meshcentral
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Web based remote computer management server
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JavaScript
import RegisterLoader from 'es-module-loader/core/register-loader.js';
import { InternalModuleNamespace as ModuleNamespace } from 'es-module-loader/core/loader-polyfill.js';
import { baseURI, global, isBrowser } from 'es-module-loader/core/common.js';
import { resolveIfNotPlain } from 'es-module-loader/core/resolve.js';
var loader;
// <script type="module"> support
var anonSources = {};
if (typeof document != 'undefined' && document.getElementsByTagName) {
var handleError = function(err) {
// dispatch an error event so that we can display in errors in browsers
// that don't yet support unhandledrejection
if (window.onunhandledrejection === undefined) {
try {
var evt = new Event('error');
} catch (_eventError) {
var evt = document.createEvent('Event');
evt.initEvent('error', true, true);
}
evt.message = err.message;
if (err.fileName) {
evt.filename = err.fileName;
evt.lineno = err.lineNumber;
evt.colno = err.columnNumber;
} else if (err.sourceURL) {
evt.filename = err.sourceURL;
evt.lineno = err.line;
evt.colno = err.column;
}
evt.error = err;
window.dispatchEvent(evt);
}
// throw so it still shows up in the console
throw err;
}
var ready = function() {
document.removeEventListener('DOMContentLoaded', ready, false );
var anonCnt = 0;
var scripts = document.getElementsByTagName('script');
for (var i = 0; i < scripts.length; i++) {
var script = scripts[i];
if (script.type == 'module' && !script.loaded) {
script.loaded = true;
if (script.src) {
loader.import(script.src).catch(handleError);
}
// anonymous modules supported via a custom naming scheme and registry
else {
var uri = './<anon' + ++anonCnt + '>.js';
if (script.id !== ""){
uri = "./" + script.id;
}
var anonName = resolveIfNotPlain(uri, baseURI);
anonSources[anonName] = script.innerHTML;
loader.import(anonName).catch(handleError);
}
}
}
}
// simple DOM ready
if (document.readyState !== 'loading')
setTimeout(ready);
else
document.addEventListener('DOMContentLoaded', ready, false);
}
function BrowserESModuleLoader(baseKey) {
if (baseKey)
this.baseKey = resolveIfNotPlain(baseKey, baseURI) || resolveIfNotPlain('./' + baseKey, baseURI);
RegisterLoader.call(this);
var loader = this;
// ensure System.register is available
global.System = global.System || {};
if (typeof global.System.register == 'function')
var prevRegister = global.System.register;
global.System.register = function() {
loader.register.apply(loader, arguments);
if (prevRegister)
prevRegister.apply(this, arguments);
};
}
BrowserESModuleLoader.prototype = Object.create(RegisterLoader.prototype);
// normalize is never given a relative name like "./x", that part is already handled
BrowserESModuleLoader.prototype[RegisterLoader.resolve] = function(key, parent) {
var resolved = RegisterLoader.prototype[RegisterLoader.resolve].call(this, key, parent || this.baseKey) || key;
if (!resolved)
throw new RangeError('ES module loader does not resolve plain module names, resolving "' + key + '" to ' + parent);
return resolved;
};
function xhrFetch(url, resolve, reject) {
var xhr = new XMLHttpRequest();
var load = function(source) {
resolve(xhr.responseText);
}
var error = function() {
reject(new Error('XHR error' + (xhr.status ? ' (' + xhr.status + (xhr.statusText ? ' ' + xhr.statusText : '') + ')' : '') + ' loading ' + url));
}
xhr.onreadystatechange = function () {
if (xhr.readyState === 4) {
// in Chrome on file:/// URLs, status is 0
if (xhr.status == 0) {
if (xhr.responseText) {
load();
}
else {
// when responseText is empty, wait for load or error event
// to inform if it is a 404 or empty file
xhr.addEventListener('error', error);
xhr.addEventListener('load', load);
}
}
else if (xhr.status === 200) {
load();
