NEAR Paper Wallet

Based on proposal in NEAR forums.

Paper Wallets are great way to onboard new users. They are also a great way to save funds off-chain (cold storage).

Technically it is not a difficult task - just two QR codes with public and private key. However some sweeping functionality need to be added to the real wallets.

In case of NEAR wallet account name also need to be provided. Something as paper-xxx.somebody.testnet, where somebody.testnet is the parent account, which will create and initially fund the wallet.

Used libraries and services

• near-api-js - A JavaScript/TypeScript library for development of DApps on the NEAR platform
• bn.js - BigNum in pure javascript
• js-sha256 - A simple SHA-256 / SHA-224 hash function for JavaScript supports UTF-8 encoding

Installation

git clone https://github.com/zh/near-paper
cd near-paper
npm install

• [TODO] for browser

<script src="https://unpkg.com/near-paper"></script>

Usage

All provided examples are requiring parent account name (sender - the account, which will create the wallet) and network (testnet or mainnet). The easiest place to set them is in the .env file in the same directory. File format:

NETWORK=testnet
SENDER=somebody.testnet

Also there is need from access keys (created for example with near login). For more information see also access keys NEAR documentation.

The example/utils.js file provides example for using local file key store.

TODO: browser local storage as key store example.

const NearPaperWallet = require('near-paper');
const AMOUNT = '1.5'
const RECEIVER = 'somebody.testnet'

async function paperWalletTests(sender, amount) {
  try {
    const keyStore = ... // provide key store here
    const wallet = new NearPaperWallet(process.env.SENDER, keyStore);

    // create wallet with 1.5 NEAR initial amount
    await wallet.create(AMOUNT);
    wallet.save();
    console.log(JSON.stringify(wallet, null, 2));

    // sweep all funds
    // wallet.load('--put-correct-name-here--')
    const result = await wallet.sweep(RECEIVER);
    console.log('Transaction Results: ', result.transaction);

    // delete the wallet
    await wallet.delete();

  } catch (error) {
    console.error('error in paperWalletTests: ', error);
  }
}

paperWalletTests();

You can see more usage examples in the examples directory.

Example session

Create wallet

$ node ./examples/create-wallet.js -h
Options:
  -a, --amount   Amount of NEAR to put in the wallet                    [number]

Create NEAR paper wallet with 2 NEAR initial amount

$ node ./examples/create-wallet.js -a 2
{
  "sender": "devops.testnet",
  "networkId": "testnet",
  "accountId": "paper-1621445075752.devops.testnet",
  "privateKey": "41AsYv...",
  "onBlockchain": true,
  "keyStore": {
    "keyDir": "/Users/stoyan/.near-credentials"
  }
}
wallet paper-1621445075752.devops.testnet saved successfully.

This will also create JSON file in the root directory with name paper-1621445075752.devops.testnet.json and content:

{
  "accountId": "paper-1621445075752.devops.testnet",
  "privateKey": "41AsYv...",
  "onBlockchain": true
}

The example will also show a QR code with link like https://wallet.testnet.near.org/send-money/{paper_wallet_name} on the console. You can fund the wallet by scanning the QR code. It will redirect you to the web wallet site as a usual 'Receive' QR code.

Sweep all funds from the paper wallet

receiver is the account name to receive the funds.

$ node ./examples/sweep-wallet.js -h
Options:
  -r, --receiver  Account to get sweeped tokens                         [string]
  -w, --wallet    Paper wallet name                                     [string]

$ node ./examples/sweep-wallet.js -r devops.testnet -w paper-1621445075752.devops.testnet
balance: "1981800000000000000000000"
Transaction Results:  {
  signer_id: 'paper-1621445075752.devops.testnet',
  public_key: 'ed25519:F6ENP...',
  nonce: 48275784000001,
  receiver_id: 'devops.testnet',
  actions: [ { Transfer: [Object] } ],
  signature: 'ed25519:3qEP...',
  hash: 'a8Vt43dU78HjPKbuF6F6XAQ7JBNS5KMNDc5CE98f3ya'
}
https://explorer.testnet.near.org/transactions/a8Vt43dU78HjPKbuF6F6XAQ7JBNS5KMNDc5CE98f3ya

TODO: This need to be added to some real wallet. Not sure also what to contain the QR code: maybe something like {paper_wallet_name}:{private_key}: read the QR code; parse it to get name and key and sweep the funds

Delete the paper wallet

Paper wallets can be reused as many times as needed or can be deleted.

$ node ./examples/delete-wallet.js -h
Options:
  -w, --wallet   Paper wallet name                                      [string]

$ node ./examples/delete-wallet.js -w paper-1621445075752

This will modify the wallet JSON file with "onBlockchain": false.

TODO

• More flexible credentials handling
• Create JS npm package
• Create QR codes in addition to JSON file
• Sweep module for some wallet