owncast/router/middleware/caching.go
2020-11-12 15:14:59 -08:00

46 lines
1.2 KiB
Go

package middleware
import (
"net/http"
"os"
"path/filepath"
"strconv"
"github.com/amalfra/etag"
"github.com/owncast/owncast/utils"
)
// DisableCache writes the disable cache header on the responses.
func DisableCache(w http.ResponseWriter) {
w.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
w.Header().Set("Expires", "Thu, 1 Jan 1970 00:00:00 GMT")
}
func setCacheSeconds(seconds int, w http.ResponseWriter) {
secondsStr := strconv.Itoa(seconds)
w.Header().Set("Cache-Control", "public, max-age="+secondsStr)
}
// ProcessEtags gets and sets ETags for caching purposes.
func ProcessEtags(w http.ResponseWriter, r *http.Request) int {
info, err := os.Stat(filepath.Join("webroot", r.URL.Path))
if err != nil {
return 0
}
localContentEtag := etag.Generate(info.ModTime().String(), true)
if remoteEtagHeader := r.Header.Get("If-None-Match"); remoteEtagHeader != "" {
if remoteEtagHeader == localContentEtag {
return http.StatusNotModified
}
}
w.Header().Set("Etag", localContentEtag)
return 0
}
// SetCachingHeaders will set the cache control header of a response.
func SetCachingHeaders(w http.ResponseWriter, r *http.Request) {
setCacheSeconds(utils.GetCacheDurationSecondsForPath(r.URL.Path), w)
}