Search code examples
gobrowser-cachestatic-files

Leverage browser caching for the static files


I am not sure, how in Golang we can leverage browser caching for only static files like CSS, js and not HTML template file.

With .htaccess in Apache, it used to be easy, but I don't see any such thing in golang

I want to know, any hack or method available where I can cache static files like css, js

without using cloudflare - My app does not work with cloudflare.


Solution

  • Browser caching is controlled by headers sent by the server. This way it doesn’t depend on particular installed software.

    You need to send headers Etag and Cache-Control. Like this

    func Handler(w http.ResponseWriter, r *http.Request) {
        e := "SomeKey describing content - eg checksum"
        w.Header().Set("Etag", e)
        w.Header().Set("Cache-Control", "max-age=2592000") // 30 days
    
        if match := r.Header.Get("If-None-Match"); match != "" {
            if strings.Contains(match, e) {
                w.WriteHeader(http.StatusNotModified)
                return
            }
        }
        ...
    }
    

    Useful links: