/* Copyright © 2023 Seednode */ package cmd import ( "encoding/gob" "encoding/json" "errors" "fmt" "io" "log" "math/rand" "net/http" "net/url" "os" "path/filepath" "regexp" "runtime" "sort" "strconv" "strings" "sync" "time" "github.com/klauspost/compress/zstd" "github.com/yosssi/gohtml" ) var ( ErrIndexNotExist = errors.New(`specified index does not exist`) ) const ( LogDate string = `2006-01-02T15:04:05.000-07:00` Prefix string = `/src` RedirectStatusCode int = http.StatusSeeOther ) type Regexes struct { alphanumeric *regexp.Regexp filename *regexp.Regexp units *regexp.Regexp } type Filters struct { includes []string excludes []string } func (f *Filters) IsEmpty() bool { return !(f.HasIncludes() || f.HasExcludes()) } func (f *Filters) HasIncludes() bool { return len(f.includes) != 0 } func (f *Filters) Includes() string { return strings.Join(f.includes, ",") } func (f *Filters) HasExcludes() bool { return len(f.excludes) != 0 } func (f *Filters) Excludes() string { return strings.Join(f.excludes, ",") } type Index struct { mutex sync.RWMutex list []string } func (i *Index) Index() []string { i.mutex.RLock() val := i.list i.mutex.RUnlock() return val } func (i *Index) setIndex(val []string) { i.mutex.Lock() i.list = val i.mutex.Unlock() } func (i *Index) generateCache(args []string) { i.mutex.Lock() i.list = []string{} i.mutex.Unlock() fileList(args, &Filters{}, "", i) if cache && cacheFile != "" { i.Export(cacheFile) } } func (i *Index) IsEmpty() bool { i.mutex.RLock() length := len(i.list) i.mutex.RUnlock() return length == 0 } func (i *Index) Export(path string) error { file, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0600) if err != nil { return err } defer file.Close() z, err := zstd.NewWriter(file) if err != nil { return err } defer z.Close() enc := gob.NewEncoder(z) enc.Encode(&i.list) return nil } func (i *Index) Import(path string) error { file, err := os.OpenFile(path, os.O_RDONLY, 0600) if os.IsNotExist(err) { return ErrIndexNotExist } else if err != nil { return err } defer file.Close() z, err := zstd.NewReader(file) if err != nil { return err } defer z.Close() dec := gob.NewDecoder(z) err = dec.Decode(&i.list) if err != nil { return err } return nil } type ServeStats struct { mutex sync.RWMutex list []string count map[string]uint64 size map[string]string times map[string][]string } func (s *ServeStats) incrementCounter(image string, timestamp time.Time, filesize string) { s.mutex.Lock() s.count[image]++ s.times[image] = append(s.times[image], timestamp.Format(LogDate)) _, exists := s.size[image] if !exists { s.size[image] = filesize } if !contains(s.list, image) { s.list = append(s.list, image) } s.mutex.Unlock() } func (s *ServeStats) ListImages() ([]byte, error) { s.mutex.RLock() sortedList := &ServeStats{ mutex: sync.RWMutex{}, list: s.list, count: s.count, size: s.size, times: s.times, } s.mutex.RUnlock() sort.SliceStable(sortedList.list, func(p, q int) bool { return sortedList.list[p] < sortedList.list[q] }) a := []timesServed{} for _, image := range sortedList.list { a = append(a, timesServed{image, sortedList.count[image], sortedList.size[image], sortedList.times[image]}) } r, err := json.MarshalIndent(a, "", " ") if err != nil { return []byte{}, err } return r, nil } type timesServed struct { File string Served uint64 Size string Times []string } func notFound(w http.ResponseWriter, r *http.Request, filePath string) error { startTime := time.Now() if verbose { fmt.Printf("%s | Unavailable file %s requested by %s\n", startTime.Format(LogDate), filePath, r.RemoteAddr, ) } w.WriteHeader(404) w.Header().Add("Content-Type", "text/html") var htmlBody strings.Builder htmlBody.WriteString(``) htmlBody.WriteString(``) htmlBody.WriteString(`Not Found`) htmlBody.WriteString(`404 page not found`) _, err := io.WriteString(w, gohtml.Format(htmlBody.String())) if err != nil { return err } return nil } func refreshInterval(r *http.Request, Regexes *Regexes) (int64, string) { refreshInterval := r.URL.Query().Get("refresh") if !Regexes.units.MatchString(refreshInterval) { return 