Heroku Redis Cloud：TypeError：无法读取未定义

Question

var cookieParser = require('cookie-parser'); 
var session = require('express-session');  
var RedisStore = require('connect-redis')(session);
app.use(cookieParser(SecretKey)); 
app.use( bodyParser.json());
app.use(bodyParser.urlencoded({extended: true}));

var redisURL = url.parse(process.env.REDISCLOUD_URL);
app.use(session({
             store: new RedisStore({ url: redisURL.hostname , port: redisURL.port, client: redis }), 
             secret: SecretKey,
             resave: true,
             saveUninitialized: true,
             key: 'sid',
             cookie: { 
                        secure: false,  
                        httpOnly: false, 
                     }  
            })
  );

//this part below is actually later down in the code so the req variable does exist
if (req.session.language) {console.log(1);}
else {console.log(0)};

这似乎是正确的，当我在本地运行redis服务器时我的代码工作但我不明白为什么它没有连接到Heroku Redis Cloud。它应该与设置代码有关。任何帮助表示赞赏！谢谢！