Promiss

This is a promises sequence runner. It will be used to run multiple promise based functions in sequence.

Usage

Installation

npm install --save promiss

Usage

promiss takes two arguments.

1. array of promises
2. options to customize response

const promiss = require('promiss');

const foo = () => {
  return Promise((resolve, reject) => {
    setTimeout((){
      resolve('hello');
    }, 3000)
  });
};
const bar = () => {
  return Promise((resolve, reject) => {
    setTimeout((){
      reject(new Error('My heart broke'));
    }, 5000)
  });
};
const zoo = () => {
  return Promise((resolve, reject) => {
    setTimeout((){
      resolve('adios');
    }, 2000)
  });
};

// throws the first error rejected
// same as passing { errors: true } as the second argument
return promiss([foo(), bar(), zoo()]).catch(err => {
  // err.message = 'My heart broke'
  // catches the first error
});

// collects all errors and resolves at the end with results
return promiss([foo, bar, zoo], { error: false }).then(results => {
  // result will look like this
  [
    {
      index: 0,
      result: 'hello',
      error: null
    },
    {
      index: 1,
      result: null,
      error: Error('My heart broke')
    },
    {
      index: 3,
      result: 'adios',
      error: null
    }
  ]
});

Options

• errors takes boolean value:
  • true: throws the first instance of error (the default behavior)
  • false: collects all the errors and returns array of objects with index, result and error
    • index: index of the method in the array passed
    • result: result if there is result and null if it throws an error
    • error: error if there is error and null if there is no error