sequential-promise-map

sequential-promise-map

A simple sequential version of Promise.map, useful to transform an array of values into asynchronous promises, when you need to limit parallel execution of promise generators (eg to prevent hitting external resource thresholds, or to guarantee that things need to happen in a particular sequence).

The function has no dependencies so it will work in Node or browsers, as long as native Promises are supported.

Installation

npm install sequential-promise-map

Usage

sequentialPromiseMap(arrayOfValues, promiseGenerator).then(....) 

The function will resolve will contain an array of Promise results, in the same order as the arguments, or reject with the first rejection.

Example

const sequentialPromiseMap = require('sequential-promise-map');

const fruits = ['apples', 'oranges', 'grapes'];

const invert = function (name) {
  return new Promise(resolve => {
    resolve(name.split('').reverse().join(''));
  });
};

sequentialPromiseMap(fruits, invert).then(results => console.log('got results', results));

License

MIT