0, "0ms" } duration, err := time.ParseDuration(refreshInterval) if err != nil { return 0, "0ms" } durationInMs := duration.Milliseconds() return durationInMs, refreshInterval } func sortOrder(r *http.Request) string { sortOrder := r.URL.Query().Get("sort") if sortOrder == "asc" || sortOrder == "desc" { return sortOrder } return "" } func splitQueryParams(query string, Regexes *Regexes) []string { results := []string{} if query == "" { return results } params := strings.Split(query, ",") for i := 0; i < len(params); i++ { if Regexes.alphanumeric.MatchString(params[i]) { results = append(results, strings.ToLower(params[i])) } } return results } func generateQueryParams(filters *Filters, sortOrder, refreshInterval string) string { var hasParams bool var queryParams strings.Builder queryParams.WriteString("?") if filtering { queryParams.WriteString("include=") if filters.HasIncludes() { queryParams.WriteString(filters.Includes()) } queryParams.WriteString("&exclude=") if filters.HasExcludes() { queryParams.WriteString(filters.Excludes()) } hasParams = true } if sorting { if hasParams { queryParams.WriteString("&") } queryParams.WriteString(fmt.Sprintf("sort=%s", sortOrder)) hasParams = true } if hasParams { queryParams.WriteString("&") } queryParams.WriteString(fmt.Sprintf("refresh=%s", refreshInterval)) return queryParams.String() } func stripQueryParams(u string) (string, error) { uri, err := url.Parse(u) if err != nil { return "", err } uri.RawQuery = "" escapedUri, err := url.QueryUnescape(uri.String()) if err != nil { return "", err } if runtime.GOOS == "windows" { return strings.TrimPrefix(escapedUri, "/"), nil } return escapedUri, nil } func generateFilePath(filePath string) string { var htmlBody strings.Builder htmlBody.WriteString(Prefix) if runtime.GOOS == "windows" { htmlBody.WriteString(`/`) } htmlBody.WriteString(filePath) return htmlBody.String() } func refererToUri(referer string) string { parts := strings.SplitAfterN(referer, "/", 4) if len(parts) < 4 { return "" } return "/" + parts[3] } func realIP(r *http.Request) string { remoteAddr := strings.SplitAfter(r.RemoteAddr, ":") if len(remoteAddr) < 1 { return r.RemoteAddr } remotePort := remoteAddr[len(remoteAddr)-1] cfIP := r.Header.Get("Cf-Connecting-Ip") xRealIp := r.Header.Get("X-Real-Ip") switch { case cfIP != "": return cfIP + ":" + remotePort case xRealIp != "": return xRealIp + ":" + remotePort default: return r.RemoteAddr } } func serveHtml(w http.ResponseWriter, r *http.Request, filePath string, dimensions *Dimensions, filters *Filters, Regexes *Regexes) error { fileName := filepath.Base(filePath) w.Header().Add("Content-Type", "text/html") sortOrder := sortOrder(r) refreshTimer, refreshInterval := refreshInterval(r, Regexes) queryParams := generateQueryParams(filters, sortOrder, refreshInterval) var htmlBody strings.Builder htmlBody.WriteString(``) htmlBody.WriteString(``) htmlBody.WriteString(fmt.Sprintf(`%s (%dx%d)`, fileName, dimensions.width, dimensions.height)) htmlBody.WriteString(``) if refreshInterval != "0ms" { htmlBody.WriteString(fmt.Sprintf("", queryParams, refreshTimer)) } htmlBody.WriteString(fmt.Sprintf(`Roulette selected: %s`, queryParams, generateFilePath(filePath), dimensions.width, dimensions.height, fileName)) htmlBody.WriteString(``) _, err := io.WriteString(w, gohtml.Format(htmlBody.String())) if err != nil { return err } return nil } func serveStaticFile(w http.ResponseWriter, r *http.Request, paths []string, stats *ServeStats) error { prefixedFilePath, err := stripQueryParams(r.URL.Path) if err != nil { return err } filePath, err := filepath.EvalSymlinks(strings.TrimPrefix(prefixedFilePath, Prefix)) if err != nil { return err } if !pathIsValid(filePath, paths) { notFound(w, r, filePath) return nil } exists, err := fileExists(filePath) if err != nil { return err } if !exists { notFound(w, r, filePath) return nil } startTime := time.Now() buf, err := os.ReadFile(filePath) if err != nil { return err } w.Write(buf) fileSize := humanReadableSize(len(buf)) if verbose { fmt.Printf("%s | Served %s (%s) to %s in %s\n", startTime.Format(LogDate), filePath, fileSize, realIP(r), time.Since(startTime).Round(time.Microsecond), ) } if statistics { stats.incrementCounter(filePath, startTime, fileSize) } return nil } func serveCacheClearHandler(args []string, index *Index) http.HandlerFunc { return func(w http.ResponseWriter, r *http.Request) { index.generateCache(args) w.WriteHeader(http.StatusOK) w.Header().Set("Content-Type", "text/plain") w.Write([]byte("Ok")) } } func serveStatsHandler(args []string, stats *ServeStats) http.HandlerFunc { return func(w http.ResponseWriter, r *http.Request) { w.WriteHeader(http.StatusOK) w.Header().Set("Content-Type", "application/json") startTime := time.Now() response, err := stats.ListImages() if err != nil { log.Fatal(err) } w.Write(response) if verbose { fmt.Printf("%s | Served statistics page (%s) to %s in %s\n", startTime.Format(LogDate), humanReadableSize(len(response)), realIP(r), time.Since(startTime).Round(time.Microsecond), ) } } } func serveStaticFileHandler(paths []string, stats *ServeStats) http.HandlerFunc { return func(w http.ResponseWriter, r *http.Request) { err := serveStaticFile(w, r, paths, stats) if err != nil { log.Fatal(err) } } } func serveHtmlHandler(paths []string, Regexes *Regexes, index *Index) http.HandlerFunc { return func(w http.ResponseWriter, r *http.Request) { refererUri, err := stripQueryParams(refererToUri(r.Referer())) if err != nil { log.Fatal(err) } filters := &Filters{ includes: splitQueryParams(r.URL.Query().Get("include"), Regexes), excludes: splitQueryParams(r.URL.Query().Get("exclude"), Regexes), } sortOrder := sortOrder(r) _, refreshInterval := refreshInterval(r, Regexes) if r.URL.Path == "/" { var filePath string var err error if refererUri != "" { filePath, err = nextFile(refererUri, sortOrder, Regexes) if err != nil { log.Fatal(err) } } if filePath == "" { filePath, err = newFile(paths, filters, sortOrder, Regexes, index) switch { case err != nil && err == ErrNoImagesFound: notFound(w, r, filePath) return case err != nil: log.Fatal(err) } } queryParams := generateQueryParams(filters, sortOrder, refreshInterval) newUrl := fmt.Sprintf("http://%s%s%s", r.Host, preparePath(filePath), queryParams, ) http.Redirect(w, r, newUrl, RedirectStatusCode) } else { filePath := r.URL.Path if runtime.GOOS == "windows" { filePath = strings.TrimPrefix(filePath, "/") } exists, err := fileExists(filePath) if err != nil { log.Fatal(err) } if !exists { notFound(w, r, filePath) return } image, err := isImage(filePath) if err != nil { log.Fatal(err) } if !image { notFound(w, r, filePath) return } dimensions, err := imageDimensions(filePath) if err != nil { log.Fatal(err) } err = serveHtml(w, r, filePath, dimensions, filters, Regexes) if err != nil { log.Fatal(err) } } } } func doNothing(http.ResponseWriter, *http.Request) {} func ServePage(args []string) error { fmt.Printf("roulette v%s\n\n", Version) paths, err := normalizePaths(args) if err != nil { return err } Regexes := &Regexes{ filename: regexp.MustCompile(`(.+)([0-9]{3})(\..+)`), alphanumeric: regexp.MustCompile(`^[a-zA-Z0-9]*$`), units: regexp.MustCompile(`^[0-9]+(ns|us|µs|ms|s|m|h)$`), } rand.New(rand.NewSource(time.Now().UnixNano())) index := &Index{ mutex: sync.RWMutex{}, list: []string{}, } if cache { skipIndex := false if cacheFile != "" { err = index.Import(cacheFile) switch err { case ErrIndexNotExist: case nil: skipIndex = true default: return err } } if !skipIndex { index.generateCache(args) } http.Handle("/_/clear_cache", serveCacheClearHandler(args, index)) } stats := &ServeStats{ mutex: sync.RWMutex{}, list: []string{}, count: make(map[string]uint64), size: make(map[string]string), times: make(map[string][]string), } http.Handle("/", serveHtmlHandler(paths, Regexes, index)) http.Handle(Prefix+"/", http.StripPrefix(Prefix, serveStaticFileHandler(paths, stats))) http.HandleFunc("/favicon.ico", doNothing) if statistics { http.Handle("/_/stats", serveStatsHandler(args, stats)) } err = http.ListenAndServe(":"+strconv.FormatInt(int64(port), 10), nil) if err != nil { return err } return nil }