async-waterpark

Simple async module for JavaScript, that supports sequences and repeats.

Runs a set functions in series, each passing their results to the next in the array, or optionally, re-running itself.

However, if any of the functions pass an error to the callback, the next function is not executed and the main callback is immediately called with the error.

For browsers and node.js.

Installation

• Just include async-waterpark before your scripts.
• npm install async-waterpark if you’re using node.js.
• component install jonathanconway/async-waterpark if you’re using component(1).
• bower install async-waterpark if you’re using Twitter Bower.

Usage

• waterpark(tasks...);
• tasks - A series of functions to run, each passed in as a parameter. Each function receives as its first parameter iteration, an object containing methods by which to control the flow. On completion, it must call one of those methods. All subsequent parameters are simply the values that were passed to iteration.done() or iteration.repeat() by the previous iteration, if there was one. ** iteration.done([params...]) - proceed to the next task in the series, passing any parameters specified to that function. ** iteration.repeat([params...]) - re-run the current task, passing any parameters specified to the function.

Node.js:

var waterpark = require('async-waterpark');
waterpark(tasks);

Browser:

// component(1)
var waterpark = require('async-waterpark');
waterpark(tasks);

// Default:
window.asyncWaterpark(tasks);

Three tasks, run in sequence

var waterpark = require('async-waterpark');
waterpark(
  function (iteration) {
    console.log('running one');
    iteration.done(123);
  },
  function (iteration, data) {
    console.log('running two');
    console.log('data: ', data)
    iteration.done();
  },
  function (iteration, message) {
    console.log('running three');
  });

Three tasks, run in sequence, with the 2nd task retried once

var waterpark = require('async-waterpark');
waterpark(
  function (iteration) {
    console.log('running one');
    iteration.done();
  },
  function (iteration, retried) {
    console.log('running two');
    if (retried) {
      console.log('two done')
      iteration.done();
    } else {
      console.log('two will repeat')
      iteration.repeat(true);
    }
  },
  function (iteration, message) {
    console.log('running three');
  });

Acknowledgements

Big thanks to Elan Shanker for inspiration.

License

MIT