Sending your first transaction

Creating a transaction

Every action on blockchain can be considered as a transaction: sending native token, sending utility tokens, calling a smart contract, creating an NFT...

TL;DR

Sending a basic transaction can be done by following these steps:

1. Get your wallet's latest nonce

2. Estimate gas price

3. Estimate gas limit

4. Parse your payload to KardiaChain RPC protocol format

5. Sign your transaction

6. Send signed transaction to network

To get wallet's latest nonce, use account module

import KardiaClient from 'kardia-js-sdk';
const RPC_ENDPOINT = 'YOUR_RPC_ENDPOINT';

const kardiaClient = new KardiaClient({ endpoint: RPC_ENDPOINT });

// Get your wallet's latest nonce
const nonce = await kardiaClient.account.getNonce('YOUR_WALLET_ADDRESS');

const txPayload = {
  to: 'RECEIVER_WALLET_ADDRESS',
  gas: 50000,      // Gas limit
  nonce,
  gasPrice: 1000000000,     // Gas price
  value: 231095,    // Amount of KAI to send
};

In most cases, estimating gas price and gas limit is pretty complex. Luckily, this can be done using the SDK.

To get recommended gas price from oracle, use the getGasPrice method from KAIChain module.

import KardiaClient from 'kardia-js-sdk';
const RPC_ENDPOINT = 'YOUR_RPC_ENDPOINT';

const kardiaClient = new KardiaClient({ endpoint: RPC_ENDPOINT });

const kaiChainModule = kardiaClient.kaiChain;

const oracleGasPrice = await kaiChainModule.getGasPrice();

To estimate gas limit for your transaction, use estimateGas method from transaction module

const transactionModule = kardiaClient.transaction

const txPayload = {
  to: 'RECEIVER_WALLET_ADDRESS',
  from: 'YOUR_WALLET_ADDRESS',
  gasPrice: oracleGasPrice, // Gas price from above step
  value: 231095,    // Amount of KAI to send
};

const txData = '0x12'; // Transaction data, this will usually be used when you want to execute a smart contract call

const estimatedGas = await transactionModule.estimateGas(txPayload, txData);

After this, your transaction payload is complete. Next you need to parse your payload to match KardiaChain RPC protocol. This can be done using generateTransaction utility

txPayload.gas = estimatedGas // Gas from above step

// txPayload now should be
// {
//   to: 'RECEIVER_WALLET_ADDRESS',
//   from: 'YOUR_WALLET_ADDRESS',
//   gasPrice: oracleGasPrice, // Gas price from above step
//   value: 231095,    // Amount of KAI to send
//   gas: estimatedGas
// };

const parsedPayload = transactionModule.generateTransaction(txPayload);

Then you can sign your transaction and send to KardiaChain network

const signedTx = transactionModule.signTransaction(parsedPayload, 'YOUR_PRIVATE_KEY');

// Send transaction to network and get transaction hash immediately
const txHash = await transactionModule.sendRawTransaction(signedTx);

// txHash should be something like '0x0a2db5831c314363a97a79f416061a9daec5230f8b6306cd1c431b467c42f820'

At this moment, your transaction has been submitted but not mined into a new block. To ensure that, you can create a loop to check for transaction receipt

while (true) {
  try {
    const receipt = await transactionModule.getTransactionReceipt(txHash);
    if (receipt) {
      return receipt; // Now your transaction is mined into a new block
    } else {
      await sleep(1000); //
    }
  } catch (err) {
    // Handle error here
  }
}

All the above steps can be combined by using sendTransaction method in transaction module

const txPayload = {
  to: 'RECEIVER_WALLET_ADDRESS',
  from: 'YOUR_WALLET_ADDRESS',
  value: 231095,    // Amount of KAI to send
}

const txResult = await transactionModule.sendTransaction(
  txPayload,
  'YOUR_WALLET_PRIVATEKEY',
  true,    // Flag to indicate if you want to wait for the transaction to complete
  50000    // Time (in ms) you want to wait for transaction to complete, default will be 300000 (300s)
);