Submit bulk Tx @ Matic DA Blockchain

index.js

const { ApiPromise, WsProvider, Keyring } = require('@polkadot/api')
const { Buffer } = require('buffer')
const { createWriteStream } = require('fs')

const BATCH = process.env.BATCH || 100 // these many tx(s) to be attempted to be submitted
const PAYLOAD = process.env.PAYLOAD || 512 // in terms of bytes
const WSURL = process.env.WSURL || 'ws://localhost:9944'

// To be initialized, after `setUp` is called
let handle
const fd = createWriteStream('./tx.log', { flags: 'a' })

const keyring = new Keyring({ type: 'sr25519' })

// Initializing Polkadot API for using it with Matic DA Blockchain
const setUp = async _ => {

    const provider = new WsProvider(WSURL)

    const api = await ApiPromise.create({
        provider, types: {
            ExtrinsicsRoot: {
                hash: 'Hash',
                commitment: 'Vec<u8>'
            },
            Header: {
                parentHash: 'Hash',
                number: 'Compact<BlockNumber>',
                stateRoot: 'Hash',
                extrinsicsRoot: 'ExtrinsicsRoot',
                digest: 'Digest'
            }
        }
    })

    return api

}

// Generates random byte array of specified size
const generateData = size => {

    let buffer = Buffer.alloc(size)

    for (let i = 0; i < size; i++) {
        buffer.writeUInt8(Math.floor(Math.random() * 256), i)
    }

    return buffer.toString('hex')

}

// Attempts to calculate nonce of account
const getNonce = async account => {

    try {
        const nonce = await handle.rpc.system.accountNextIndex(account.address)
        return nonce
    } catch (e) {
        console.error(e.toString())
        return 0
    }

}

// Sends a tx & tracks its life cycle until it becomes finalized
const sendTx = (sender, nonce, size) => new Promise(async (res, rej) => {

    try {

        const unsub = await handle.tx.templateModule
            .submitData(generateData(size))
            .signAndSend(sender, { nonce }, async result => {

                if (result.status.isReady) {

                    console.log(`Tx with nonce ${nonce} [ READY ]`)
                    return

                }

                // Wait until tx is included in block
                if (result.status.isInBlock) {

                    console.log(`Tx with nonce ${nonce} in ${result.status.asInBlock} [ INCLUDED ]`)

                    unsub()
                    res(result.status.asInBlock)

                }

            })

    } catch (e) {
        rej(e)
    }

})

// Sends `BATCH` many tx(s), where each attempts to submit `PAYLOAD` bytes
// data
const sendTxs = (sender, options) => new Promise(async (res, rej) => {

    let batch = BATCH
    let payload = PAYLOAD

    if (options !== undefined && options !== null) {

        batch = options.BATCH || BATCH
        payload = options.PAYLOAD || PAYLOAD

    }

    let promises = []
    let nonce = BigInt(await getNonce(sender))

    for (let i = 0; i < batch; i++) {

        promises.push(sendTx(sender, nonce, payload))
        nonce += 1n // keep incrementing nonce before sending next tx

    }

    // Creating an easy to digest stat of how many tx(s) got included
    // in each block
    //
    // @note We attempted to send `BATCH` tx(s) in a single go
    // and may be not all of them got included in same block
    await Promise.all(promises).then(v => {

        res(v.reduce((acc, cur) => {

            if (cur in acc) {
                acc[cur]++
            } else {
                acc[cur] = 1
            }

            return acc

        }, {}))

    }).catch(rej)

})

// Main entry script, for submitting bulk tx(s)
const main = async _ => {

    // Initialising global variable, so all tx sending can use this same API instance
    handle = await setUp()

    const alice = keyring.addFromUri('//Alice', { name: 'Alice default' })
    const bob = keyring.addFromUri('//Bob', { name: 'Bob default' })

    for (let batch = 1; batch < 10000; batch++) {

        for (let payload = 1; payload < 2048; payload++) {

            const options = { BATCH: batch, PAYLOAD: payload }

            await Promise.all([sendTxs(alice, options), sendTxs(bob, options)]).then(v => {

                const stat = {
                    ...options,
                    stat: v.reduce((acc, cur) => {

                        Object.keys(cur).forEach(v => {
                            if (v in acc) {
                                acc[v] += cur[v]
                            } else {
                                acc[v] = cur[v]
                            }
                        })

                        return acc

                    }, {}),
                    ...{ time: new Date().toUTCString() }
                }

                console.log(`✅ Tx(s) finalized : 👇`)
                console.log(stat)

                fd.write(`${JSON.stringify(stat, null, 2)}\n`)


            }).catch(e => { console.error(e.toString()); fd.close(); process.exit(1) })

        }

    }

}

main().catch((e) => { console.error(e.toString()); process.exit(1); })

package.json

{
  "name": "matic-da-bulk-tx",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "node index.js",
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "Anjan Roy<[email protected]>",
  "license": "ISC",
  "dependencies": {
    "@polkadot/api": "^4.0.3"
  }
}

This script is supposed to be used for submitting bulk tx in Matic's DA blockchain.

Usage

• Download GIST & install dependencies

npm i

• Get a DA node up & running, with websocket interface exposed, by default ws://localhost:9944 to be used
• Run index.js with

npm run start

---

It'll attempt to generate random byte array payload of size 512 bytes ( by default ) & submit 1024 ( by default ) tx(s) in a single go. After all those 1024 tx(s) get confirmed, it'll start next iteration.

If you want to change how many tx(s) to be sent/ how much data to be submitted in each tx, consider updating BATCH/ PAYLOAD, respectively.

Updated script attempts to run for multiple possible combinations of BATCH_SIZE & PAYLOAD_SIZE & keeps result in tx.log file in JSON serialised form in append only mode.