I am working on university project and this is the only and last point i need your help. I want to call automatically a state-changing function in meteor without the submit confirmation in metamask. Therefore i read about using ethereumjs-tx but i don't know how to sign the method call to get this smart contract method automatically running. Pleas i can't find a answer anywhere: The current code i have in my script:

const EthereumTx = require('ethereumjs-tx')
const privateKey = Buffer.from('my private key', 'hex')
const txParams = {
  nonce: '0x00',
  gasPrice: '0x09184e72a000', 
  gasLimit: '0x2710',
  to: contractAdress, 
  value: '0x00', 
  data: contractdata,
  // EIP 155 chainId - mainnet: 1, ropsten: 3
  chainId: 3
const tx = new EthereumTx(txParams)
const serializedTx = tx.serialize()

How has the method call look like, something like this? myContractInstance.setFinised(true, what to insert here?, function(err, res){});

2 Answers 2

function(err, hash) {
  if (!err)

Here you will find example how to do it: https://github.com/ethereum/wiki/wiki/JavaScript-API#web3ethsendrawtransaction

  • Be aware though, this is for ^0.17.0 beta. sendRawTransaction is not available in 1.0.0 beta Commented Jan 16, 2018 at 6:03

Not like that but you can call your function via data like enter image description here const txParams = { data: HERE, // EIP 155 chainId - mainnet: 1, ropsten: 3 chainId: 3 }

and then call

web3.eth.sendRawTransaction('0x' + serializedTx.toString('hex'), function(err, hash) { if (!err) console.log(hash); // "0x7f9fade1c0d57a7af66ab4ead79fade1c0d57a7af66ab4ead7c2c2eb7b11a91385" });

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