Need help for the below problem.

How to use loop function to find the number of 'Null' values in each column for a data frame.

Thanks 

Example: `df<-data.frame(name=c("Patrik","Tom","Harry","Bose"),
 Age=c(45,NA,54,34),
 Location=c("NA","CA",NA,"IR"))`
['https://Stackoverflow.com/questions/57924568', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/10045435/']
Ok, regarding your second code snippet there are several things that I noticed.

You are using the cookie-parser package that you affected to the cookieParser variable but after you use `Cookies.get` but I don't see where `Cookies` is coming from? so maybe what you want to do is `cookieParser.get` but by checking the cookie-parser package I didn't see any `get` method so it's hard to help you here.

Other than that you should be able to see your cookies by using `req.cookies` inside your function.

I hope it will help you a bit...
Let me say you that if you want to store a JWT into a cookie and other extra information it could be stored or not depending on the size of your cookie.

For more information about max size for cookies check this: <https://www.quora.com/What-Is-The-Maximum-Size-Of-Cookie-In-A-Web-Browser>

On another hand, I saw a problem in your implementation that I recommend you the below:

If you are receiving a JWT, you would keep the nature of a JWT authenticator.

<https://medium.com/@siddharthac6/json-web-token-jwt-the-right-way-of-implementing-with-node-js-65b8915d550e>