anubis/internal/headers.go
2025-03-21 16:45:33 -04:00

50 lines
1.4 KiB
Go

package internal
import (
"log/slog"
"net/http"
"github.com/TecharoHQ/anubis"
"github.com/sebest/xff"
)
// UnchangingCache sets the Cache-Control header to cache a response for 1 year if
// and only if the application is compiled in "release" mode by Docker.
func UnchangingCache(next http.Handler) http.Handler {
if anubis.Version == "devel" {
return next
}
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Cache-Control", "public, max-age=31536000")
next.ServeHTTP(w, r)
})
}
// DefaultXRealIP sets the X-Real-Ip header to the given value if and only if
// it is not an empty string.
func DefaultXRealIP(defaultIP string, next http.Handler) http.Handler {
if defaultIP == "" {
slog.Debug("skipping middleware, defaultIP is empty")
return next
}
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
r.Header.Set("X-Real-Ip", defaultIP)
next.ServeHTTP(w, r)
})
}
// XForwardedForToXRealIP sets the X-Real-Ip header based on the contents
// of the X-Forwarded-For header.
func XForwardedForToXRealIP(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if xffHeader := r.Header.Get("X-Forwarded-For"); r.Header.Get("X-Real-Ip") == "" && xffHeader != "" {
ip := xff.Parse(xffHeader)
slog.Debug("setting x-real-ip", "val", ip)
r.Header.Set("X-Real-Ip", ip)
}
next.ServeHTTP(w, r)
})
}