feat(backup): Add backup/restore to the server

api/archive/targz.go

@@ -0,0 +1,119 @@
+package archive
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// TarGzDir creates a tar.gz archive and returns it's path.
+// abosolutePath should be an absolute path to a directory.
+// Archive name will be <directoryName>.tar.gz and will be placed next to the directory.
+func TarGzDir(absolutePath string) (string, error) {
+	targzPath := filepath.Join(absolutePath, fmt.Sprintf("%s.tar.gz", filepath.Base(absolutePath)))
+	outFile, err := os.Create(targzPath)
+	if err != nil {
+		return "", err
+	}
+	defer outFile.Close()
+
+	zipWriter := gzip.NewWriter(outFile)
+	defer zipWriter.Close()
+	tarWriter := tar.NewWriter(zipWriter)
+	defer tarWriter.Close()
+
+	err = filepath.Walk(absolutePath, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		if path == targzPath {
+			return nil // skip archive file
+		}
+
+		pathInArchive := filepath.Clean(strings.TrimPrefix(path, absolutePath))
+		if pathInArchive == "" {
+			return nil // skip root dir
+		}
+
+		return addToArchive(tarWriter, pathInArchive, path, info)
+	})
+
+	return targzPath, err
+}
+
+func addToArchive(tarWriter *tar.Writer, pathInArchive string, path string, info os.FileInfo) error {
+	header, err := tar.FileInfoHeader(info, info.Name())
+	if err != nil {
+		return err
+	}
+
+	header.Name = pathInArchive // use relative paths in archive
+
+	err = tarWriter.WriteHeader(header)
+	if err != nil {
+		return err
+	}
+
+	if info.IsDir() {
+		return nil
+	}
+
+	file, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(tarWriter, file)
+	return err
+}
+
+// ExtractTarGz reads a .tar.gz archive from the reader and extracts it into outputDirPath directory
+func ExtractTarGz(r io.Reader, outputDirPath string) error {
+	zipReader, err := gzip.NewReader(r)
+	if err != nil {
+		return err
+	}
+	defer zipReader.Close()
+
+	tarReader := tar.NewReader(zipReader)
+
+	for {
+		header, err := tarReader.Next()
+
+		if err == io.EOF {
+			break
+		}
+
+		if err != nil {
+			return err
+		}
+
+		switch header.Typeflag {
+		case tar.TypeDir:
+			// skip, dir will be created with a file
+		case tar.TypeReg:
+			p := filepath.Clean(filepath.Join(outputDirPath, header.Name))
+			if err := os.MkdirAll(filepath.Dir(p), 0744); err != nil {
+				return fmt.Errorf("Failed to extract dir %s", filepath.Dir(p))
+			}
+			outFile, err := os.Create(p)
+			if err != nil {
+				return fmt.Errorf("Failed to create file %s", header.Name)
+			}
+			if _, err := io.Copy(outFile, tarReader); err != nil {
+				return fmt.Errorf("Failed to extract file %s", header.Name)
+			}
+			outFile.Close()
+		default:
+			return fmt.Errorf("Tar: uknown type: %v in %s",
+				header.Typeflag,
+				header.Name)
+		}
+	}
+
+	return nil
+}