Ghost/core/server/ghost-server.js

// # Ghost Server
// Handles the creation of an HTTP Server for Ghost
const debug = require('ghost-ignition').debug('server');

const Promise = require('bluebird');
const fs = require('fs-extra');
const path = require('path');
const _ = require('lodash');
const config = require('../shared/config');
const urlUtils = require('./../shared/url-utils');
const errors = require('@tryghost/errors');
const {events, i18n} = require('./lib/common');
const logging = require('../shared/logging');
const moment = require('moment');
const bootstrapSocket = require('@tryghost/bootstrap-socket');
const stoppable = require('stoppable');
const {reject} = require('bluebird');

/**
 * ## GhostServer
 */
class GhostServer {
    /**
     * @constructor
     * @param {Object} rootApp - parent express instance
     */
    constructor(rootApp) {
        this.rootApp = rootApp;
        this.httpServer = null;

        // Expose config module for use externally.
        this.config = config;
    }

    /**
     * ## Public API methods
     *
     * ### Start
     * Starts the ghost server listening on the configured port.
     * Alternatively you can pass in your own express instance and let Ghost
     * start listening for you.
     * @param  {Object} externalApp - Optional express app instance.
     * @return {Promise} Resolves once Ghost has started
     */
    start(externalApp) {
        debug('Starting...');
        const self = this;
        const rootApp = externalApp ? externalApp : self.rootApp;
        let socketConfig;

        const socketValues = {
            path: path.join(config.get('paths').contentPath, config.get('env') + '.socket'),
            permissions: '660'
        };

        return new Promise(function (resolve, reject) {
            if (Object.prototype.hasOwnProperty.call(config.get('server'), 'socket')) {
                socketConfig = config.get('server').socket;

                if (_.isString(socketConfig)) {
                    socketValues.path = socketConfig;
                } else if (_.isObject(socketConfig)) {
                    socketValues.path = socketConfig.path || socketValues.path;
                    socketValues.permissions = socketConfig.permissions || socketValues.permissions;
                }

                // Make sure the socket is gone before trying to create another
                try {
                    fs.unlinkSync(socketValues.path);
                } catch (e) {
                    // We can ignore this.
                }

                self.httpServer = rootApp.listen(socketValues.path);
                fs.chmod(socketValues.path, socketValues.permissions);
                config.set('server:socket', socketValues);
            } else {
                self.httpServer = rootApp.listen(
                    config.get('server').port,
                    config.get('server').host
                );
            }

            self.httpServer.on('error', function (error) {
                let ghostError;

                if (error.errno === 'EADDRINUSE') {
                    ghostError = new errors.GhostError({
                        message: i18n.t('errors.httpServer.addressInUse.error'),
                        context: i18n.t('errors.httpServer.addressInUse.context', {port: config.get('server').port}),
                        help: i18n.t('errors.httpServer.addressInUse.help')
                    });
                } else {
                    ghostError = new errors.GhostError({
                        message: i18n.t('errors.httpServer.otherError.error', {errorNumber: error.errno}),
                        context: i18n.t('errors.httpServer.otherError.context'),
                        help: i18n.t('errors.httpServer.otherError.help')
                    });
                }

                reject(ghostError);
            });

            self.httpServer.on('listening', function () {
                debug('...Started');
                self.logStartMessages();

                return GhostServer.announceServerReadiness()
                    .finally(() => {
                        resolve(self);
                    });
            });

            stoppable(self.httpServer, config.get('server:shutdownTimeout'));

            async function shutdown() {
                try {
                    logging.warn(i18n.t('notices.httpServer.ghostIsShuttingDown'));
                    await self.stop();
                    process.exit(0);
                } catch (error) {
                    logging.error(error);
                    process.exit(-1);
                }
            }

            // ensure that Ghost exits correctly on Ctrl+C and SIGTERM
            process
                .removeAllListeners('SIGINT').on('SIGINT', shutdown)
                .removeAllListeners('SIGTERM').on('SIGTERM', shutdown);

            if (config.get('server:testmode')) {
                // Debug code
                setInterval(() => self.httpServer.getConnections(
                    (err, connections) => logging.warn(`${connections} connections currently open`)
                ), 5000);
            }
        });
    }

    /**
     * ### Stop
     * Returns a promise that will be fulfilled when the server stops. If the server has not been started,
     * the promise will be fulfilled immediately
     * @returns {Promise} Resolves once Ghost has stopped
     */
    stop() {
        const self = this;

        return new Promise(function (resolve) {
            if (self.httpServer === null) {
                resolve(self);
            } else {
                // The stop function comes from stoppable
                self.httpServer.stop(function (err) {
                    if (err) {
                        reject(self);
                    }

                    events.emit('server.stop');
                    self.httpServer = null;
                    self.logStopMessages();
                    resolve(self);
                });
            }
        });
    }

    /**
     * ### Hammertime
     * To be called after `stop`
     */
    hammertime() {
        logging.info(i18n.t('notices.httpServer.cantTouchThis'));

        return Promise.resolve(this);
    }

    /**
     * ### Log Start Messages
     */
    logStartMessages() {
        logging.info(i18n.t('notices.httpServer.ghostIsRunningIn', {env: config.get('env')}));

        if (config.get('env') === 'production') {
            logging.info(i18n.t('notices.httpServer.yourBlogIsAvailableOn', {url: urlUtils.urlFor('home', true)}));
        } else {
            logging.info(i18n.t('notices.httpServer.listeningOn', {
                host: config.get('server').socket || config.get('server').host,
                port: config.get('server').port
            }));
            logging.info(i18n.t('notices.httpServer.urlConfiguredAs', {url: urlUtils.urlFor('home', true)}));
        }

        logging.info(i18n.t('notices.httpServer.ctrlCToShutDown'));
    }

    /**
     * ### Log Stop Messages
     */
    logStopMessages() {
        logging.warn(i18n.t('notices.httpServer.ghostHasShutdown'));

        // Extra clear message for production mode
        if (config.get('env') === 'production') {
            logging.warn(i18n.t('notices.httpServer.yourBlogIsNowOffline'));
        }

        // Always output uptime
        logging.warn(
            i18n.t('notices.httpServer.ghostWasRunningFor'),
            moment.duration(process.uptime(), 'seconds').humanize()
        );
    }
}

module.exports = GhostServer;

/**
 * We call announce server readiness when the server is ready
 * When the server is started, but not ready, it is only able to serve 503s
 *
 * If the server isn't able to reach readiness, announceServerReadiness is called with an error
 * A status message, any error, and debug info are all passed to managing processes via IPC and the bootstrap socket
 */
let announceServerReadinessCalled = false;

const debugInfo = {
    versions: process.versions,
    platform: process.platform,
    arch: process.arch,
    release: process.release
};

module.exports.announceServerReadiness = function (error = null) {
    // If we already announced readiness, we should not do it again
    if (announceServerReadinessCalled) {
        return Promise.resolve();
    }

    // Mark this function as called
    announceServerReadinessCalled = true;

    // Build our message
    // - if there's no error then the server is ready
    let message = {
        started: true,
        debug: debugInfo
    };

    // - if there's an error then the server is not ready, include the errors
    if (error) {
        message.started = false;
        message.error = error;
    } else {
        events.emit('server.start');
    }

    // CASE: IPC communication to the CLI for local process manager
    if (process.send) {
        process.send(message);
    }

    // CASE: use bootstrap socket to communicate with CLI for systemd
    let socketAddress = config.get('bootstrap-socket');
    if (socketAddress) {
        return bootstrapSocket.connectAndSend(socketAddress, logging, message);
    }

    return Promise.resolve();
};