Submitting Transactions

Build, sign, and submit peaq transactions with ethers.js. Configure a provider and wallet, send funds or contract calls, and verify transaction receipts.

A transaction is required every time you write data to peaq: transferring funds, calling a smart contract, or deploying one. Your code builds the transaction and signs it. This guide does that with ethers.js.

Prerequisites

• Node.js installed, and npm install ethers dotenv in your project.
• A funded account and its private key in an environment variable. Never put a private key or mnemonic in your source code.
• The RPC URL of the network you are using. See Connecting to peaq.
• The transaction details: recipient address, value, and call data if you are calling a contract.

Instructions

1. Import ethers.js

In your JavaScript file, import ethers.js:

import { ethers } from 'ethers';

2. Set up a provider

Connect to the network:

const provider = new ethers.JsonRpcProvider(process.env.RPC_URL);

3. Configure a signer

Create a wallet instance to sign transactions:

const privateKey = process.env.PRIVATE_KEY;
const wallet = new ethers.Wallet(privateKey, provider);

4. Define the transaction

Set up the transaction details:

const tx = {
  to: "0xRecipientAddressHere", // replace with the recipient's address
  value: ethers.parseEther("0.1"), // amount of PEAQ to send
  gasLimit: 21000, // gas limit for a simple transfer
};

Leave maxFeePerGas and maxPriorityFeePerGas out of the object and ethers reads the current fees from the node when it sends the transaction. To call a smart contract, add data.

5. Sign and submit the transaction

async function sendTransaction() {
  try {
    const txResponse = await wallet.sendTransaction(tx);
    console.log("Transaction submitted:", txResponse.hash);
    const receipt = await txResponse.wait();
    console.log("Transaction mined:", receipt);
  } catch (error) {
    console.error("Error submitting transaction:", error);
  }
}

sendTransaction();

6. Verify the transaction

Look up txResponse.hash on Subscan, or check the status in your code with provider.getTransactionReceipt.

Contracts

For a contract call, build the contract instance from its ABI and address and connect it to the wallet:

const contract = new ethers.Contract(contractAddress, contractABI, wallet);

To estimate the gas a contract call needs, use contract.methodName.estimateGas(...args).

Putting it all Together

A complete script that ties the steps together, including environment variable handling.

JavaScript

import 'dotenv/config';
import { ethers } from 'ethers';

async function main() {
  try {
    // Step 1: Set up the provider
    const rpcUrl = process.env.RPC_URL;
    if (!rpcUrl) throw new Error("RPC_URL is not defined in .env");
    const provider = new ethers.JsonRpcProvider(rpcUrl);

    // Step 2: Configure the wallet (signer)
    const privateKey = process.env.PRIVATE_KEY;
    if (!privateKey) throw new Error("PRIVATE_KEY is not defined in .env");
    const wallet = new ethers.Wallet(privateKey, provider);

    console.log(`Connected wallet: ${wallet.address}`);

    // Step 3: Define the transaction
    const tx = {
      to: "0xRecipientAddressHere", // replace with the recipient's address
      value: ethers.parseEther("0.1"), // amount of PEAQ to send
      gasLimit: 21000, // gas limit for a simple transfer
    };

    console.log("Prepared transaction:", tx);

    // Step 4: Sign and send the transaction
    const txResponse = await wallet.sendTransaction(tx);
    console.log(`Transaction submitted: ${txResponse.hash}`);

    // Step 5: Wait for the transaction to be mined
    const receipt = await txResponse.wait();
    console.log(`Transaction mined in block ${receipt.blockNumber}`);
  } catch (error) {
    console.error("Error occurred:", error.message);
  }
}

main();

Running the script

1. Add "type": "module" to your package.json so Node treats the file as an ES module.
2. Create a .env file in the root of your project:

RPC_URL=https://quicknode1.peaq.xyz
PRIVATE_KEY=your-private-key

3. Replace 0xRecipientAddressHere with the recipient’s address and adjust value.
4. Run it:

node script.js