Some snippets for self testing on local node of IOST blockchain. Hash and signature functions matched with contract. Feel free to use for testing, and feel free to star🌟if it's useful to you. 🚀

crypto.js

const bs58 = require('bs58');
const { SHA3 } = require('sha3')
const nacl = require('tweetnacl');
const EC = require('elliptic').ec;
const secp = new EC('secp256k1');
const BN = require('bn.js');
const IOST = require('iost')

// equals to `IOSTCrypto.sha3(seed)` in contract
const hash = (seed) => {
    let hash = new SHA3(256);
    let b = hash.update(seed).digest('hex');
    let bytes = Buffer.from(b, 'hex')
    let hashStr = bs58.encode(bytes)
    return hashStr
}

const Algorithm = {
    Ed25519: 2,
    Secp256k1: 1,
};

// sign data with private key
// matches with *signature* in `IOSTCrypto.verify("ed25519", IOSTCrypto.sha3(data), signature, pubkey)`
// or `IOSTCrypto.verify("secp256k1", IOSTCrypto.sha3(data), signature, pubkey)` in contract
const sign = (algo, data, privateKey) => {
    try {
        const seckey = bs58.decode(privateKey);
        const edKP = new IOST.KeyPair(seckey, algo);

        const h = new SHA3(256);
        h.update(data);
        const info = h.digest("binary");

        if (algo == Algorithm.Ed25519) {
            let buffer = Buffer.from(nacl.sign(info, edKP.seckey)).slice(0, 64)
            let sig = bs58.encode(buffer)
            console.log("⛱ sig: ", sig)
            return sig
        } else if (algo == Algorithm.Secp256k1) {
            const secpKey = secp.keyFromPrivate(edKP.seckey);
            const sig = secpKey.sign(info);

            const r = sig.r;
            const n = new BN("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141", 16);
            const s = n.sub(sig.s);

            const b = Buffer.concat([Buffer.from(r.toArray()), Buffer.from(s.toArray())]);
            const sigS = bs58.encode(b)
            console.log("⛱ sig: ", sigS)
            return sigS
        } else {
            throw "algo type error"
        }
    } catch (e) {
        console.log("😈 error: ", e)
    }
}

module.exports = {
    hash,
    sign,

    Algorithm
}