promise.js

const produceData = () => {
  getData()
    .then(result1 => processResult1(result1))
    .then(result2 => processResult2(result2))
    .then(result3 => return(result3))
    .catch (error) => {
      return error
    }
}

// Produce and Return Data
produceData()
  .then(data => sendToClient(data))