webclient: allow to download multiple files as zip

httpd/api_utils.go

@@ -3,14 +3,19 @@ package httpd
 import (
 	"context"
 	"errors"
+	"io"
 	"net/http"
 	"os"
+	"path"
 	"strconv"
+	"strings"
 
 	"github.com/go-chi/render"
+	"github.com/klauspost/compress/zip"
 
 	"github.com/drakkan/sftpgo/common"
 	"github.com/drakkan/sftpgo/dataprovider"
+	"github.com/drakkan/sftpgo/logger"
 )
 
 func sendAPIResponse(w http.ResponseWriter, r *http.Request, err error, message string, code int) {
@@ -90,3 +95,74 @@ func getSearchFilters(w http.ResponseWriter, r *http.Request) (int, int, string,
 
 	return limit, offset, order, err
 }
+
+func renderCompressedFiles(w http.ResponseWriter, conn *Connection, baseDir string, files []string) {
+	w.Header().Set("Content-Type", "application/zip")
+	w.Header().Set("Accept-Ranges", "none")
+	w.Header().Set("Content-Transfer-Encoding", "binary")
+	w.WriteHeader(http.StatusOK)
+
+	wr := zip.NewWriter(w)
+
+	for _, file := range files {
+		fullPath := path.Join(baseDir, file)
+		if err := addZipEntry(wr, conn, fullPath, baseDir); err != nil {
+			panic(http.ErrAbortHandler)
+		}
+	}
+	if err := wr.Close(); err != nil {
+		conn.Log(logger.LevelWarn, "unable to close zip file: %v", err)
+		panic(http.ErrAbortHandler)
+	}
+}
+
+func addZipEntry(wr *zip.Writer, conn *Connection, entryPath, baseDir string) error {
+	info, err := conn.Stat(entryPath, 1)
+	if err != nil {
+		conn.Log(logger.LevelDebug, "unable to add zip entry %#v, stat error: %v", entryPath, err)
+		return err
+	}
+	if info.IsDir() {
+		_, err := wr.Create(getZipEntryName(entryPath, baseDir) + "/")
+		if err != nil {
+			conn.Log(logger.LevelDebug, "unable to create zip entry %#v: %v", entryPath, err)
+			return err
+		}
+		contents, err := conn.ReadDir(entryPath)
+		if err != nil {
+			conn.Log(logger.LevelDebug, "unable to add zip entry %#v, read dir error: %v", entryPath, err)
+			return err
+		}
+		for _, info := range contents {
+			fullPath := path.Join(entryPath, info.Name())
+			if err := addZipEntry(wr, conn, fullPath, baseDir); err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+	if !info.Mode().IsRegular() {
+		// we only allow regular files
+		conn.Log(logger.LevelDebug, "skipping zip entry for non regular file %#v", entryPath)
+		return nil
+	}
+	reader, err := conn.getFileReader(entryPath, 0, http.MethodGet)
+	if err != nil {
+		conn.Log(logger.LevelDebug, "unable to add zip entry %#v, cannot open file: %v", entryPath, err)
+		return err
+	}
+	defer reader.Close()
+
+	f, err := wr.Create(getZipEntryName(entryPath, baseDir))
+	if err != nil {
+		conn.Log(logger.LevelDebug, "unable to create zip entry %#v: %v", entryPath, err)
+		return err
+	}
+	_, err = io.Copy(f, reader)
+	return err
+}
+
+func getZipEntryName(entryPath, baseDir string) string {
+	entryPath = strings.TrimPrefix(entryPath, baseDir)
+	return strings.TrimPrefix(entryPath, "/")
+}