}
else {
error();
}
}
};
xhr.open("GET", url, true);
xhr.send(null);
}
var WorkerPool = function (script, size) {
var current = document.currentScript;
// IE doesn't support currentScript
if (!current) {
// Find an entry with out basename
var scripts = document.getElementsByTagName('script');
for (var i = 0; i < scripts.length; i++) {
if (scripts[i].src.indexOf("browser-es-module-loader.js") !== -1) {
current = scripts[i];
break;
}
}
if (!current)
throw Error("Could not find own <script> element");
}
script = current.src.substr(0, current.src.lastIndexOf("/")) + "/" + script;
this._workers = new Array(size);
this._ind = 0;
this._size = size;
this._jobs = 0;
this.onmessage = undefined;
this._stopTimeout = undefined;
for (var i = 0; i < size; i++) {
var wrkr = new Worker(script);
wrkr._count = 0;
wrkr._ind = i;
wrkr.onmessage = this._onmessage.bind(this, wrkr);
wrkr.onerror = this._onerror.bind(this);
this._workers[i] = wrkr;
}
this._checkJobs();
};
WorkerPool.prototype = {
postMessage: function (msg) {
if (this._stopTimeout !== undefined) {
clearTimeout(this._stopTimeout);
this._stopTimeout = undefined;
}
var wrkr = this._workers[this._ind % this._size];
wrkr._count++;
this._jobs++;
wrkr.postMessage(msg);
this._ind++;
},
_onmessage: function (wrkr, evt) {
wrkr._count--;
this._jobs--;
this.onmessage(evt, wrkr);
this._checkJobs();
},
_onerror: function(err) {
try {
var evt = new Event('error');
} catch (_eventError) {
var evt = document.createEvent('Event');
evt.initEvent('error', true, true);
}
evt.message = err.message;
evt.filename = err.filename;
evt.lineno = err.lineno;
evt.colno = err.colno;
evt.error = err.error;
window.dispatchEvent(evt);
},
_checkJobs: function () {
if (this._jobs === 0 && this._stopTimeout === undefined) {
// wait for 2s of inactivity before stopping (that should be enough for local loading)
this._stopTimeout = setTimeout(this._stop.bind(this), 2000);
}
},
_stop: function () {
this._workers.forEach(function(wrkr) {
wrkr.terminate();
});
}
};
var promiseMap = new Map();
var babelWorker = new WorkerPool('babel-worker.js', 3);
babelWorker.onmessage = function (evt) {
var promFuncs = promiseMap.get(evt.data.key);
promFuncs.resolve(evt.data);
promiseMap.delete(evt.data.key);
};
// instantiate just needs to run System.register
// so we fetch the source, convert into the Babel System module format, then evaluate it
BrowserESModuleLoader.prototype[RegisterLoader.instantiate] = function(key, processAnonRegister) {
var loader = this;
// load as ES with Babel converting into System.register
return new Promise(function(resolve, reject) {
// anonymous module
if (anonSources[key]) {
resolve(anonSources[key])
anonSources[key] = undefined;
}
// otherwise we fetch
else {
xhrFetch(key, resolve, reject);
}
})
.then(function(source) {
// check our cache first
var cacheEntry = localStorage.getItem(key);
if (cacheEntry) {
cacheEntry = JSON.parse(cacheEntry);
// TODO: store a hash instead
if (cacheEntry.source === source) {
return Promise.resolve({key: key, code: cacheEntry.code, source: cacheEntry.source});
}
}
return new Promise(function (resolve, reject) {
promiseMap.set(key, {resolve: resolve, reject: reject});
babelWorker.postMessage({key: key, source: source});
});
}).then(function (data) {
// evaluate without require, exports and module variables
// we leave module in for now to allow module.require access
try {
var cacheEntry = JSON.stringify({source: data.source, code: data.code});
localStorage.setItem(key, cacheEntry);
} catch (e) {
if (window.console) {
window.console.warn('Unable to cache transpiled version of ' + key + ': ' + e);
}
}
(0, eval)(data.code + '\n//# sourceURL=' + data.key + '!transpiled');
processAnonRegister();
});
};
// create a default loader instance in the browser
if (isBrowser)
loader = new BrowserESModuleLoader();
export default BrowserESModuleLoader;