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web-worker-helper

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Utilities for running tasks on worker threads

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"use strict"; var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) { function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); } return new (P || (P = Promise))(function (resolve, reject) { function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } } function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } } function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); } step((generator = generator.apply(thisArg, _arguments || [])).next()); }); }; var __generator = (this && this.__generator) || function (thisArg, body) { var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g; return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g; function verb(n) { return function (v) { return step([n, v]); }; } function step(op) { if (f) throw new TypeError("Generator is already executing."); while (g && (g = 0, op[0] && (_ = 0)), _) try { if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t; if (y = 0, t) op = [op[0] & 2, t.value]; switch (op[0]) { case 0: case 1: t = op; break; case 4: _.label++; return { value: op[1], done: false }; case 5: _.label++; y = op[1]; op = [0]; continue; case 7: op = _.ops.pop(); _.trys.pop(); continue; default: if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; } if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; } if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; } if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; } if (t[2]) _.ops.pop(); _.trys.pop(); continue; } op = body.call(thisArg, _); } catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; } if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true }; } }; Object.defineProperty(exports, "__esModule", { value: true }); exports.getLibraryUrl = exports.loadLibrary = void 0; /* global importScripts */ var globals_1 = require("../env-utils/globals"); var assert_1 = require("../env-utils/assert"); var loadLibraryPromises = {}; // promises /** * Dynamically loads a library ("module") * * - wasm library: Array buffer is returned * - js library: Parse JS is returned * * Method depends on environment * - browser - script element is created and installed on document * - worker - eval is called on global context * - node - file is required * * @param libraryUrl * @param moduleName * @param options */ function loadLibrary(libraryUrl_1) { return __awaiter(this, arguments, void 0, function (libraryUrl, moduleName, options) { if (moduleName === void 0) { moduleName = null; } if (options === void 0) { options = {}; } return __generator(this, function (_a) { switch (_a.label) { case 0: if (moduleName) { libraryUrl = getLibraryUrl(libraryUrl, moduleName, options); } // Ensure libraries are only loaded once loadLibraryPromises[libraryUrl] = loadLibraryPromises[libraryUrl] || loadLibraryFromFile(libraryUrl); return [4 /*yield*/, loadLibraryPromises[libraryUrl]]; case 1: return [2 /*return*/, _a.sent()]; } }); }); } exports.loadLibrary = loadLibrary; // TODO - sort out how to resolve paths for main/worker and dev/prod function getLibraryUrl(library, moduleName, options) { // Check if already a URL if (library.startsWith('http')) { return library; } // Allow application to import and supply libraries through `options.modules` var modules = options.modules || {}; if (modules[library]) { return modules[library]; } // load from external scripts if (options.CDN) { (0, assert_1.assert)(options.CDN.startsWith('http')); return "".concat(options.CDN, "/").concat(moduleName, "/dist/libs/").concat(library); } // TODO - loading inside workers requires paths relative to worker script location... if (globals_1.isWorker) { return "../src/libs/".concat(library); } return "modules/".concat(moduleName, "/src/libs/").concat(library); } exports.getLibraryUrl = getLibraryUrl; function loadLibraryFromFile(libraryUrl) { return __awaiter(this, void 0, void 0, function () { var response_1, response, scriptSource; return __generator(this, function (_a) { switch (_a.label) { case 0: if (!libraryUrl.endsWith('wasm')) return [3 /*break*/, 3]; return [4 /*yield*/, fetch(libraryUrl)]; case 1: response_1 = _a.sent(); return [4 /*yield*/, response_1.arrayBuffer()]; case 2: return [2 /*return*/, _a.sent()]; case 3: if (globals_1.isWorker) { return [2 /*return*/, importScripts(libraryUrl)]; } return [4 /*yield*/, fetch(libraryUrl)]; case 4: response = _a.sent(); return [4 /*yield*/, response.text()]; case 5: scriptSource = _a.sent(); return [2 /*return*/, loadLibraryFromString(scriptSource, libraryUrl)]; } }); }); } /* async function loadScriptFromFile(libraryUrl) { const script = document.createElement('script'); script.src = libraryUrl; return await new Promise((resolve, reject) => { script.onload = data => { resolve(data); }; script.onerror = reject; }); } */ // TODO - Needs security audit... // - Raw eval call // - Potentially bypasses CORS // Upside is that this separates fetching and parsing // we could create a`LibraryLoader` or`ModuleLoader` function loadLibraryFromString(scriptSource, id) { if (globals_1.isWorker) { // Use lvalue trick to make eval run in global scope eval.call(globals_1.global, scriptSource); // eslint-disable-line no-eval // https://stackoverflow.com/questions/9107240/1-evalthis-vs-evalthis-in-javascript return null; } var script = document.createElement('script'); script.id = id; // most browsers like a separate text node but some throw an error. The second method covers those. try { script.appendChild(document.createTextNode(scriptSource)); } catch (e) { script.text = scriptSource; } document.body.appendChild(script); return null; } // TODO - technique for module injection into worker, from THREE.DracoLoader... /* function combineWorkerWithLibrary(worker, jsContent) { var fn = wWorker.toString(); var body = [ '// injected', jsContent, '', '// worker', fn.substring(fn.indexOf('{') + 1, fn.lastIndexOf('}')) ].join('\n'); this.workerSourceURL = URL.createObjectURL(new Blob([body])); } */