A gist to loop promise

promise-iteration-with-reduce.js

let tasks = [ /* ... */ ]
let promise = tasks.reduce((prev, task) => {
  return prev.then(() => {
    return task();
  });
}, Promise.resolve());
promise.then(() => {
//All tasks completed
});

sequential-iteration-pattern.js

let tasks = [ /* ... */ ]
let promise = Promise.resolve();
tasks.forEach(task => {
  promise = promise.then(() => {
    return task();
  });
});
promise.then(() => {
//All tasks completed
});

sequential-iteration.js

function spiderLinks(currentUrl, body, nesting) {
  let promise = Promise.resolve();
  if(nesting === 0) {
    return promise;
  }
  const links = utilities.getPageLinks(currentUrl, body);
  links.forEach(link => {
    promise = promise.then(() => spider(link, nesting - 1));
  });
  return promise;
}