Go error: Cannot use argument (type []string) as type string in argument

Question

Trying to get acquainted with go. I want to do something like this:

func validation(){
    headers := metadata.New(map[string]string{"auth":"", "abc": "", "xyz" : ""})
    token := headers["auth"]

    data.Add("cookie", token)
}

I am getting the following error : cannot use token (type []string) as type string in argument to data.Add. Has this error got to do anything with the metadata(map) I have inside the function?

Answer 1

Token is a []string and the 2nd argument to Add is a string. Assuming that you want the first element of the slice and the slice is guaranteed to have at least one element, use this:

data.Add("cookie", token[0])

If you don't know that there's at least one element in the slice, then protect with an if:

if len(token) > 0 {
   data.Add("cookie", token[0])
} else {
   // handle missing value
}