#substrate #scale #serialization #serde

no-std serde-scale

Serde serializer and deserializer for the SCALE encoding

4 releases

0.2.2 Oct 15, 2020
0.2.1 Oct 8, 2020
0.2.0 Oct 8, 2020
0.1.0 Oct 7, 2020

#825 in Encoding


Used in 2 crates

Zlib license

52KB
1.5K SLoC

Overview

Serializer and deserializer for the SCALE encoding based on serde.

Example

use serde::{Deserialize, Serialize};

#[derive(Debug, Deserialize, PartialEq, Serialize)]
struct Point {
    x: i8,
    y: i8,
}

let point = Point { x: 3, y: 4 };
let deserialized = serde_scale::from_slice(&serde_scale::to_vec(&point).unwrap()).unwrap();
assert_eq!(point, deserialized);

Conformance

Option<bool> is serialized as a single byte according to the SCALE encoding.

Features

no_std is supported by disabling default features.

  • std: Support for std. It is enabled by default.
  • alloc: Support for the alloc crate.

🔖 Features enabled in build dependencies and proc-macros are also enabled for normal dependencies, which may cause serde to have its std feature on when it is not desired. Nightly cargo prevents this from happening with -Z features=host_dep or the following in .cargo/config:

[unstable]
features = ["host_dep"]

For example, this issue arises when depending on parity-scale-codec-derive.

Test

Most tests live in the serde-scale-tests crate (part of the workspace) in order to avoid dependencies enabling serde features.

cargo test --workspace

Contribute

All contributions shall be licensed under the zlib license.

Related projects

parity-scale-codec: Reference Rust implementation

Dependencies

~0.4–1MB
~23K SLoC