add

diff --git a/web/Web.go b/web/Web.go
index ff168a2871c587d1b69a3767c5885840e6b5a531..65c4c7120d8892214b9f068284c98ed4fd06b091 100644 (file)
--- a/web/Web.go
+++ b/web/Web.go
@@ -10,6 +10,7 @@ import (
        "sync/atomic"
        "time"
 
+       "github.com/dustin/go-humanize"
        psync "github.com/qydysky/part/sync"
        sys "github.com/qydysky/part/sys"
 )
@@ -229,10 +230,50 @@ type Cache struct {
        gcL atomic.Int64
 }
 
+type cacheRes struct {
+       headerf      func() http.Header
+       writef       func([]byte) (int, error)
+       writeHeaderf func(statusCode int)
+}
+
+func (t cacheRes) Header() http.Header {
+       return t.headerf()
+}
+func (t cacheRes) Write(b []byte) (int, error) {
+       return t.writef(b)
+}
+func (t cacheRes) WriteHeader(statusCode int) {
+       t.writeHeaderf(statusCode)
+}
+
 func (t *Cache) IsCache(key string) (res *[]byte, isCache bool) {
        return t.g.Load(key)
 }
 
+func (t *Cache) Cache(key string, aliveDur time.Duration, w http.ResponseWriter) http.ResponseWriter {
+       var (
+               res    cacheRes
+               called atomic.Bool
+       )
+       res.headerf = w.Header
+       res.writeHeaderf = w.WriteHeader
+       res.writef = func(b []byte) (int, error) {
+               if called.CompareAndSwap(false, true) {
+                       if len(b) < humanize.MByte {
+                               t.g.Store(key, &b, aliveDur)
+                       }
+               } else {
+                       panic("Cache Write called")
+               }
+               return w.Write(b)
+       }
+       if s := int64(t.g.Len()); s > 10 && t.gcL.Load() <= s {
+               t.gcL.Store(s * 2)
+               t.g.GC()
+       }
+       return res
+}
+
 func (t *Cache) Store(key string, aliveDur time.Duration, data *[]byte) {
        t.g.Store(key, data, aliveDur)
        if s := int64(t.g.Len()); s > 10 && t.gcL.Load() <= s {