Posting Transactions using arweave-js
Arweave native transactions can be posted directly to a node or gateway using the arweave-js package.
Arweave scales though the use of transaction bundles. These bundles make it possible for each block to contain a nearly unlimited number of transactions. Without the use of bundles, Arweave blocks are limited 1000 transactions per block (with new blocks produced every ~2 minutes). If your use case exceeds this capacity you may experience dropped transactions. Under these circumstances please consider using irys.xyz or similar services to bundle your transactions.
Installing the arweave-js Package
To install arweave-js run
npm install --save arweave
yarn add arweave
When working with NodeJS a minimum version of NodeJS 18 or higher is required.
Initializing arweave-js
Direct Layer 1 transactions are posted using the arweave-js library.
import Arweave from 'arweave';
import fs from "fs";
// load the JWK wallet key file from disk
let key = JSON.parse(fs.readFileSync("walletFile.txt").toString());
// initialize an arweave instance
const arweave = Arweave.init({});
Posting a wallet-to-wallet Transaction
A basic transaction to move AR tokens from one wallet address to another.
// create a wallet-to-wallet transaction sending 10.5AR to the target address
let transaction = await arweave.createTransaction({
target: '1seRanklLU_1VTGkEk7P0xAwMJfA7owA1JHW5KyZKlY',
quantity: arweave.ar.arToWinston('10.5')
}, key);
// you must sign the transaction with your key before posting
await arweave.transactions.sign(transaction, key);
// post the transaction
const response = await arweave.transactions.post(transaction);
Posting a Data Transaction
This example illustrates how load a file from disk and create a transaction to store its data on the network. You can find the current price the network is charging at https://ar-fees.arweave.dev
// load the data from disk
const imageData = fs.readFileSync(`iamges/myImage.png`);
// create a data transaction
let transaction = await arweave.createTransaction({
data: imageData
}, key);
// add a custom tag that tells the gateway how to serve this data to a browser
transaction.addTag('Content-Type', 'image/png');
// you must sign the transaction with your key before posting
await arweave.transactions.sign(transaction, key);
// create an uploader that will seed your data to the network
let uploader = await arweave.transactions.getUploader(transaction);
// run the uploader until it completes the upload.
while (!uploader.isComplete) {
await uploader.uploadChunk();
}
Resources
For an overview of all the ways you can post transactions, see the Posting Transactions section of the cookbook.
For a more detailed description of all
arweave-js's features see the documentation on github