Lib.rs

kona-serde

Serde related helpers for kona.

Graceful Serialization

This crate extends the serialization and deserialization functionality provided by alloy-serde to deserialize raw number quantity values.

This issue arose in u128 toml deserialization where deserialization of a raw number fails. This rust playground demonstrates how toml fails to deserialize a native u128 internal value.

With kona-serde, tagging the inner u128 field with #[serde(with = "kona_serde::quantity")], allows the u128 or any other type within the following constraints to be deserialized by toml properly.

These are the supported native types:

• bool
• u8
• u16
• u32
• u64
• u128

Below demonstrates the use of the #[serde(with = "kona_serde::quantity")] attribute.

use serde::{Serialize, Deserialize};

/// My wrapper type.
#[derive(Debug, Serialize, Deserialize)]
pub struct MyStruct {
    /// The inner `u128` value.
    #[serde(with = "kona_serde::quantity")]
    pub inner: u128,
}

// Correctly deserializes a raw value.
let raw_toml = r#"inner = 120"#;
let b: MyStruct = toml::from_str(raw_toml).expect("failed to deserialize toml");
println!("{}", b.inner);

// Notice that a string value is also deserialized correctly.
let raw_toml = r#"inner = "120""#;
let b: MyStruct = toml::from_str(raw_toml).expect("failed to deserialize toml");
println!("{}", b.inner);

Provenance

This code is heavily based on the alloy-serde crate.