Sequential Promise Execution

sequential-promise.js

const arrayOfSlackMessages = [1, 2, 3, 4, 5];
const waitTimes = [1000, 2000, 5000, 10000];

function sendSlackMessage(message, waitTime) {
  return new Promise(function (resolve, reject) {
    setTimeout(function () {
      resolve();
    }, waitTime);
  })
}

async function execute () {
  for (let message of arrayOfSlackMessages) {
    const waitTime = waitTimes[Math.floor(waitTimes.length * Math.random())];

    console.log(`Running: ${message}, Wait time:${waitTime}`);

    await sendSlackMessage(message, waitTime);

    console.log(`${message} done.`);
  }
}

execute();