Transactions

This document explains how to influence the blockchain's state by broadcasting transactions.

Transactions include:

• A list of messages.
• An optional memo.
• A fee.
• A signature from a key.

The messages included in a transaction contain the information that will be routed to a proper message handler in the node, which in turn parses the inputs and determines the next state of the blockchain.

Create transactions

Create a wallet

You will first want to create a wallet that you can use to sign transactions.

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import { MnemonicKey, LCDClient } from '@terra-money/feather.js';

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const mk = new MnemonicKey();

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const terra = new LCDClient({

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URL: 'https://pisco-lcd.terra.dev',

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chainID: 'pisco-1',

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});

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const wallet = terra.wallet(mk);

Create messages

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import { MsgSend } from '@terra-money/feather.js';

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const send = new MsgSend(

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wallet.key.accAddress('terra'),

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'<random-terra-address>',

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{

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uluna: 1000,

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},

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);

Create and Sign Transaction

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const tx = await wallet.createAndSignTx({

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msgs: [send],

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memo: 'Hello',

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chainID: 'pisco-1',

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});

Broadcast transaction

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const txResult = await terra.tx.broadcast(tx, 'pisco-1');

The default broadcast mode is block, which waits until the transaction has been included in a block. This will give you the most information about the transaction, including events and errors while processing.

You can also use sync or async broadcast modes.

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// const syncTxResult = await terra.tx.broadcastSync(tx, 'pisco-1');

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// const asyncTxResult = await terra.tx.broadcastAsync(tx, 'pisco-1');

Check events

If you broadcasted the transaction with block, you can get the events emitted by your transaction.

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import { isTxError } from '@terra-money/feather.js';

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const txResult = terra.tx.broadcast(tx, 'pisco-1');

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if (isTxError(txResult)) {

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throw new Error(

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`encountered an error while running the transaction: ${txResult.code} ${txResult.codespace}`,

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);

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}

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// check for events from the first message

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txResult.logs[0].eventsByType.store_code;