SSZ in RUST

From Lighthouse:

Provides encoding (serialization) and decoding (deserialization) in the SimpleSerialize (SSZ) format designed for use in Ethereum 2.0.

Adheres to the Ethereum 2.0 SSZ specification at v0.12.1.

Example

use ssz_derive::{Encode, Decode};
use ssz::{Decode, Encode};

#[derive(PartialEq, Debug, Encode, Decode)]
struct Foo {
    a: u64,
    b: Vec<u16>,
}

fn ssz_encode_decode_example() {
    let foo = Foo {
        a: 42,
        b: vec![1, 3, 3, 7]
    };

    let ssz_bytes: Vec<u8> = foo.as_ssz_bytes();

    let decoded_foo = Foo::from_ssz_bytes(&ssz_bytes).unwrap();

    assert_eq!(foo, decoded_foo);
}

See examples/ for manual implementations of the Encode and Decode traits.

mod decode;
mod encode;

pub use decode::{
    impls::decode_list_of_variable_length_items, Decode, DecodeError, SszDecoder, SszDecoderBuilder,
};
pub use encode::{Encode, SszEncoder};

The number of bytes used to represent an offset.

pub const BYTES_PER_LENGTH_OFFSET: usize = 4;
/// The maximum value that can be represented using `BYTES_PER_LENGTH_OFFSET`.
#[cfg(target_pointer_width = "32")]
pub const MAX_LENGTH_VALUE: usize = (std::u32::MAX >> (8 * (4 - BYTES_PER_LENGTH_OFFSET))) as usize;
#[cfg(target_pointer_width = "64")]
pub const MAX_LENGTH_VALUE: usize = (std::u64::MAX >> (8 * (8 - BYTES_PER_LENGTH_OFFSET))) as usize;

Convenience function to SSZ encode an object supporting

ssz::Encode.

Equivalent to

val.as_ssz_bytes()
pub fn ssz_encode<T>(val: &T) -> Vec<u8>
where
    T: Encode,
{
    val.as_ssz_bytes()
}