forgejo/modules/public/public.go
KN4CK3R a35a5b225c
Add ETag header (#15370)
* Add ETag header.

* Comply with RFC 7232.

* Moved logic into httpcache.go

* Changed name.

* Lint

* Implemented If-None-Match list.

* Fixed missing header on *

* Removed weak etag support.

* Removed * support.

* Added unit test.

* Lint

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
2021-04-12 10:49:26 -04:00

175 lines
4 KiB
Go

// Copyright 2016 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 public
import (
"log"
"net/http"
"path"
"path/filepath"
"strings"
"code.gitea.io/gitea/modules/httpcache"
"code.gitea.io/gitea/modules/setting"
)
// Options represents the available options to configure the handler.
type Options struct {
Directory string
IndexFile string
SkipLogging bool
FileSystem http.FileSystem
Prefix string
}
// KnownPublicEntries list all direct children in the `public` directory
var KnownPublicEntries = []string{
"css",
"fonts",
"img",
"js",
"serviceworker.js",
"vendor",
"favicon.ico",
}
// Custom implements the static handler for serving custom assets.
func Custom(opts *Options) func(next http.Handler) http.Handler {
return opts.staticHandler(path.Join(setting.CustomPath, "public"))
}
// staticFileSystem implements http.FileSystem interface.
type staticFileSystem struct {
dir *http.Dir
}
func newStaticFileSystem(directory string) staticFileSystem {
if !filepath.IsAbs(directory) {
directory = filepath.Join(setting.AppWorkPath, directory)
}
dir := http.Dir(directory)
return staticFileSystem{&dir}
}
func (fs staticFileSystem) Open(name string) (http.File, error) {
return fs.dir.Open(name)
}
// StaticHandler sets up a new middleware for serving static files in the
func StaticHandler(dir string, opts *Options) func(next http.Handler) http.Handler {
return opts.staticHandler(dir)
}
func (opts *Options) staticHandler(dir string) func(next http.Handler) http.Handler {
return func(next http.Handler) http.Handler {
// Defaults
if len(opts.IndexFile) == 0 {
opts.IndexFile = "index.html"
}
// Normalize the prefix if provided
if opts.Prefix != "" {
// Ensure we have a leading '/'
if opts.Prefix[0] != '/' {
opts.Prefix = "/" + opts.Prefix
}
// Remove any trailing '/'
opts.Prefix = strings.TrimRight(opts.Prefix, "/")
}
if opts.FileSystem == nil {
opts.FileSystem = newStaticFileSystem(dir)
}
return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
if !opts.handle(w, req, opts) {
next.ServeHTTP(w, req)
}
})
}
}
// parseAcceptEncoding parse Accept-Encoding: deflate, gzip;q=1.0, *;q=0.5 as compress methods
func parseAcceptEncoding(val string) map[string]bool {
parts := strings.Split(val, ";")
var types = make(map[string]bool)
for _, v := range strings.Split(parts[0], ",") {
types[strings.TrimSpace(v)] = true
}
return types
}
func (opts *Options) handle(w http.ResponseWriter, req *http.Request, opt *Options) bool {
if req.Method != "GET" && req.Method != "HEAD" {
return false
}
file := req.URL.Path
// if we have a prefix, filter requests by stripping the prefix
if opt.Prefix != "" {
if !strings.HasPrefix(file, opt.Prefix) {
return false
}
file = file[len(opt.Prefix):]
if file != "" && file[0] != '/' {
return false
}
}
f, err := opt.FileSystem.Open(file)
if err != nil {
// 404 requests to any known entries in `public`
if path.Base(opts.Directory) == "public" {
parts := strings.Split(file, "/")
if len(parts) < 2 {
return false
}
for _, entry := range KnownPublicEntries {
if entry == parts[1] {
w.WriteHeader(404)
return true
}
}
}
return false
}
defer f.Close()
fi, err := f.Stat()
if err != nil {
log.Printf("[Static] %q exists, but fails to open: %v", file, err)
return true
}
// Try to serve index file
if fi.IsDir() {
// Redirect if missing trailing slash.
if !strings.HasSuffix(req.URL.Path, "/") {
http.Redirect(w, req, path.Clean(req.URL.Path+"/"), http.StatusFound)
return true
}
f, err = opt.FileSystem.Open(file)
if err != nil {
return false // Discard error.
}
defer f.Close()
fi, err = f.Stat()
if err != nil || fi.IsDir() {
return false
}
}
if !opt.SkipLogging {
log.Println("[Static] Serving " + file)
}
if httpcache.HandleFileETagCache(req, w, fi) {
return true
}
ServeContent(w, req, fi, fi.ModTime(), f)
return true
}