internal/shared/middleware/security_headers.go

// internal/shared/middleware/security_headers.go
package middleware

import "net/http"

func SecurityHeaders(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

		w.Header().Set("X-Frame-Options", "DENY")
		w.Header().Set("X-Content-Type-Options", "nosniff")
		w.Header().Set("Referrer-Policy", "strict-origin-when-cross-origin")
		w.Header().Set("Strict-Transport-Security", "max-age=63072000; includeSubDomains")
		w.Header().Set("Content-Security-Policy", "default-src 'self'")

		next.ServeHTTP(w, r)
	})
}