move middleware out

main.go

@@ -146,10 +146,10 @@ func (s *server) HandleClear() http.HandlerFunc {
 func (s *server) routes() {
 	s.router.Handle("/public/", http.FileServer(http.FS(publicFS)))
 	s.router.HandleFunc("/", s.HandleList())
-	s.router.HandleFunc("/todo", parseForm(ensureMethod("POST", s.HandleCreate())))
-	s.router.HandleFunc("/toggle", parseForm(ensureMethod("POST", s.HandleToggle())))
-	s.router.HandleFunc("/destroy", parseForm(ensureMethod("POST", s.HandleDestroy())))
-	s.router.HandleFunc("/clear", ensureMethod("POST", s.HandleClear()))
+	s.router.HandleFunc("/todo", WithForm(WithMethod("POST", s.HandleCreate())))
+	s.router.HandleFunc("/toggle", WithForm(WithMethod("POST", s.HandleToggle())))
+	s.router.HandleFunc("/destroy", WithForm(WithMethod("POST", s.HandleDestroy())))
+	s.router.HandleFunc("/clear", WithMethod("POST", s.HandleClear()))
 }
 
 func run() error {
@@ -162,25 +162,3 @@ func run() error {
 func main() {
 	log.Fatal(run())
 }
-
-func ensureMethod(method string, next http.Handler) http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request) {
-		if r.Method != method {
-			w.WriteHeader(http.StatusMethodNotAllowed)
-			return
-		}
-		next.ServeHTTP(w, r)
-	}
-}
-
-func parseForm(next http.Handler) http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request) {
-		if err := r.ParseForm(); err != nil {
-			w.WriteHeader(http.StatusBadRequest)
-			w.Write([]byte("Bad Request"))
-			return
-		}
-
-		next.ServeHTTP(w, r)
-	}
-}

middleware.go

@@ -0,0 +1,25 @@
+package main
+
+import "net/http"
+
+func WithMethod(method string, next http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != method {
+			w.WriteHeader(http.StatusMethodNotAllowed)
+			return
+		}
+		next.ServeHTTP(w, r)
+	}
+}
+
+func WithForm(next http.Handler) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if err := r.ParseForm(); err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			w.Write([]byte("Bad Request"))
+			return
+		}
+
+		next.ServeHTTP(w, r)
+	}
+}