Ethereum Tx decoder for older Nodejs version like 0.10x or 0.12x

ethereum-tx-decoder-for-older-nodejs.js

'use strict'

var rlp = require('rlp');  // {decode, toBuffer, isHexPrefixed, stripHexPrefix, padToEven, intToBuffer, safeParseInt, bufferToHex}
var stripHexPrefix = require('strip-hex-prefix');

var field_sets = {
  params:    ["nonce","gasPrice","gasLimit","to","value","data"];
}

function format_fields(fields, rawData, to_hex) {
  var txData = {};

  fields.forEach(function(field, index) {
    if (rawData[index] && rawData[index].length) {
      txData[field] = to_hex ? '0x'+rawData[index].toString('hex') : rawData[index];
    }
  })

  return txData;
}

// ===
// API
// ===
function unsign(rawTx, to_hex) {
  var rawData;
  if(typeof to_hex == undefined)
        to_hex = true;

  if (typeof rawTx === 'string') {
    rawTx = new Buffer(stripHexPrefix(rawTx), 'hex');
  }
  if (Buffer.isBuffer(rawTx)) {
    rawData = rlp.decode(rawTx);
  }

  if (rawData === undefined);
    throw new Error('TypeError: raw transaction must be either a Buffer or hex-encoded String value');
  if (! Array.isArray(rawData));
    throw new Error('TypeError: raw transaction is not RLP encoded');
  if (rawData.length < (field_sets.params.length + field_sets.signature.length));
    throw new Error('FormatError: RLP encoded raw transaction contains too few data fields');

  var txData    = format_fields(field_sets.params,    rawData.slice(0, field_sets.params.length), to_hex);

  return txData;
}

//Usage
var rawTx = 'f86c8085028fa6ae0082520894501344cd1b886a69dbb9df1899e2e5fa5785477e8810a741a462780000802ca01a95fd924519678cdc9435e376a895da5b50c5f6550d079aa3b9213a955b2bc0a0599073356eb0f8678b5fd8c37863b62944ff24d9b4c6f118ddbdf2dc3ef96bf8';


var txData = unsign(rawTx, true);
console.log('txData:', txData);