From c93a0bfe60a775065565214a2564649a2642a790 Mon Sep 17 00:00:00 2001
From: qydysky <qydysky@foxmail.com>
Date: Sun, 21 Jul 2024 20:05:12 +0800
Subject: [PATCH] web.NotModified

---
 web/Web.go      | 20 ++++++++++++++++++++
 web/Web_test.go | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)

diff --git a/web/Web.go b/web/Web.go
index 1f5f8e2..2dd1fc8 100644
--- a/web/Web.go
+++ b/web/Web.go
@@ -692,6 +692,26 @@ func IsMethod(r *http.Request, method ...string) bool {
 	return false
 }
 
+func NotModified(r *http.Request, w http.ResponseWriter, cuTime time.Time) (notMod bool) {
+	modTimeS := cuTime.Format(time.RFC1123)
+
+	w.Header().Add(`Cache-Control`, `private`)
+	w.Header().Add(`ETag`, modTimeS)
+	w.Header().Add(`Last-Modified`, modTimeS)
+
+	if inm := r.Header.Get(`If-None-Match`); inm == modTimeS {
+		w.WriteHeader(http.StatusNotModified)
+		return true
+	}
+	if ims := r.Header.Get(`If-Modified-Since`); ims != "" {
+		if mod, e := time.Parse(time.RFC1123, ims); e == nil && mod.Equal(cuTime) {
+			w.WriteHeader(http.StatusNotModified)
+			return true
+		}
+	}
+	return false
+}
+
 func Easy_boot() *Web {
 	s := New(&http.Server{
 		Addr:         "127.0.0.1:" + strconv.Itoa(sys.Sys().GetFreePort()),
diff --git a/web/Web_test.go b/web/Web_test.go
index 3bc1b2a..a4eb4b3 100644
--- a/web/Web_test.go
+++ b/web/Web_test.go
@@ -40,6 +40,52 @@ func Test_Exprier(t *testing.T) {
 	}
 }
 
+func Test_Mod(t *testing.T) {
+	s := New(&http.Server{
+		Addr:         "0.0.0.0:13000",
+		WriteTimeout: time.Second * time.Duration(10),
+	})
+	defer s.Shutdown()
+	s.Handle(map[string]func(http.ResponseWriter, *http.Request){
+		`/mod`: func(w http.ResponseWriter, r *http.Request) {
+			cu, _ := time.Parse(time.RFC1123, `Tue, 22 Feb 2022 22:00:00 GMT`)
+			if NotModified(r, w, cu) {
+				return
+			}
+			w.Write([]byte("abc强强强强"))
+		},
+		`/`: func(w http.ResponseWriter, r *http.Request) {
+			cu, _ := time.Parse(time.RFC1123, `Tue, 22 Feb 2022 22:00:00 GMT`)
+			if NotModified(r, w, cu) {
+				return
+			}
+			w.Write([]byte(""))
+		},
+	})
+
+	time.Sleep(time.Second)
+
+	r := reqf.New()
+	{
+		r.Reqf(reqf.Rval{
+			Url: "http://127.0.0.1:13000/mod",
+		})
+		if !bytes.Equal(r.Respon, []byte("abc强强强强")) {
+			t.Fatal(r.Respon)
+		}
+		r.Reqf(reqf.Rval{
+			Url: "http://127.0.0.1:13000/mod",
+			Header: map[string]string{
+				`If-None-Match`: r.Response.Header.Get(`ETag`),
+			},
+		})
+		if r.Response.StatusCode != http.StatusNotModified {
+			t.Fatal(r.Respon)
+		}
+	}
+	time.Sleep(time.Second*10)
+}
+
 func Test_Server(t *testing.T) {
 	s := New(&http.Server{
 		Addr:         "127.0.0.1:13000",
-- 
2.39.2