Improved readability of HSTS header construction logic
Currently, the logic for constructing the value of the Strict-Transport-Security (HSTS) header is to nest fmt.Sprintf and concatenate the strings.
I believe that rewriting this part by adding each directive (max-age, includeSubdomains, preload) to the slice and finally joining them with strings.Join will make the logic clearer and improve readability.
Add comment regarding X-XSS-Protection header
The X-XSS-Protection header is deprecated in many modern browsers, and the Content-Security-Policy (CSP) header is recommended.
While this header is important for backward compatibility, I believe that supplementing this background with comments will help users of this middleware choose more appropriate security settings.
Improved readability of HSTS header construction logic
Currently, the logic for constructing the value of the Strict-Transport-Security (HSTS) header is to nest fmt.Sprintf and concatenate the strings.
I believe that rewriting this part by adding each directive (max-age, includeSubdomains, preload) to the slice and finally joining them with strings.Join will make the logic clearer and improve readability.
Add comment regarding X-XSS-Protection header
The X-XSS-Protection header is deprecated in many modern browsers, and the Content-Security-Policy (CSP) header is recommended.
While this header is important for backward compatibility, I believe that supplementing this background with comments will help users of this middleware choose more appropriate security settings.