rediscache.js

module.exports = function(Model, options) {
  var redis = require("redis")
  var client = null

  if (options.client) {
      var clientSettings = options.client;
      client = redis.createClient(clientSettings);
  } else {
      var app = require('../../server/server.js');
      if (app.redisClient) {
          client = app.redisClient
      } else {
          client = redis.createClient(app.get('redis'));
      }
  }

  var redisDeletePattern = require('redis-delete-pattern');

  client.on("error", function (err) {
      console.log(err);
      // try to connect again with server config
      if(err.toString().indexOf("invalid password") !== -1){
          console.log("Invalid password... reconnecting with server config...");
          var app = require('../../server/server');
          var clientSettings = app.get('redis');
          client = redis.createClient(clientSettings);
      }
  });


  Model.beforeRemote('**', function(ctx, res, next) {
      // get all find methods and search first in cache
      if((ctx.method.name.indexOf("find") !== -1 || ctx.method.name.indexOf("__get") !== -1 || ctx.method.name.indexOf("get") !== -1) && client.connected){
          if(typeof ctx.req.query.cache != 'undefined'){
              var modelName = ctx.method.sharedClass.name + "_" + ctx.method.name;
              var cachExpire = ctx.req.query.cache;

              // set key name
              var cache_key = modelName+'_'+new Buffer(JSON.stringify(ctx.req.params) + JSON.stringify(ctx.req.query)).toString('base64');

              // search for cache
              client.get(cache_key, function(err, val) {
                  if(err){
                      console.log(err);
                  }

                  if(val !== null){
                      ctx.result = JSON.parse(val);
                      ctx.res.setHeader('Cache-Hit', true)
                      client.ttl(cache_key, function(err, data) {
                        if (!err) {
                          ctx.res.setHeader('Cache-TTL', data)
                          var expires = new Date()
                          expires.setSeconds(expires.getSeconds() + parseInt(data))
                          ctx.res.setHeader('Expires', expires)
                        }
                        ctx.done(function (err) {
                          if (err) return next(err);
                        });
                      })
                  }else{
                      //return data
                      ctx.res.setHeader('Cache-Hit', false)
                      ctx.res.setHeader('Cache-TTL', cachExpire)
                      var expires = new Date()
                      expires.setSeconds(expires.getSeconds() + parseInt(cachExpire))
                      ctx.res.setHeader('Expires', expires)
                      next();
                  }
              });

          }else{
              next();
          }
      }else{
          next();
      }
  });

  Model.afterRemote('**', function(ctx, res, next) {
      // get all find methods and search first in cache - if not exist save in cache
      if((ctx.method.name.indexOf("find") !== -1 || ctx.method.name.indexOf("__get") !== -1 || ctx.method.name.indexOf("get") !== -1) && client.connected){
          if(typeof ctx.req.query.cache != 'undefined'){
              var modelName = ctx.method.sharedClass.name + "_" + ctx.method.name;
              var cachExpire = ctx.req.query.cache;

              // set key name
              var cache_key = modelName+'_'+new Buffer(JSON.stringify(ctx.req.params) + JSON.stringify(ctx.req.query)).toString('base64');
              // search for cache
              client.get(cache_key, function(err, val) {
                  if(err){
                      console.log(err);
                  }

                  if(val == null){
                      // set cache key
                      client.set(cache_key, JSON.stringify(res));
                      client.expire(cache_key, cachExpire);
                      next();
                  }else{
                      next();
                  }
              });

          }else{
              next();
          }
      }else{
          next();
      }
  });

  Model.afterRemote('**', function(ctx, res, next) {
      // delete cache on patchOrCreate, create, delete, update, destroy, upsert
      if((ctx.method.name.indexOf("find") == -1 && ctx.method.name.indexOf("__get") == -1) && client.connected){
          var modelName = ctx.method.sharedClass.name + "_" + ctx.method.name;
          var cachExpire = ctx.req.query.cache;

          // set key name
          var cache_key = modelName+'_*';

          // delete cache
          redisDeletePattern({
              redis: client,
              pattern: cache_key
          }, function handleError (err) {
              if(err){
                  console.log(err);
              }
              next();
          });

      }else{
          next();
      }
  });
}