32 lines
955 B
JavaScript
32 lines
955 B
JavaScript
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/**
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* # Pipeline Utility
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*
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* Based on pipeline.js from when.js:
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* https://github.com/cujojs/when/blob/3.7.4/pipeline.js
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*/
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var Promise = require('bluebird');
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function pipeline(tasks /* initial arguments */) {
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var args = Array.prototype.slice.call(arguments, 1),
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runTask = function (task, args) {
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// Self-optimizing function to run first task with multiple
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// args using apply, but subsequent tasks via direct invocation
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runTask = function (task, arg) {
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return task(arg);
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};
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return task.apply(null, args);
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};
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// Resolve any promises for the arguments passed in first
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return Promise.all(args).then(function (args) {
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// Iterate through the tasks passing args from one into the next
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return Promise.reduce(tasks, function (arg, task) {
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return runTask(task, arg);
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}, args);
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});
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}
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module.exports = pipeline;
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