Why does estimateGas always return null or zero?

Question

I am having some issue with the following... it might be my code or might simply be that the transactions require no gas?

They always return null or zero.

var gas = 0;
const eth = new Eth(web3.currentProvider);
const contract = new EthContract(eth);
const myContract= contract(abi);
var me = myContract.at(contractAddress);
eth.estimateGas({
        from: eth.accounts[0], 
        to: "0x0Fe18f369c7F34208922cAEBbd5d21E131E44692", 
        amount: web3.toWei(1, "ether")}, function(d){
        var gas = web3.toBigNumber(gas).toString();
        console.log(gas);                            
        if(gas.toString() != "null"){
                   gas = d; 
                    console.log("Gas: " + d);
       }
 });

Returns zero always... or null. Is this an error with my code? Or do these transactions require no gas?

Answer 1

The Web3 API uses error first style callbacks.

Your call should look like this:

eth.estimateGas({
    from: eth.accounts[0], 
    to: "0x0Fe18f369c7F34208922cAEBbd5d21E131E44692", 
    value: web3.toWei(1, "ether")
  }, 
  function(e, d) {
    var gas = web3.toBigNumber(gas).toString();
    console.log(gas);

    if (gas.toString() != "null") {
      gas = d; 
      console.log("Gas: " + d);
    }
 });