Terra 2.0

feather.js

feather.js is a fork of terra.js with interchain capabilities. It can be used to interact with Cosmos blockchains like Terra within JavaScript runtimes, such as Node.js and the browser. To learn more about feather.js and installing the package, look here.

Setup

Getting started takes a few steps:

Importing feather.js and relevant classes
An LCDClient to connect to the Terra 2 blockchain
A MnemonicKey to sign and broadcast transactions
A wallet (inputs our MnemonicKey into our LCDClient)

import { LCDClient, MnemonicKey, MsgExecuteContract, Coins, Fee } from '@terra-money/feather.js';
const lcd = new LCDClient({
  // key must be the chainID
  'pisco-1': {
    lcd: 'https://pisco-lcd.terra.dev', // testnet lcd
    chainID: 'pisco-1', // testnet chain-id
    gasAdjustment: 1.75,
    gasPrices: { uluna: 0.015 },
    prefix: 'terra', // bech32 prefix
  },
});
const mk = new MnemonicKey({
  mnemonic: '',
});
const wallet = lcd.wallet(mk);

Executing Messages

To execute a contract message, we create a new MsgExecuteContract object variable containing our wallet, the contract we are sending our message to, our message itself, and any Coins to send along with our transaction.

This object then gets passed into a tx variable which creates and signs the transaction. A custom fee variable can also be passed in.

Finally, our transaction gets broadcasted and the result is printed in the console.

const contract_address = '<INSERT_CONTRACT_ADDRESS>'; // A terra address on pisco-1
const execute = new MsgExecuteContract(
  wallet.key.accAddress('terra'),
  contract_address,
  {
    "swap": {
      "offer_asset": {
        "info": {
          "native_token": {
            "denom": "uluna"
          }
        },
        "amount": "100000"
      }
    }
  }, // Example execute message  
  new Coins({ uluna: '100000' }) // Coins to send with transaction
);
// Broadcast transaction
const fee = new Fee(500000, { uluna: 200000 }); // 
const tx = await wallet.createAndSignTx({
  msgs: [execute],
  fee,
  chainID: 'pisco-1',
});
const result = await lcd.tx.broadcast(tx, 'pisco-1');
console.log(result);

Querying Data

To query data from a contract, you just need to make an async call to the LCDClient containing the contract to query and the query itself. Note that you don't need a MnemonicKey or wallet to execute queries.

const contract_address = '<INSERT_CONTRACT_ADDRESS>'; // A terra address on pisco-1
const query = await lcd.wasm.contractQuery(
  contract_address, 
  {
    "config": {} // Example query
  }
).then(result => { console.log(result) }); // Print result

Terra 2.0

feather.js​

Setup​

Executing Messages​

Querying Data​

feather.js

Setup

Executing Messages

Querying Data