@owstack/wallet-service/base-service/lib/model/copayer.js

A service for multisignature HD wallets

const owsCommon = require('@owstack/ows-common');
const AddressManager = require('./addressmanager');
const Constants = owsCommon.Constants;
const sjcl = require('sjcl');
const lodash = owsCommon.deps.lodash;
const $ = require('preconditions').singleton();

const FIELDS = [
    'version',
    'createdOn',
    'xPubKey',
    'id',
    'name',
    'requestPubKeys',
    'customData',
    'addressManager'
];

class Copayer {
    constructor(context) {
    // Context defines the coin network and is set by the implementing service in
    // order to instance this base service; e.g., btc-service.
        context.inject(this);
    }
}

Copayer.create = function (context, opts) {
    opts = opts || {};
    $.checkArgument(opts.xPubKey, 'Missing copayer extended public key')
        .checkArgument(opts.requestPubKey, 'Missing copayer request public key')
        .checkArgument(opts.signature, 'Missing copayer request public key signature');

    opts.copayerIndex = opts.copayerIndex || 0;

    const x = new Copayer(context);

    x.version = 2;
    x.createdOn = Math.floor(Date.now() / 1000);
    x.xPubKey = opts.xPubKey;
    x.id = Copayer._xPubToCopayerId(x.xPubKey);
    x.name = opts.name;
    x.requestPubKeys = [{
        key: opts.requestPubKey,
        signature: opts.signature,
    }];

    const derivationStrategy = opts.derivationStrategy || Constants.DERIVATION_STRATEGIES.BIP45;
    if (AddressManager.supportsCopayerBranches(derivationStrategy)) {
        x.addressManager = AddressManager.create({
            derivationStrategy: derivationStrategy,
            copayerIndex: opts.copayerIndex,
        });
    }

    x.customData = opts.customData;

    return x;
};

Copayer.fromObj = function (context, obj) {
    const x = new Copayer(context);

    lodash.each(FIELDS, function (k) {
        x[k] = obj[k];
    });

    if (obj.addressManager) {
        x.addressManager = AddressManager.fromObj(obj.addressManager);
    }

    return x;
};

Copayer.prototype.toObject = function () {
    const self = this;
    const x = {};
    lodash.each(FIELDS, function (k) {
        x[k] = self[k];
    });
    return x;
};

Copayer._xPubToCopayerId = function (xpub) {
    const hash = sjcl.hash.sha256.hash(xpub);
    return sjcl.codec.hex.fromBits(hash);
};

Copayer.prototype.createAddress = function (wallet, isChange) {
    $.checkState(wallet.isComplete());

    const path = this.addressManager.getNewAddressPath(isChange);
    const address = new this.ctx.Address().derive(wallet.id, wallet.addressType, wallet.publicKeyRing, path, wallet.m, wallet.networkName, isChange);
    return address;
};

module.exports = Copayer;