Add middleware to set Cache-Control header for challenge HTML (#132)

* Add middleware to set Cache-Control header for challenge HTML

* Add `NoStoreCache` middleware function in `internal/headers.go` to set Cache-Control: no-store header
* Apply `NoStoreCache` middleware in `cmd/anubis/main.go` to set Cache-Control header for challenge HTML

* docs: Add no-cache header information for challenge page

* docs: Update changelog to reflect no-store Cache-Control header addition for challenge page

* refactor: rename variable for clarity and update caching middleware in RenderIndex

* chore: move changes to the unreleased section

Signed-off-by: Jason Cameron <git@jasoncameron.dev>

---------

Signed-off-by: Jason Cameron <jasoncameron.all@gmail.com>
Signed-off-by: Jason Cameron <git@jasoncameron.dev>

1 files changed, 9 insertions, 0 deletions

diff --git a/internal/headers.go b/internal/headers.go
index a48ce54..5c6a218 100644
--- a/internal/headers.go
+++ b/internal/headers.go
@@ -64,6 +64,15 @@ func XForwardedForToXRealIP(next http.Handler) http.Handler {
 	})
 }
 
+// NoStoreCache sets the Cache-Control header to no-store for the response.
+func NoStoreCache(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Cache-Control", "no-store")
+	  next.ServeHTTP(w, r)
+	})
+}
+
+
 // Do not allow browsing directory listings in paths that end with /
 func NoBrowsing(next http.Handler) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {