60 lines
1.7 KiB
Go
60 lines
1.7 KiB
Go
// Copyright 2020 The Gitea Authors. All rights reserved.
|
|
// Use of this source code is governed by a MIT-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package httpcache
|
|
|
|
import (
|
|
"encoding/base64"
|
|
"fmt"
|
|
"net/http"
|
|
"os"
|
|
"strconv"
|
|
"time"
|
|
|
|
"code.gitea.io/gitea/modules/setting"
|
|
)
|
|
|
|
// GetCacheControl returns a suitable "Cache-Control" header value
|
|
func GetCacheControl() string {
|
|
if !setting.IsProd() {
|
|
return "no-store"
|
|
}
|
|
return "private, max-age=" + strconv.FormatInt(int64(setting.StaticCacheTime.Seconds()), 10)
|
|
}
|
|
|
|
// generateETag generates an ETag based on size, filename and file modification time
|
|
func generateETag(fi os.FileInfo) string {
|
|
etag := fmt.Sprint(fi.Size()) + fi.Name() + fi.ModTime().UTC().Format(http.TimeFormat)
|
|
return base64.StdEncoding.EncodeToString([]byte(etag))
|
|
}
|
|
|
|
// HandleTimeCache handles time-based caching for a HTTP request
|
|
func HandleTimeCache(req *http.Request, w http.ResponseWriter, fi os.FileInfo) (handled bool) {
|
|
ifModifiedSince := req.Header.Get("If-Modified-Since")
|
|
if ifModifiedSince != "" {
|
|
t, err := time.Parse(http.TimeFormat, ifModifiedSince)
|
|
if err == nil && fi.ModTime().Unix() <= t.Unix() {
|
|
w.WriteHeader(http.StatusNotModified)
|
|
return true
|
|
}
|
|
}
|
|
|
|
w.Header().Set("Cache-Control", GetCacheControl())
|
|
w.Header().Set("Last-Modified", fi.ModTime().Format(http.TimeFormat))
|
|
return false
|
|
}
|
|
|
|
// HandleEtagCache handles ETag-based caching for a HTTP request
|
|
func HandleEtagCache(req *http.Request, w http.ResponseWriter, fi os.FileInfo) (handled bool) {
|
|
etag := generateETag(fi)
|
|
if req.Header.Get("If-None-Match") == etag {
|
|
w.WriteHeader(http.StatusNotModified)
|
|
return true
|
|
}
|
|
|
|
w.Header().Set("Cache-Control", GetCacheControl())
|
|
w.Header().Set("ETag", etag)
|
|
return false
|
|
}
|