Exit process after sending multiple tx asynchronously

Question

I have written a function that allows me to send an arbitrary amount of transactions, asynchronously, to my smart contract. However the process stays open even after the last transaction has finished. Currently, I have to manually press CTRL+C to exit. I would like for my program to automatically exit once the last transaction has finished. How would I go about doing this?

async function multipleTx(n) {
  accounts = await web3.eth.getAccounts()
  let totalGasUsed = 0
  for (let i = 0; i < n; i++) {
    instance.methods
      .addSubmission(i, i, i, i)
      .send({
        from: accounts[0],
        gasPrice: 10000000000,
      })
      .then((receipt) => {
        console.log(receipt)
        totalGasUsed += receipt.gasUsed
        console.log(totalGasUsed)
      })
  }
}

Answer 1

You can use Promise.all and the use process.exit(0) to deal with this problem.

It should work as you want:

async function multipleTx(n) {
  accounts = await web3.eth.getAccounts();
  let totalGasUsed = 0;

  const promisesArr = []; // make empty array
  for (let i = 0; i < n; i++) {
    promisesArr.push( // add promises to array
      instance.methods.addSubmission(i, i, i, i).send({
        from: accounts[0],
        gasPrice: 10000000000,
      })
    );
  }

  // Execute all promises and then exit process
  Promise.all(promisesArr).then((receipts) => {
    receipts.forEach((receipt) => {
      totalGasUsed += receipt.gasUsed;
    });

    console.log('Total gas used:', totalGasUsed);
    process.exit(0);
  });
}