chainbuilder-flow

Flow block (each, map, if, while) mixins for chainbuilder.

Installation npm install chainbuilder chainbuilder-flow --save

Usage

var chainBuilder = require('chainbuilder');

var myChain = chainBuilder({
  methods: {/* ... your methods ... */},
  mixins: [
    /* ... other mixins ... */
    require('chainbuilder-flow')()
  ]
});

Methods

#$beginMap(options), #$endMap()

Begin and end a map block. The map will be made in parallel by default.

e.g.

myChain([1, 2, 3])
  .$beginMap({ series: true })
    .add(1)
    .times(2)
  .$endMap()
  .end(function (err, result) {
    console.log(result); // > [4, 6, 8]
  });

@param {Object} options (optional) flow control options. @param {Boolean} options.series (optional) run the block in series (one at a time). @param {Number} options.limit (optional) limit to running n items in parallel at a time. @alias #$beginEach(options), #$endEach()

#$beginIf(conditionFn), #$endIf()

Begin and end a conditional block.

e.g.

myChain(2)

  .$beginIf(function (result) { return result === 1; })
    .inject(3)
  .$endIf()
  .end(function (err, result) { console.log(result); // > 2 })
  
  .$beginIf(function (result) { return result === 2; })
    .inject(3)
  .$endIf()
  .end(function (err, result) { console.log(result); // > 3 });

@param {function(result):boolean} conditionFn block will run if true is returned.

#$beginWhile(checkFn), #$endWhile()

Begin and end a block that is executed while the condition is true.

e.g.

myChain(1)
  .$beginWhile(function (result) { return result < 4; })
    .transform(function (err, result, done) { done(null, result + 1); })
  .$endWhile()
  .end(function (err, result) { console.log(result); // > 4 })

@param {function(result):boolean} conditionFn block will run while true is returned.