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web worker as a promise
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| // Usage | |
| var workerFibo = createPromiseWorker(function(x){ | |
| return (function fibo(n){ | |
| if (n > 1) { | |
| return fibo(n - 1) + fibo(n - 2); | |
| } else { | |
| return 1; | |
| } | |
| })(x) | |
| }); | |
| Promise.all([0, 1, 2, 3, 5, 8, 13, 21, 34].map(workerFibo)).then(console.log); | |
| // Module | |
| var Worker = require('webworker-threads').Worker; | |
| var Promise = require('promise'); | |
| var fnRegex = require('function-regex'); | |
| function toArray (arr) { return Array.prototype.slice.call(arr) } | |
| function parseFunction(fn) { | |
| if (typeof fn === 'function') { | |
| fn = fn.toString(); | |
| } | |
| var match = fnRegex().exec(fn); | |
| var _parameters = match[2] || ''; | |
| var _arguments = _parameters.length && _parameters.replace(/\s/g, '').split(',') || []; | |
| return { | |
| name: match[1] || 'anonymous', | |
| arguments: _arguments, | |
| body: match[3] || '' | |
| }; | |
| }; | |
| module.exports = function createPromiseWorker(compute) { | |
| var i = 0; | |
| var parsedCompute = parseFunction(compute); | |
| var promises = []; | |
| var worker = new Worker(function () { | |
| onmessage = function (e) { | |
| var fn = e.data.method; | |
| var method = Function.apply(null, fn.arguments.concat(fn.body)) | |
| try { | |
| var results = method.apply(null, e.data.arguments); | |
| postMessage({ | |
| type: 'success', | |
| data: results, | |
| id: e.data.id | |
| }); | |
| } catch (err) { | |
| postMessage({ | |
| type: 'fail', | |
| data: err, | |
| id: e.data.id | |
| }); | |
| } | |
| // this.close() | |
| } | |
| }); | |
| worker.addEventListener('message', function (e) { | |
| (e.data.type === 'success' | |
| ? promises[e.data.id].resolve | |
| : promises[e.data.id].reject | |
| )(e.data.data); | |
| }, false); | |
| return function(){ | |
| var args = toArray(arguments); | |
| return new Promise(function(resolve, reject){ | |
| var id = i++; | |
| promises[id] = {resolve: resolve, reject: reject}; | |
| worker.postMessage({ | |
| method: parsedCompute, | |
| arguments: args, | |
| id: id | |
| }); | |
| }); | |
| } | |
| } | |
| /* read | |
| * http://www.html5rocks.com/en/tutorials/workers/basics/ | |
| * http://developerblog.redhat.com/2014/05/20/communicating-large-objects-with-web-workers-in-javascript/ | |
| * | |
| * function decompilation | |
| * http://perfectionkills.com/state-of-function-decompilation-in-javascript/ | |
| * http://stackoverflow.com/questions/3179861/javascript-get-function-body | |
| * */ |
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