server/SpellChecker/sources/server.js

/*
 * (c) Copyright Ascensio System SIA 2010-2019
 *
 * This program is a free software product. You can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License (AGPL)
 * version 3 as published by the Free Software Foundation. In accordance with
 * Section 7(a) of the GNU AGPL its Section 15 shall be amended to the effect
 * that Ascensio System SIA expressly excludes the warranty of non-infringement
 * of any third-party rights.
 *
 * This program is distributed WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For
 * details, see the GNU AGPL at: http://www.gnu.org/licenses/agpl-3.0.html
 *
 * You can contact Ascensio System SIA at 20A-12 Ernesta Birznieka-Upisha
 * street, Riga, Latvia, EU, LV-1050.
 *
 * The  interactive user interfaces in modified source and object code versions
 * of the Program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU AGPL version 3.
 *
 * Pursuant to Section 7(b) of the License you must retain the original Product
 * logo when distributing the program. Pursuant to Section 7(e) we decline to
 * grant you any rights under trademark law for use of our trademarks.
 *
 * All the Product's GUI elements, including illustrations and icon sets, as
 * well as technical writing content are licensed under the terms of the
 * Creative Commons Attribution-ShareAlike 4.0 International. See the License
 * terms at http://creativecommons.org/licenses/by-sa/4.0/legalcode
 *
 */

'use strict';

const cluster = require('cluster');
const config = require('config').get('SpellChecker');

//process.env.NODE_ENV = config.get('server.mode');

const logger = require('./../../Common/sources/logger');

const c_nCheckHealth = 60000, c_sCheckWord = 'color', c_sCheckLang = 1033;
let idCheckInterval, canStartCheck = true;
let statusCheckHealth = true;
function checkHealth (worker) {
	logger.info('checkHealth');
	if (!statusCheckHealth) {
		logger.error('error check health, restart!');
		worker.kill();
		return;
	}
	worker.send({type: 'spell'});
	statusCheckHealth = false;
}
function endCheckHealth (msg) {
	logger.info('endCheckHealth');
	statusCheckHealth = true;
}

const workersCount = 1;	// ToDo Пока только 1 процесс будем задействовать. Но в будующем стоит рассмотреть несколько.
if (cluster.isMaster) {
	logger.warn('start cluster with %s workers', workersCount);
	cluster.on('listening', function(worker) {
		if (canStartCheck) {
			canStartCheck = false;
			idCheckInterval = setInterval(function(){checkHealth(worker);}, c_nCheckHealth);
			worker.on('message', function(msg){endCheckHealth(msg);});
		}
	});
	for (let nIndexWorker = 0; nIndexWorker < workersCount; ++nIndexWorker) {
		logger.warn('worker %s started.', cluster.fork().process.pid);
	}

	cluster.on('exit', (worker, code, signal) => {
		logger.warn('worker %s died (code = %s; signal = %s). restart...', worker.process.pid, code, signal);
		clearInterval(idCheckInterval);
		endCheckHealth();
		canStartCheck = true;
		cluster.fork();
	});
} else {
	const express = require('express'),
		http = require('http'),
		https = require('https'),
		fs = require("fs"),
		app = express(),
		spellCheck  = require('./spellCheck');
	let server = null;


	logger.warn('Express server starting...');

	if (config.has('ssl')) {
		const privateKey = fs.readFileSync(config.get('ssl.key')).toString();
		const certificateKey = fs.readFileSync(config.get('ssl.cert')).toString();
		const trustedCertificate = fs.readFileSync(config.get('ssl.ca')).toString();
		//See detailed options format here: http://nodejs.org/api/tls.html#tls_tls_createserver_options_secureconnectionlistener
		const options = {key: privateKey, cert: certificateKey, ca: [trustedCertificate]};

		server = https.createServer(options, app);
	} else {
		server = http.createServer(app);
	}

	// Если захочется использовать 'development' и 'production',
	// то с помощью app.settings.env (https://github.com/strongloop/express/issues/936)
	// Если нужна обработка ошибок, то теперь она такая https://github.com/expressjs/errorhandler
	spellCheck.install(server, function(){
		server.listen(config.get('server.port'), function(){
			logger.warn("Express server listening on port %d in %s mode", config.get('server.port'), app.settings.env);
		});

		app.get('/index.html', function(req, res) {
			res.send('Server is functioning normally');
		});
	});

	process.on('message', function(msg) {
		if (!spellCheck)
			return;
		spellCheck.spellSuggest(msg.type, c_sCheckWord, c_sCheckLang, function(res) {
			process.send({type: msg.type, res: res});
		});
	});

	process.on('uncaughtException', function(err) {
		logger.error((new Date).toUTCString() + ' uncaughtException:', err.message);
		logger.error(err.stack);
		logger.shutdown(function () {
			process.exit(1);
		});
	});
}