serde_pyobject::{to_pyobject, pydict};

#[derive(Serialize)]
struct A {
    a: u32,
    b: String,
}

Python::with_gil(|py| {
    let a = A { a: 1, b: "test".to_string() };
    let obj: Bound<PyAny> = to_pyobject(py, &a).unwrap();
    assert!(obj.eq(pydict! { py, "a" => 1, "b" => "test" }.unwrap()).unwrap());
});

Deserialize &'py PyAny into T: Deserialize<'de>:

use serde::Deserialize;
use pyo3::{Python, Bound, types::{PyAny, PyAnyMethods, PyDict}};
use serde_pyobject::{from_pyobject, pydict};

#[derive(Debug, PartialEq, Deserialize)]
struct A {
    a: u32,
    b: String,
}

Python::with_gil(|py| {
    let a: Bound<PyDict> = pydict! { py,
      "a" => 1,
      "b" => "test"
    }
    .unwrap();
    let a: A = from_pyobject(a).unwrap();
    assert_eq!(a, A { a: 1, b: "test".to_string() });
});

Mapping between Python and serde data model

serde data model	PyO3 type	Rust	Python
i8, i16, i32, i64, isize, u8, u16, u32, u64, usize	PyLong	123	123
f32, f64	PyFloat	1.0	1.0
bool	PyBool	true	true
char, string	PyString	'a', "test"	"a", "test"
option	PyAny 1	None, Some(1)	None, 1
unit	PyTuple	()	()
unit struct	PyTuple	struct Unit	()
unit variant	PyDict	E::A in enum E { A, B }	"A"
newtype struct	PyDict	A(32) of struct A(u8)	32
newtype variant	PyDict	E::N(41) of enum E { N(u8) }	{ "N": 41 }
seq	PyList	vec![1, 2, 3]	[1, 2, 3]
tuple	PyTuple	(1, "test")	(1, "test")
tuple struct	PyDict	T(1, "a") of struct T(u32, String)	(1, "a")
tuple variant	PyDict	E::S(1, 2) of enum E { S(u8, u8) }	{ "S": (1, 2) }
map	PyDict	hashmap!{ "a".to_string() => 1, "b".to_string() => 2 }	{ "a": 1, "b": 2 }
struct	PyDict	A { a: 1, b: "test" } of struct A { a: u32, b: String }	{ "a": 1, "b": "test"}
struct variant	PyDict	E::S { r: 1, g: 2, b: 3 } of enum E { S { r: u8, g: u8, b: u8 } }	{ "S": { "r": 1, "g": 2, "b": 3 } }

License

© 2023 Jij Inc.

This project is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)

at your option.

Footnotes

1. Some(value) is serialized as value ↩