How do you estimate the and set the gasPrice / gasLimit in a method?

[stoplion]

How do you estimate the and set the gasPrice / gasLimit in a method?

I've got the following, but the method fails because of gas issues..

Using Ethers 5.0.31

var estimateGas = await myContract.estimateGas.myMethod('test', {value: 0.00056*10e18 })
// returns 50584

const gasPriceBigNumber = await web3Provider.getGasPrice()
const gasPrice = gasPriceBigNumber.toNumber()

const response = await myContract.myMethod(
       "test"
        {
          value: [this method is payable, send some Eth],
          gasPrice,
          gasLimit: estimateGas,
        }

Also..

Is the gasPrice set in wei or gwei? Ditto for gasLimit...

[ricmoo]

Heya!

First note is to never use JavaScript numbers when working with Ethereum (see here why), so you should probably replace your 0.00056*10e18 with ethers.utils.parseEther("0.0056").

The gas price is always in wei, there isn't really a unit for gasLimit, it is simply the number of units of gas you are permitting your call to take up to.

Otherwise, your code looks like it should work. What is the error? Keep in mind there are plenty of reasons the contract may not work, it may have a require that is failing, could be throwing an exception or reverting.

Is your contract mined? Or is it failing before that?

[ricmoo]

(I'm moving this issue to discussions. :))

[stoplion]

The call to const gasPrice = (await web3Provider.getGasPrice()).toNumber() returns 5000000000

The 5000000000 is Wei right? That would make the Gwei price 5?

The current gas price is around 188. Trying to figure out how to get that value with getGasPrice()

I must be doing something wrong between getGasPrice() and setting the gasPrice in the overrides..

{
          value,
          gasPrice: gasPriceInWei, 
          gasLimit: 60500,

[ricmoo]

That is the Kovan testnet in your Metamask image. The gas price is around 188 on Mainnet right now.

Each network has wildly different pas prices at any given time. :)

[stoplion]

Yup. That was it. Switched nets, and it's coming back around 188. 🤙🏻