cloudcms-server/middleware/cache/providers/redis.js

Cloud CMS Application Server Module

var redisClientFactory = require("../../../clients/redis");
const redisHelper = require("../../../util/redis");

/**
 * Redis distributed cache.
 *
 * @type {*}
 */
exports = module.exports = function(cacheConfig)
{
    var client = null;
    
    var logger = redisHelper.redisLogger("REDIS_CACHE", "CLOUDCMS_CACHE_", "error")

    var r = {};

    r.init = function(callback)
    {
        redisClientFactory.create(cacheConfig, function(err, _client) {
    
            if (err) {
                return callback(err);
            }
    
            client = _client;
    
            return callback();
    
        });
    };

    r.write = function(key, value, seconds, callback)
    {
        logger.info('write, key = ' + key + ', value = ' + value + ', seconds = ' + seconds + ', typeofval: ' + typeof(value));
        (async function() {
    
            var reply = null;
            var err = null;
    
            try
            {
                var config = {};
                if (seconds >= 0) {
                    config["EX"] = seconds;
                }
                
                reply = await client.set(key, JSON.stringify(value), config);
            }
            catch (e)
            {
                err = e;
            }
    
            if (reply) {
                logger.info("write -> reply = " + reply);
            }
    
            if (err) {
                logger.error("write error. key: " + key + " value: " + JSON.stringify(value) + ". error:" + err + ", value type: " + typeof(value));
            }
    
            callback(err, reply);
            
        })();
    };

    r.read = function(key, callback)
    {
        logger.info('read, key = ' + key);

        (async function() {
    
            var err = null;
            var reply = null;
    
            try
            {
                reply = await client.get(key);
            }
            catch (e)
            {
                err = e;
            }
    
            if (err) {
                logger.error("read error. key: " + key + ". error: " + err);
            }
    
            if (reply) {
                logger.info("read. key: " + key + " -> reply = " + reply);
            }
    
            var result = null;
            try
            {
                result = JSON.parse(reply);
            }
            catch (ex)
            {
                result = null;
                err = ex;
        
                if (err)
                {
                    logger.error("error parsing reply. key: " + key + ". error:" + err);
                }
            }
    
            callback(err, result);
        })();
    };

    r.remove = function(key, callback)
    {
        logger.info('remove, key = ' + key);
    
        (async function() {
    
            var err = null;
            
            try
            {
                await client.del(key);
                logger.info("remove. key: " + key);
            }
            catch (e)
            {
                err = e;
            }
    
            if (err) {
                logger.error("del error. key: " + key + ". error: " + err);
            }
    
            callback(err);
        })();
    };
    
    r.keys = function(prefix, callback)
    {
        logger.info('keys, prefix = ' + prefix);
        
        (async function() {
    
            var err = null;
            var reply = null;
    
            try
            {
                reply = await client.keys(prefix + '*');
            }
            catch (e)
            {
                err = e;
            }
    
            if (err) {
                logger.error("error reading keys for prefix: " + prefix + ". error:" + err);
            }
    
            if (reply) {
                logger.info("keys -> reply = " + reply);
            }
    
            callback(err, reply);
            
        })();
    };

    return r;
};