sheercms/plugins/redis/redis.plugin.js

Sheer Cliff CMS is a simple and powerful content management system (CMS) for Node JS.

var logger = require('../../lib/logger');
var config = require("../../lib/config");
var redis = require('redis');
var async = require('async');

var client = null;
var _prefix = 'cms_';
var _host = '127.0.0.1';
var _port = 6379;
var _options = {};

module.exports.setOptions = function(prefix, port, host, options) {
    _prefix = prefix || 'cms_';
    _host = host || '127.0.0.1';
    _port = port || 6379;
    _options = options || {};
};

module.exports.init = function(server, done) {

    client = redis.createClient(_port, _host, _options);

    client.on("error", function (err) {
        logger.error(err);
        client.end();
        if (done) done(err);
    });

    client.on("ready", function(err) {
        if (err) {
            logger.error(err);
            if (done) done(err);
        }
        else {
            logger.info("Redis client connected.", true);
            if (done) done();
        }
    });

    //NOTE: redis module appears to close connections automatically when node exists

    /*process.on('close', function () {
        logger.warn('Redis connection disconnected through app termination.', true);
        redis.quit();
    });*/

    // If the Node process ends, close the Redis connection
    /*process.on('SIGINT', function() {
        if (client) {
            logger.warn('Redis connection disconnected through app termination.');
            client.end();
        }
    });*/
};

/*
callback: (err)
 */
module.exports.set = function(key, obj, seconds, callback) {
    try {
        //console.log("Adding to cache: " + key);
        var s = (typeof obj === 'string') ? obj : "json:" + JSON.stringify(obj);
        client.setex(_prefix + key, seconds, s, function(err, result) {
            if (err) {
                logger.error(err);
                if (callback) callback(err);
            }
            else {
                if (callback) callback(null);
            }
        });
    }
    catch(e) {
        logger.error(e);
        if (callback) callback(e);
    }
};

/*
callback: (err, value)
 */
module.exports.get = function(key, callback) {
    if (callback) {
        try {
            client.get(_prefix + key, function (err, result) {
                if (err) {
                    logger.error(err);
                    callback(err);
                }
                else if (result) {
                    //console.log("Found in cache: " + key);
                    if (result.length > 5 && result.indexOf("json:") === 0) {
                        callback(null, JSON.parse(result.substr(5)));
                    }
                    else
                        callback(null, result);
                }
                else {
                    callback(null, null);
                }
            });
        }
        catch (e) {
            logger.error(e);
            callback(e);
        }
    }
};

/*
callback: (err)
 */
module.exports.remove = function(key, callback) {
    try {
        client.del(_prefix + key, function(err) {
            if (err) {
                logger.error(err);
                if (callback) callback(err);
            }
            else {
                if (callback) callback(null);
            }
        });
    }
    catch(e) {
        logger.error(e);
        if (callback) callback(e);
    }
};

/*
prefix: the string prefix of the cache key or null to remove all CMS keys
callback: (err)
 */
module.exports.removeAll = function(startsWith, callback) {
    startsWith = _prefix + (startsWith ? startsWith : "");
    if (startsWith.substr(startsWith.length - 1, 1) !== '*')
        startsWith = startsWith + '*';

    client.keys(startsWith, function(err, rows) {
        async.each(rows, function(row, callbackDelete) {
            logger.debug('Removing data from cache: ' + row);
            client.del(row, callbackDelete)
        }, callback)
    });
};

module.exports.count = function(callback) {
    if (callback) {
        client.dbsize(function (err, size) {
            if (err) {
                logger.error(err);
                callback(err);
            }
            else
                callback(null, size);
        });
    }
};