cip14 fingerprint

[Sbcdn]

#359

[SmaugPool]

The code already exists in Pallas: https://github.com/txpipe/pallas/blob/main/pallas-crypto/src/hash/hasher.rs.

You just have to add:

common_hasher!(160);

at https://github.com/txpipe/pallas/blob/1482303616e9ba68f322eceb9ed03118efee28d5/pallas-crypto/src/hash/hasher.rs#L109 and some comments in the header, then you can do something like:

use pallas::crypto::hash::{Hash, Hasher};

fn asset_fingerprint(policy: &ByteVec, asset: &ByteVec) -> String {
    let mut hasher = Hasher::<160>::new();
    hasher.input(policy);
    hasher.input(asset);
    bech32::encode(
        &"asset".to_string(),
        hasher.finalize().to_base32(),
        bech32::Variant::Bech32,
    )
    .unwrap()
}

Likely returning a Result instead of the unwrap here.

[SmaugPool]

I think we might also want the fingerprint in the MintRecord struct too, but this kind of leads to duplicates, so I'm not sure what's the best option here.