/* Copyright © 2022 Seednode */ package cmd import ( "fmt" "io" "log" "math/rand" "net/http" "net/url" "os" "path/filepath" "regexp" "runtime" "strconv" "strings" "time" "github.com/yosssi/gohtml" ) 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) GetIncludes() string { return strings.Join(f.Includes, ",") } func (f *Filters) HasExcludes() bool { return len(f.Excludes) != 0 } func (f *Filters) GetExcludes() string { return strings.Join(f.Excludes, ",") } func generateCache(args []string, fileCache *[]string) error { filters := &Filters{} fmt.Printf("%v | Preparing image cache...\n", time.Now().Format(LogDate)) _, err := pickFile(args, filters, "", fileCache) return err } func notFound(w http.ResponseWriter, r *http.Request, filePath string) error { startTime := time.Now() if Verbose { fmt.Printf("%v | Unavailable file %v requested by %v\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 getRefreshInterval(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 getSortOrder(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 Filter { queryParams.WriteString("include=") if filters.HasIncludes() { queryParams.WriteString(filters.GetIncludes()) } queryParams.WriteString("&exclude=") if filters.HasExcludes() { queryParams.WriteString(filters.GetExcludes()) } hasParams = true } if Sort { if hasParams { queryParams.WriteString("&") } queryParams.WriteString(fmt.Sprintf("sort=%v", sortOrder)) hasParams = true } if hasParams { queryParams.WriteString("&") } queryParams.WriteString(fmt.Sprintf("refresh=%v", 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 getRealIp(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 := getSortOrder(r) refreshTimer, refreshInterval := getRefreshInterval(r, regexes) queryParams := generateQueryParams(filters, sortOrder, refreshInterval) var htmlBody strings.Builder htmlBody.WriteString(``) htmlBody.WriteString(``) htmlBody.WriteString(fmt.Sprintf(`%v (%vx%v)`, fileName, dimensions.Width, dimensions.Height)) htmlBody.WriteString(``) if refreshInterval != "0ms" { htmlBody.WriteString(fmt.Sprintf("", queryParams, refreshTimer)) } htmlBody.WriteString(fmt.Sprintf(`Roulette selected: %v`, 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) 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) if Verbose { fmt.Printf("%v | Served %v (%v) to %v in %v\n", startTime.Format(LogDate), filePath, humanReadableSize(len(buf)), getRealIp(r), time.Since(startTime).Round(time.Microsecond), ) } return nil } func serveStaticFileHandler(paths []string) http.HandlerFunc { return func(w http.ResponseWriter, r *http.Request) { err := serveStaticFile(w, r, paths) if err != nil { log.Fatal(err) } } } func serveHtmlHandler(paths []string, regexes *Regexes, fileCache *[]string) 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 := getSortOrder(r) _, refreshInterval := getRefreshInterval(r, regexes) if r.URL.Path == "/" { var filePath string var err error if refererUri != "" { filePath, err = getNextFile(refererUri, sortOrder, regexes) if err != nil { log.Fatal(err) } } if filePath == "" { filePath, err = getNewFile(paths, filters, sortOrder, regexes, fileCache) 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://%v%v%v", 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 := getImageDimensions(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%v\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.Seed(time.Now().UnixNano()) fileCache := &[]string{} if Cache { err := generateCache(args, fileCache) if err != nil { return err } } http.Handle("/", serveHtmlHandler(paths, regexes, fileCache)) http.Handle(Prefix+"/", http.StripPrefix(Prefix, serveStaticFileHandler(paths))) http.HandleFunc("/favicon.ico", doNothing) err = http.ListenAndServe(":"+strconv.FormatInt(int64(Port), 10), nil) if err != nil { return err } return nil }