How to make an agoric address using cosmjs?

[dckc]

@dtribble asked for a quick example of making an address using the cosmjs library.

[dckc]

The basic outline is:

import { Random } from '@cosmjs/crypto';
import { DirectSecp256k1Wallet } from '@cosmjs/proto-signing';

export const bech32Config = {
  bech32PrefixAccAddr: 'agoric',
 // ...
};

const makeAddr = async () => {
    const seed = Random.getBytes(32);
    const wallet = await DirectSecp256k1Wallet.fromKey(seed, bech32Config.bech32PrefixAccAddr);
    const accounts = await wallet.getAccounts()
    console.log({ accounts });
};

makeAddr().catch(err => console.error(err));

and out comes

{
  accounts: [
    {
      address: 'agoric1pnhkj4ay6qt60pk6t8efmlf5775s8z9a9s0v97',
...

for a complete example including package.json and all that, see https://gist.github.com/dckc/7aa425d6986dd714a76334ff8c0bb9e5

cc @dtribble

[0xpatrickdev]

Hey @dckc, I was looking into this more after reading #6994.

In order to match an address generated by the Keplr client, I found that I needed to use coinType: 564.

Looking here, Agoric's slip44 parameter is 564. In the keplr registry, I see bip44.coinType = 564, but further down I also see an alternativeBIP44s field which contains 118. This leads me to believe both 118 and 564 are valid, but I wanted to see if you could provide more color here.

@tgrecojs also shared this doc which was a helpful resource for me: https://github.com/confio/cosmos-hd-key-derivation-spec/blob/main/README.md

Here is an implementation with coinType: 564 - DirectSecp256k1Wallet does not allow us to specify coinType/hdPath (it uses the ATOM default 118), so below DirectSecp256k1HdWallet is used.

import { Random, Bip39, stringToPath, Slip10RawIndex } from "@cosmjs/crypto";
import { DirectSecp256k1HdWallet } from "@cosmjs/proto-signing";

export const bip44Config = {
  coinType: 564,
};

export const bech32Config = {
  bech32PrefixAccAddr: "agoric",
  // ...,
};

const getAgoricHdPath = (coinType = bip44Config.coinType, account = 0) =>
  stringToPath(`m/44'/${coinType}'/${account}'/0/0`);

// alternative to stringToPath from cosmjs
const getAgoricHdPathWithSlip = (
  coinType = bip44Config.coinType,
  account = 0
) => [
  Slip10RawIndex.hardened(44),
  Slip10RawIndex.hardened(coinType),
  Slip10RawIndex.hardened(account),
  Slip10RawIndex.normal(0),
  Slip10RawIndex.normal(0),
];

const makeAddr = async () => {
  const seed = Random.getBytes(32);
  const mnemonic = Bip39.encode(seed); // fromKey() not supported, convert to mnemonic first
  const wallet = await DirectSecp256k1HdWallet.fromMnemonic(mnemonic.data, {
    prefix: "agoric",
    hdPaths: [getAgoricHdPath()],
  });
  const accounts = await wallet.getAccounts();
  return { seed, mnemonic, accounts };
};

const addressFromMnemonic = async (mnemonic) => {
  const wallet = await DirectSecp256k1HdWallet.fromMnemonic(mnemonic, {
    prefix: bech32Config.bech32PrefixAccAddr,
    hdPaths: [getAgoricHdPath()],
  });
  const accounts = await wallet.getAccounts();
  return accounts;
};

[0xpatrickdev]

Also found DirectSecp256k1HdWallet.generate() which is an abstraction of the Random and Bip39 logic.

import { stringToPath } from "@cosmjs/crypto";
import { DirectSecp256k1HdWallet } from "@cosmjs/proto-signing";

const getAgoricHdPath = (coinType = 564, account = 0) =>
  stringToPath(`m/44'/${coinType}'/${account}'/0/0`);

/**
 * @param length The number of words in the mnemonic (12, 15, 18, 21 or 24).
 */
const makeAddr = async (length = 24) => {
  const wallet = await DirectSecp256k1HdWallet.generate(length, {
    prefix: "agoric",
    hdPaths: [getAgoricHdPath()],
  });
  const accounts = await wallet.getAccounts();
  return { mnemonic: wallet.mnemonic, seed: wallet.seed, accounts };
};

makeAddr().then(console.log).catch(console.error);

[dckc]

Looking here, Agoric's slip44 parameter is 564. In the keplr registry, I see bip44.coinType = 564, but further down I also see an alternativeBIP44s field which contains 118. This leads me to believe both 118 and 564 are valid, but I wanted to see if you could provide more color here.

My rough understanding is that 564 is a coin type we registered, but it's necessary to use 118, the default cosmos coinType, in certain interop situations; in particular, when using a ledger.

It seems to be defined in config.go:

agoric-sdk/golang/cosmos/agoric/config.go

Lines 12 to 13 in 8ccc9cc

	// https://github.com/satoshilabs/slips/blob/master/slip-0044.md
	CoinType = 564

git blame leads to a rename/refactor; the earliest I can trace it back to is 2021-12-09 29535de but I thought I had seen it before that.

@michaelfig did I miss anything?

[0xpatrickdev]

Ok cool, thanks Dan. I tested with a ledger and am seeing that the 118 derivation path is used to generate the address. When imported to Keplr (via "Connect Ledger"), an additional label is added that shows the 118 derivation path is used.



One more question has since surfaced - I am trying to learn more about the account parameter. This doc is leading me to believe that account should always be 0 for Cosmos chains, and addressIndex is what we should be incrementing to get additional accounts. The getAgoricHdPath function would instead look like:

const getAgoricHdPath = (coinType = 564, addressIndex = 0) =>
  stringToPath(`m/44'/${coinType}'/0'/0/${addressIndex}`);

I found a conflicting implementation here, so perhaps this understanding is incorrect. Maybe @kriskowal has some insights.

agoric-sdk/packages/agoric-cli/src/publish.js

Lines 38 to 39 in 3ff8f54

	const hdPath = (coinType = 118, account = 0) =>
	stringToPath(`m/44'/${coinType}'/${account}'/0/0`);

agoric-sdk/packages/agoric-cli/src/publish.js

Lines 263 to 266 in 3ff8f54

	const wallet = await DirectSecp256k1HdWallet.fromMnemonic(mnemonic, {
	prefix: Agoric.Bech32MainPrefix,
	hdPaths: [hdPath(Agoric.CoinType, 0), hdPath(Agoric.CoinType, 1)],
	});