Another example from https://scotch.io/tutorials/javascript-promises-for-dummies

promises_fetch_example.js

const sumNumbersWithApi = (a, b) => {
  const url = `https://stark-escarpment-75299.herokuapp.com/?a=${a}&b=${b}`;
  return fetch(url)
           .then(response => response.json())
           .then(response => response['response'])
           .then(response => parseInt(response))
           .catch((error) => {
             console.log("there was error:", error.message);
           });


};

const putInConsole = (response) => {
 console.log(response)
};


sumNumbersWithApi(1,2)
.then(response => sumNumbersWithApi(3, response))
.then(response => sumNumbersWithApi(3, response))
.then(response => sumNumbersWithApi(3, response))
.then(putInConsole);