Raw Transaction Construction

The blxr_tx endpoint is expecting raw transaction bytes. Constructing the transaction is typically done using a library like web3 or ethers. The below examples demonstrate constructing a raw transaction and submitting it to blxr_tx .

Examples - Create a Simple Transfer raw transaction and submit it to blxr_tx api

Node.js

const WebSocket = require('ws')
const EthereumTx = require('ethereumjs-tx').Transaction
// Needed for BSC
// const Common = require('ethereumjs-common').default
const Web3 = require('web3')

const web3 = new Web3('PROVIDER_URL')

const account = 'YOUR_ADDRESS'

const privateKey = Buffer.from(
  'YOUR_PRIVATE_KEY',
  'hex',
)

// const BSC = Common.forCustomChain(
//   'mainnet',
//   {
//       name: 'Binance Smart Chain Mainnet',
//       networkId: 56,
//       chainId: 56,
//       url: 'https://bsc-dataseed.binance.org/'
//   },
//   'istanbul',
// )

const main = async () => {
  const tx = new EthereumTx({
      to: 'TO_ADDRESS',
      nonce: nonce,
      // Pass in decimal number for fields below
      gasPrice: web3.utils.toHex(),
      gas: web3.utils.toHex(),
      value: web3.utils.toHex(),
      chainId: 1
      // If using BSC
      // chainId: 56
    } //, { common: BSC } 
  )
  tx.sign(privateKey)

  const serializedTx = tx.serialize()
  const rawTx = serializedTx.toString('hex')
  
  const ws = new WebSocket(
    "ws://127.0.0.1:28333/ws", 
    {
      headers: { 
        "Authorization" : <YOUR-AUTHORIZATION-HEADER>
      },
      rejectUnauthorized: false,
    }
  );

  function proceed() {
    ws.send(`{"jsonrpc": "2.0", "id": 1, "method": "blxr_tx", "params": {"transaction": "${rawTx}"}}`)
  }

  function handle(response) {
    console.log(response.toString()) // Or process it generally
  }
  ws.on('open', proceed)
  ws.on('message', handle)
}

Python

Go

Examples - Create a Token Swap raw transaction and submit it to blxr_tx api

Node.js

const fs = require('fs')
const WebSocket = require('ws')
const EthereumTx = require('ethereumjs-tx').Transaction
const Common = require('ethereumjs-common').default
const Web3 = require('web3')

const web3 = new Web3('PROVIDER_URL')

const account = 'YOUR_ADDRESS'

const privateKey = Buffer.from(
  'PRIVATE_KEY',
  'hex',
)

// Network you would like to connect to, in this case BSC Mainnet
const BSC_FORK = Common.forCustomChain(
  'mainnet',
  {
      name: 'Binance Smart Chain Mainnet',
      networkId: 56,
      chainId: 56,
      url: 'https://bsc-dataseed.binance.org/'
  },
  'istanbul',
)


const main = async () => {
  const bnb = 'WBNB_TOKEN_ADDRESS'
  const token = 'TOKEN_ADDRESS_TO_SWAP_FOR'

  const pair = [bnb, token]

  // Amount of BNB to swap
  const tokenAmountIn = web3.utils.toHex()
  // Desired amount of token returned
  const amountOutMin = web3.utils.toHex()

  const pancakeSwapRouterAddress = 'PANCAKESWAP_ROUTER_ADDRESS'

  // Export Pancakeswap ABI to json file in same directory
  const abi = JSON.parse(fs.readFileSync('pancake-router-abi.json', 'utf-8'));
  const contract = new web3.eth.Contract(abi, pancakeSwapRouterAddress, {from: account})
    
  const data = contract.methods.swapExactETHForTokens(
    amountOutMin,
    pair,
    account,
    Date.now() + 1000 * 60 * 10,
    )

    const tx = new EthereumTx({
        to: pancakeSwapRouterAddress,
        nonce: nonce,
        // Desired gas usage in decimal format
        gasPrice: web3.utils.toHex(),
        gas: web3.utils.toHex(),
        value: tokenAmountIn,
        data: data.encodeABI(),
        chainId: 56
      }, {common: BSC_FORK}
    )

  tx.sign(privateKey)

  const serializedTx = tx.serialize()
  const rawTx = serializedTx.toString('hex')
    
  const ws = new WebSocket(
    "ws://127.0.0.1:28333/ws", 
    {
      headers: { 
        "Authorization" : <YOUR-AUTHORIZATION-HEADER>
      },
      rejectUnauthorized: false,
    }
  );

  function proceed() {
    ws.send(`{"jsonrpc": "2.0", "id": 1, "method": "blxr_tx", "params": {"transaction": "${rawTx}", "blockchain_network": "BSC-Mainnet"}}`)
  }

  function handle(response) {
    console.log(response.toString()) // Or process it generally
  }
  ws.on('open', proceed)
  ws.on('message', handle)
}

Python

Go