manet/src/manet.js

Website screenshot service powered by Node.js, SlimerJS and PhantomJS

"use strict";

const _ = require('lodash'),
      express = require('express'),
      bodyParser = require('body-parser'),
      logger = require('winston'),
      fs = require('fs-extra'),
      nocache = require('nocache'),
      passport = require('passport'),
      config = require('./config'),
      routes = require('./routes'),
      filters = require('./filters'),
      utils = require('./utils'),

      DEF_LOGGER_LEVEL = 'info',
      DEF_LOGGER_SILENT = false;


/* Logging system */

function initLogging(conf) {
    logger.setLevels({
        error: 0,
        warn: 1,
        info: 2,
        verbose: 3,
        debug: 4,
        silly: 5
    });
    logger.addColors({
        debug: 'green',
        info: 'cyan',
        silly: 'magenta',
        warn: 'yellow',
        error: 'red'
    });

    logger.remove(logger.transports.Console);
    logger.add(logger.transports.Console, {
        level: conf.level || DEF_LOGGER_LEVEL,
        silent: conf.silent || DEF_LOGGER_SILENT,
        colorize: true,
        timestamp: true
    });
}


/* Termination & Errors handling */

function initExitHandling(server) {
    const onExit = () => {
        server.close(() => {
            logger.info('Manet server stopped');
            process.exit(0);
        });
    };

    process.on('SIGTERM', onExit);
    process.on('SIGINT', onExit);
}


/* Init FS services */

function cleanupFsStorage(conf) {
    if (conf.cleanupStartup) {
        const storagePath = conf.storage,
              files = fs.readdirSync(storagePath);

        files.forEach((file) => {
            try {
                const filePath = utils.filePath(file, storagePath);
                fs.removeSync(filePath, {force: true});
            } catch (err) {}
        });
    }
}

function initFsWatchdog(conf) {
    const timeout = conf.cache * 1000,
          dir = conf.storage;

    utils.runFsWatchdog(dir, timeout, (file) => {
        fs.unlink(file, (err) => {
            if (err) {
                logger.debug('Can not delete file "%s": %s', file, err);
            } else {
                logger.info('Deleted file "%s"', file);
            }
        });
    });
}

function initFsStorage(conf) {
    cleanupFsStorage(conf);
    initFsWatchdog(conf);
}


/* Web application */

function createWebApplication(conf) {
    const app = express(),
          index = routes.index(conf),
          urlencoded = bodyParser.urlencoded({ extended: false }),
          json = bodyParser.json(),
          noCache = nocache(),
          basic = filters.basic(conf),
          usage = filters.usage(conf),
          merge = filters.merge,
          notNull = (f) => _.without(f, null);

    filters.configureWebSecurity(conf);

    app.use(express.static(utils.filePath('../public')));
    app.use(passport.initialize());

    app.get('/', notNull([noCache, basic, merge, usage]), index);
    app.post('/', notNull([noCache, basic, urlencoded, json, merge, usage]), index);

    return app;
}

function runWebServer(conf, onStart) {
    const app = createWebApplication(conf),
          host = conf.host,
          port = conf.port,
          server = app.listen(port, host, () => {
              if (onStart) {
                  onStart(server);
              }
          });

    logger.info('Manet server started on %s:%d', host, port);

    initExitHandling(server);
}


/* Initialize and run server */

function main(onStart) {
    const conf = config.read();

    initLogging(conf);
    initFsStorage(conf);

    logger.debug('Default configuration file: %s', conf.path);
    logger.debug('Configuration parameters: %s', JSON.stringify(conf));

    runWebServer(conf, onStart);
}


/* Exported functions */

module.exports = {
    main: main
};