Mirror.js

This section provides a brief guide on how to get set up with Mirror.js. For more information, be sure to check out source code and documentation on GitHub.

Mirror.js is a client SDK for building applications that can interact with Mirror Protocol from within JavaScript runtimes, such as web browsers, server backends, and on mobile through React Native.

You can find a reference of the Mirror.js API here.

Getting Mirror.js

Mirror.js is available as a package on NPM and is intended to be used alongside Terra.js.

Add both:

• @terra-money/terra.js

• @mirror-protocol/mirror.js

To your JavaScript project's package.json as dependencies using your preferred package manager:

$ npm install -S @terra-money/terra.js @mirror-protocol/mirror.js

Usage

Mirror object

Mirror.js provides facilities for 2 main use cases:

• query: runs smart contract queries through LCD

• execute: creates proper MsgExecuteContract objects to be used in transactions

Both of these functions are accessible through the Mirror object.

To create the Mirror object:

import { LCDClient } from '@terra-money/terra.js';
import { Mirror } from '@mirror-protocol/mirror.js';

// default -- uses Columbus-4 core contract addresses
const mirror = new Mirror();

// optional -- specify contract addresses and assets
const mirror = new Mirror({
  lcd: new LCDClient(...),
  key: new MnemonicKey(), // or other Terra.js-compliant key
  collector: 'terra1...',
  community: 'terra1...',
  factory: 'terra1...',
  gov: 'terra1...',
  mint: 'terra1...',
  oracle: 'terra1...',
  staking: 'terra1...',
  mirrorToken: 'terra1...',
  terraswapFactory: 'terra1...',
  assets: {
    MIR: {
      name: 'Mirror';
      symbol: 'MIR';
      token: 'terra1...'; // Terraswap token contract
      lpToken: 'terra1...'; // Terraswap LP token contract
      pair: 'terra1...'; // Terraswap pair contract against UST
    },
    mAAPL: {
      name: 'Mirrored Apple, Inc. stock';
      symbol: 'mAAPL';
      token: 'terra1...'; // Terraswap token contract
      lpToken: 'terra1...'; // Terraswap LP token contract
      pair: 'terra1...'; // Terraswap pair contract against UST
    },
    ...
  }
});

Query

The Mirror object contains contract queries for all of the Mirror core contracts, which it will run against the provided LCDClient.

async function main() {
  const result = await mirror.factory.getConfig();
}

main().catch(console.error);

Each contract has various query operations, which you can discover in the reference API documentation.

Executing

The Mirror object contains functions for generating proper MsgExecuteContract messages to be included in a transaction and broadcasted.

const wallet = mirror.lcd.wallet(mirror.key);

async function sendMIR() {
  const tx = await wallet.createAndSignTx({
    msgs: [mirror.mirrorToken.transfer('terra1...', 1_000_000)],
    fee: new StdFee(200_000, { uluna: 20_000_000 })
  });
  return await mirror.lcd.tx.broadcast(tx);
}

async function stakeLPTokens() {
  const { mAAPL } = mirror.assets;
  const tx = await wallet.createAndSignTx({
    msgs: [
      mirror.staking.bond(
        mAAPL.pair.contractAddress,
        500_000_000,
        mAAPL.lpToken
      )
    ],
    fee: new StdFee(200_000, { uluna: 20_000_000 })
  });
  return await mirror.lcd.tx.broadcast(tx);
}

async function main() {
  await sendMIR();
  await stakeLPTokens();
}

main().catch(console.error);