0
0
Fork 0
mirror of https://github.com/go-gitea/gitea synced 2024-12-23 23:55:08 +01:00
gitea/modules/httpcache/httpcache.go
Yarden Shoham af0468ed8d
Set X-Gitea-Debug header once (#23361)
Instead of adding it

# Before
On the raw commit page:

![image](https://user-images.githubusercontent.com/20454870/223470744-cdf11898-e023-4198-8c8b-c294e5d78b73.png)

# After

![image](https://user-images.githubusercontent.com/20454870/223470596-af898d66-bd5b-4ddb-b220-ceb1f149bfec.png)

Fixes #23308

---------

Signed-off-by: Yarden Shoham <hrsi88@gmail.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>
2023-03-08 15:40:04 -05:00

130 lines
4.2 KiB
Go

// Copyright 2020 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package httpcache
import (
"encoding/base64"
"fmt"
"net/http"
"os"
"strconv"
"strings"
"time"
"code.gitea.io/gitea/modules/setting"
)
// SetCacheControlInHeader sets suitable cache-control headers in the response
func SetCacheControlInHeader(h http.Header, maxAge time.Duration, additionalDirectives ...string) {
directives := make([]string, 0, 2+len(additionalDirectives))
// "max-age=0 + must-revalidate" (aka "no-cache") is preferred instead of "no-store"
// because browsers may restore some input fields after navigate-back / reload a page.
if setting.IsProd {
if maxAge == 0 {
directives = append(directives, "max-age=0", "private", "must-revalidate")
} else {
directives = append(directives, "private", "max-age="+strconv.Itoa(int(maxAge.Seconds())))
}
} else {
directives = append(directives, "max-age=0", "private", "must-revalidate")
// to remind users they are using non-prod setting.
h.Set("X-Gitea-Debug", "RUN_MODE="+setting.RunMode)
}
h.Set("Cache-Control", strings.Join(append(directives, additionalDirectives...), ", "))
}
// 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) {
return HandleGenericTimeCache(req, w, fi.ModTime())
}
// HandleGenericTimeCache handles time-based caching for a HTTP request
func HandleGenericTimeCache(req *http.Request, w http.ResponseWriter, lastModified time.Time) (handled bool) {
SetCacheControlInHeader(w.Header(), setting.StaticCacheTime)
ifModifiedSince := req.Header.Get("If-Modified-Since")
if ifModifiedSince != "" {
t, err := time.Parse(http.TimeFormat, ifModifiedSince)
if err == nil && lastModified.Unix() <= t.Unix() {
w.WriteHeader(http.StatusNotModified)
return true
}
}
w.Header().Set("Last-Modified", lastModified.Format(http.TimeFormat))
return false
}
// HandleFileETagCache handles ETag-based caching for a HTTP request
func HandleFileETagCache(req *http.Request, w http.ResponseWriter, fi os.FileInfo) (handled bool) {
etag := generateETag(fi)
return HandleGenericETagCache(req, w, etag)
}
// HandleGenericETagCache handles ETag-based caching for a HTTP request.
// It returns true if the request was handled.
func HandleGenericETagCache(req *http.Request, w http.ResponseWriter, etag string) (handled bool) {
if len(etag) > 0 {
w.Header().Set("Etag", etag)
if checkIfNoneMatchIsValid(req, etag) {
w.WriteHeader(http.StatusNotModified)
return true
}
}
SetCacheControlInHeader(w.Header(), setting.StaticCacheTime)
return false
}
// checkIfNoneMatchIsValid tests if the header If-None-Match matches the ETag
func checkIfNoneMatchIsValid(req *http.Request, etag string) bool {
ifNoneMatch := req.Header.Get("If-None-Match")
if len(ifNoneMatch) > 0 {
for _, item := range strings.Split(ifNoneMatch, ",") {
item = strings.TrimSpace(item)
if item == etag {
return true
}
}
}
return false
}
// HandleGenericETagTimeCache handles ETag-based caching with Last-Modified caching for a HTTP request.
// It returns true if the request was handled.
func HandleGenericETagTimeCache(req *http.Request, w http.ResponseWriter, etag string, lastModified time.Time) (handled bool) {
if len(etag) > 0 {
w.Header().Set("Etag", etag)
}
if !lastModified.IsZero() {
w.Header().Set("Last-Modified", lastModified.Format(http.TimeFormat))
}
if len(etag) > 0 {
if checkIfNoneMatchIsValid(req, etag) {
w.WriteHeader(http.StatusNotModified)
return true
}
}
if !lastModified.IsZero() {
ifModifiedSince := req.Header.Get("If-Modified-Since")
if ifModifiedSince != "" {
t, err := time.Parse(http.TimeFormat, ifModifiedSince)
if err == nil && lastModified.Unix() <= t.Unix() {
w.WriteHeader(http.StatusNotModified)
return true
}
}
}
SetCacheControlInHeader(w.Header(), setting.StaticCacheTime)
return false
}