appview/middleware: indiscriminately try to refresh the session

previously, we would only refresh sessions when authenticated requests
took place. the new middleware attempts a refresh for every request, if
expiry is approaching (<5m). this way, user sessions remain refreshing
by simply hanging out on tangled.

Signed-off-by: oppiliappan <[e-mail]>

appview/middleware/middleware.go

···
 
 type middlewareFunc func(http.Handler) http.Handler
 
+func (mw *Middleware) TryRefreshSession() middlewareFunc {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			_, auth, err := mw.oauth.GetSession(r)
+			if err != nil {
+				log.Println("could not refresh session", "err", err, "auth", auth)
+			}
+
+			next.ServeHTTP(w, r)
+		})
+	}
+}
+
 func AuthMiddleware(a *oauth.OAuth) middlewareFunc {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {

appview/state/router.go

···
 		s.pages,
 	)
 
+	router.Use(middleware.TryRefreshSession())
 	router.Get("/favicon.svg", s.Favicon)
 	router.Get("/favicon.ico", s.Favicon)