Hello, Viewing Keys

Read the code for this tutorial here

Overview

In this tutorial we are going to learn how to build an application that allows you to connect to Keplr, once connected you can create your viewing key and finally get your account balance.

Requirements

In order to go through this tutorial you'll need to have a React app created. You can find how to do it here. Also, install your dependencies and install Griptape.

# With npm
npm install && npm install @stakeordie/griptape.js

# With yarn
yarn && yarn add @stakeordie/griptape.js

Getting started

This tutorial consist of these steps:

1. Grip you application

2. Bootstrap the application

3. Create a contract definition

4. Build the app

Grip your application

Go to the src/index.js and import gripApp and getKeplrAccountProvider from @stakeordie/griptape.js package.

src/index.js

import {
  gripApp,
  getKeplrAccountProvider
} from "@stakeordie/griptape.js";

You can check how to grip your app here

Bootstrap the application

Open up src/App.js and add a button to bootstrap the application.

src/App.js

<>
    <h1>Hello, Viewing Keys!</h1>
    <p>Is connected? { isConnected ? "Yes": "No" }</p>
    <button
      onClick={() => bootstrap()}
      disabled={isConnected}>Bootstrap
    </button>
</>

You can check how to boostrap your app here

Create a contract definition

In order to interact with a contract, you first need to create its definition. First we need to import createContract and snip20Def APIs from @stakeordie/griptape.jsto our file src/contracts/sscrt.js Once that is done, we create the definition sscrt to which we are going to assign an id that can be the name you want, we are also going to assign an address of instantiated contract on the blockchain.

Finally, Griptape has SNIP-20 compliant contract definitions, so you don't need to write it yourself.

src/contracts/sscrt.js

import {
  createContractClient,
  snip20Def
} from '@stakeordie/griptape.js';

export const sscrt = createContractClient({
  id: 'sscrt',
  at: 'secret18vd8fpwxzck93qlwghaj6arh4p7c5n8978vsyg',
  definition: snip20Def
});

Learn more about contract definitions here

Build the application

To start building our application, we need to import bootstrap, viewingKeyManager, onAccountAvailableand coinConvert APIs from @stakeordie/griptape.js and also import the contract definition we just made sscrt from "./contracts/sscrt".

src/App.js

import {
  bootstrap,
  viewingKeyManager,
  onAccountAvailable,
  coinConvert
} from '@stakeordie/griptape.js';
import { sscrt } from './contracts/sscrt';

We now see that we are using the onAccountAvailable event which you can read more about here. Inside our event we query the viewingKeyManager with our address contract sscrt.at, after that if a key already exists we assign it to state setViewingKey.

src/App.js

    const removeOnAccountAvailable = onAccountAvailable(() => {
      const key = viewingKeyManager.get(sscrt.at);
      if (key) {
        setViewingKey(key);
      }
    })

To create a viewing key, we're going to make an asynchronous request to sscrt.createViewingKey(), if this doesn't return a response, the function ends. If it is the case and if it returns a response then, we parse the result. Now we send our contract sscrt and our key. We also need to check if a viewing key already exists so we can add it by viewingKeyManager.add() or replace it by viewingKeyManager.set()with the new key.

src/App.js

const createViewingKey = async () => {

    setLoading(true);
    try {
      const result = await sscrt.createViewingKey();

      if (result.isEmpty()) return;

      const { create_viewing_key: { key } } = result.parse();
      viewingKeyManager.add(sscrt, key);
      setViewingKey(key);
      const currentKey = viewingKeyManager.get(sscrt.at);
     
      if (currentKey) {
        viewingKeyManager.set(sscrt, key);
      } else {
        viewingKeyManager.add(sscrt, key);
      }
    } catch (e) {
      // ignore for now
    } finally {
      setLoading(false);
    }

  }

After having our viewing key, we want to see our balance. For that reason, we create the function getBalance, within the function, we can see that we make an asynchronous request to obtain the value of our viewing key.

If we do not have a viewing key the function ends, but if this is the case, where we have a viewing key, then we went to consult our amount In sscrt.getBalance(), then we convert our amount with the function coinConvert where ... and finally we assign the value of balance the state setCoins.

src/App.js

const getBalance = async () => {
    const key = viewingKeyManager.get(sscrt.at);
    if (!key) return;
    const amount = await sscrt.getBalance();
    const balance = coinConvert(amount.balance.amount, 6, 'human');
    setCoins(balance);
  }

And this is what our full application should look like, adding a bit of JSX.

src/App.js

import React, { useState, useEffect } from "react";
import {
  bootstrap,
  viewingKeyManager,
  onAccountAvailable,
  coinConvert
} from '@stakeordie/griptape.js';
import { sscrt } from './contracts/sscrt';

function App() {

  var [loading, setLoading] = useState(false);
  var [coins, setCoins] = useState('');
  var [viewingKey, setViewingKey] = useState('');
  var [isConnected, setIsConnected] = useState(false);

  useEffect(() => {
    const removeOnAccountAvailable = onAccountAvailable(() => {
      setIsConnected(true);
      const key = viewingKeyManager.get(sscrt.at);
      if (key) {
        setViewingKey(key);
      }
    })
    return () => {
      removeOnAccountAvailable();
    }
  }, []);

  const createViewingKey = async () => {

    setLoading(true);
    try {
      const result = await sscrt.createViewingKey();

      if (result.isEmpty()) return;

      const { create_viewing_key: { key } } = result.parse();
      viewingKeyManager.add(sscrt, key);
      setViewingKey(key);
      const currentKey = viewingKeyManager.get(sscrt.at);

      if (currentKey) {
        viewingKeyManager.set(sscrt, key);
      } else {
        viewingKeyManager.add(sscrt, key);
      }
    } catch (e) {
      // ignore for now
    } finally {
      setLoading(false);
    }

  }

  const getBalance = async () => {
    const key = viewingKeyManager.get(sscrt.at);
    if (!key) return;
    const amount = await sscrt.getBalance();
    const balance = coinConvert(amount.balance.amount, 6, 'human');
    setCoins(balance);
  }

  return (
    <>
      <h1>Hello, Viewing Keys!</h1>
      <p>Is connected? {isConnected ? "Yes" : "No"}</p>
      <button
        onClick={() => { bootstrap(); }}
        disabled={isConnected}>Bootstrap
      </button>
      <p>Your viewing key is: {viewingKey}</p>
      <p>Your balance is: {coins}</p>
      <button disabled={!isConnected} onClick={() => { createViewingKey(); }}>{loading ? 'Loading...' : 'Create Viewing Key'}</button>
      <button disabled={!viewingKey} onClick={() => { getBalance(); }}>Get balance</button>
    </>
  );
}

export default App;