Ghost/core/server/ghost-server.js

// # Ghost Server
// Handles the creation of an HTTP Server for Ghost
var Promise = require('bluebird'),
    chalk = require('chalk'),
    fs = require('fs'),
    semver = require('semver'),
    packageInfo = require('../../package.json'),
    errors = require('./errors'),
    config = require('./config');

/**
 * ## GhostServer
 * @constructor
 * @param {Object} rootApp - parent express instance
 */
function GhostServer(rootApp) {
    this.rootApp = rootApp;
    this.httpServer = null;
    this.connections = {};
    this.connectionId = 0;
    this.upgradeWarning = setTimeout(this.logUpgradeWarning.bind(this), 5000);

    // 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
 */
GhostServer.prototype.start = function (externalApp) {
    var self = this,
        rootApp = externalApp ? externalApp : self.rootApp;

    return new Promise(function (resolve) {
        var socketConfig = config.getSocket();

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

            self.httpServer = rootApp.listen(socketConfig.path);

            fs.chmod(socketConfig.path, socketConfig.permissions);
        } else {
            self.httpServer = rootApp.listen(
                config.server.port,
                config.server.host
            );
        }

        self.httpServer.on('error', function (error) {
            if (error.errno === 'EADDRINUSE') {
                errors.logError(
                    '(EADDRINUSE) Cannot start Ghost.',
                    'Port ' + config.server.port + ' is already in use by another program.',
                    'Is another Ghost instance already running?'
                );
            } else {
                errors.logError(
                    '(Code: ' + error.errno + ')',
                    'There was an error starting your server.',
                    'Please use the error code above to search for a solution.'
                );
            }
            process.exit(-1);
        });
        self.httpServer.on('connection', self.connection.bind(self));
        self.httpServer.on('listening', function () {
            self.logStartMessages();
            clearTimeout(self.upgradeWarning);
            resolve(self);
        });
    });
};

/**
 * ### 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
 */
GhostServer.prototype.stop = function () {
    var self = this;

    return new Promise(function (resolve) {
        if (self.httpServer === null) {
            resolve(self);
        } else {
            self.httpServer.close(function () {
                self.httpServer = null;
                self.logShutdownMessages();
                resolve(self);
            });

            self.closeConnections();
        }
    });
};

/**
 * ### Restart
 * Restarts the ghost application
 * @returns {Promise} Resolves once Ghost has restarted
 */
GhostServer.prototype.restart = function () {
    return this.stop().then(this.start.bind(this));
};

/**
 * ### Hammertime
 * To be called after `stop`
 */
GhostServer.prototype.hammertime = function () {
    console.log(chalk.green('Can\'t touch this'));

    return Promise.resolve(this);
};

/**
 * ## Private (internal) methods
 *
 * ### Connection
 * @param {Object} socket
 */
GhostServer.prototype.connection = function (socket) {
    var self = this;

    self.connectionId += 1;
    socket._ghostId = self.connectionId;

    socket.on('close', function () {
        delete self.connections[this._ghostId];
    });

    self.connections[socket._ghostId] = socket;
};

/**
 * ### Close Connections
 * Most browsers keep a persistent connection open to the server, which prevents the close callback of
 * httpServer from returning. We need to destroy all connections manually.
 */
GhostServer.prototype.closeConnections = function () {
    var self = this;

    Object.keys(self.connections).forEach(function (socketId) {
        var socket = self.connections[socketId];

        if (socket) {
            socket.destroy();
        }
    });
};

/**
 * ### Log Start Messages
 */
GhostServer.prototype.logStartMessages = function () {
    // Tell users if their node version is not supported, and exit
    if (!semver.satisfies(process.versions.node, packageInfo.engines.node) &&
        !semver.satisfies(process.versions.node, packageInfo.engines.iojs)) {
        console.log(
            chalk.red('\nERROR: Unsupported version of Node'),
            chalk.red('\nGhost needs Node version'),
            chalk.yellow(packageInfo.engines.node),
            chalk.red('you are using version'),
            chalk.yellow(process.versions.node),
            chalk.green('\nPlease go to http://nodejs.org to get a supported version')
        );

        process.exit(0);
    }

    // Startup & Shutdown messages
    if (process.env.NODE_ENV === 'production') {
        console.log(
            chalk.green('Ghost is running...'),
            '\nYour blog is now available on',
            config.url,
            chalk.gray('\nCtrl+C to shut down')
        );
    } else {
        console.log(
            chalk.green('Ghost is running in ' + process.env.NODE_ENV + '...'),
            '\nListening on',
                config.getSocket() || config.server.host + ':' + config.server.port,
            '\nUrl configured as:',
            config.url,
            chalk.gray('\nCtrl+C to shut down')
        );
    }

    function shutdown() {
        console.log(chalk.red('\nGhost has shut down'));
        if (process.env.NODE_ENV === 'production') {
            console.log(
                '\nYour blog is now offline'
            );
        } else {
            console.log(
                '\nGhost was running for',
                Math.round(process.uptime()),
                'seconds'
            );
        }
        process.exit(0);
    }
    // ensure that Ghost exits correctly on Ctrl+C and SIGTERM
    process.
        removeAllListeners('SIGINT').on('SIGINT', shutdown).
        removeAllListeners('SIGTERM').on('SIGTERM', shutdown);
};

/**
 * ### Log Shutdown Messages
 */
GhostServer.prototype.logShutdownMessages = function () {
    console.log(chalk.red('Ghost is closing connections'));
};

/**
 * ### Log Upgrade Warning
 * Warning that the API for the node module version of Ghost changed in 0.5.2
 *
 * *This should be removed soon*
 */
GhostServer.prototype.logUpgradeWarning = function () {
    errors.logWarn(
        'Ghost no longer starts automatically when using it as an npm module.',
        'If you\'re seeing this message, you may need to update your custom code.',
        'Please see the docs at http://tinyurl.com/npm-upgrade for more information.'
    );
};

module.exports = GhostServer;