@coolwallet/evm

CoolWallet EVM Compatible SDK

Typescript library with support for the integration of EVM compatible chain for third party application, include the functionalities of generation of addresses and signed transactions.

Install

npm install @coolwallet/evm

Usage

import EVM from '@coolwallet/evm';
import { crypto } from '@coolwallet/core';
import { createTransport } from '@coolwallet/transport-web-ble';

// Select the chain
const chainId = 137; // Polygon Mainnet
const evm = new EVM(chainId);

const transport = await createTransport();

const { privateKey: appPrivateKey } = crypto.key.generateKeyPair();

const appId = 'appId that had been registered by wallet';

const addressIndex = 0;

const address = await evm.getAddress(transport, appPrivateKey, appId, addressIndex);

const transaction = {
  nonce: '0x21d',
  gasPrice: '0x59682f00',
  gasLimit: '0x5208',
  to: '0x81bb32e4A7e4d0500d11A52F3a5F60c9A6Ef126C',
  value: '0x5af3107a4000',
  data: '0x00',
};

const signTxData = {
  transport,
  appPrivateKey,
  appId,
  transaction,
  addressIndex,
};

const normalTx = await evm.signTransaction(signTxData);

const signTxData = {
  transport,
  appPrivateKey,
  appId,
  transaction,
  addressIndex,
};

const erc20Transaction = {
  nonce: '0x85',
  gasPrice: '0x23a427985a',
  gasLimit: '0x72c2',
  to: '0xe41d2489571d322189246dafa5ebde1f4699f498',
  value: '0x0',
  data: '0x00',
  option: {
    symbol: 'USDT',
    unit: '6',
  },
};

const erc20SignTxData = {
  transport,
  appPrivateKey,
  appId,
  transaction: erc20Transaction,
  addressIndex,
};

const erc20Tx = await evm.signERC20Transaction(erc20SignTxData);

Methods

getAddress

Description

The address generated is compatible to BIP44 with account and change set to 0, which means calling getAddress with addressIndex = i will get the address of folllowing BIP44 path:

m/44'/60'/0'/0/{i}

In the design of current hardware, we only support path m/44'/60'/0'/0/{i} for speed optimization. This might change in the future and we will then open a more general interface to deal with custom path.

async getAddress(
    transport: types.Transport,
    appPrivateKey: string,
    appId: string,
    addressIndex: number
): Promise<string>

Arguments

Arg	Description	Type	Required
transport	Object to communicate with CoolWallet device	Transport	True
appPrivateKey	Private key for the connected application	string	True
appId	ID for the connected application	string	True
addressIndex	The from address index in BIP44 derivation	number	True

signTransaction

Description

Sign Ethereum Transaction. If the transaction has non-empty data field, the card will display SMART instead of transfering amount.

async signTransaction(signTxData: types.signTx): Promise<string>

signTx Arguments

Arg	Description	Type	Required
transport	Object to communicate with CoolWallet device	Transport	True
appPrivateKey	Private key for the connected application	string	True
appId	ID for the connected application	string	True
transaction	Essential information/property for Ethereum Transaction	Transaction	True
addressIndex	The from address index in BIP44 derivation	number	True
publicKey	Public key of the from address	string	True

signMessage

Description

Perform ethereum personal_sign.

async signMessage(signMsgData: types.signMsg): Promise<string>

signMsg Arguments

Arg	Description	Type	Required
transport	Object to communicate with CoolWallet device	Transport	True
appPrivateKey	Private key for the connected application	string	True
appId	ID for the connected application	string	True
message	Message to sign	string	True
addressIndex	The from address index in BIP44 derivation	number	True

signTypedData

Description

Perform ethereum sign_typed_data.

async signTypedData(typedData: types.signTyped): Promise<string>

signTyped Arguments

Arg	Description	Type	Required
transport	Object to communicate with CoolWallet device	Transport	True
appPrivateKey	Private key for the connected application	string	True
appId	ID for the connected application	string	True
typedData	Typed structured data to be signed	any	True
addressIndex	The from address index in BIP44 derivation	number	True

Add New Chain

• mkdir src/chain/new
• Create index.ts and token.ts in src/chain/new
• token.ts:

export const TOKENS = {};

• index.ts:

import { TOKENS } from './token';
import { ChainProps } from '../types';

class NewChain extends ChainProps {
  id = NewChainId as number;
  symbol = 'NewChainSymbol';
  signature = '';
  tokens = TOKENS;
}

export default new NewChain();

• export NewChain from src/chain/index.ts

export { default as NEW } from './new';

• Add NewChain to tools/chain to generate encoded data which should be signed.

console.log('New Chain Information', CHAIN.NEW.toHexChainInfo());