easy way to unzip file with golang

Question

is there a easy way to unzip file with golang ?

right now my code is:

func Unzip(src, dest string) error {
    r, err := zip.OpenReader(src)
    if err != nil {
        return err
    }
    defer r.Close()

    for _, f := range r.File {
        rc, err := f.Open()
        if err != nil {
            return err
        }
        defer rc.Close()

        path := filepath.Join(dest, f.Name)
        if f.FileInfo().IsDir() {
            os.MkdirAll(path, f.Mode())
        } else {
            f, err := os.OpenFile(
                path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode())
            if err != nil {
                return err
            }
            defer f.Close()

            _, err = io.Copy(f, rc)
            if err != nil {
                return err
            }
        }
    }

    return nil
}

Answer 1

Slight rework of the OP's solution to create the containing directory dest if it doesn't exist, and to wrap the file extraction/writing in a closure to eliminate stacking of defer .Close() calls per @Nick Craig-Wood's comment:

func Unzip(src, dest string) error {
    r, err := zip.OpenReader(src)
    if err != nil {
        return err
    }
    defer func() {
        if err := r.Close(); err != nil {
            panic(err)
        }
    }()

    os.MkdirAll(dest, 0755)

    // Closure to address file descriptors issue with all the deferred .Close() methods
    extractAndWriteFile := func(f *zip.File) error {
        rc, err := f.Open()
        if err != nil {
            return err
        }
        defer func() {
            if err := rc.Close(); err != nil {
                panic(err)
            }
        }()

        path := filepath.Join(dest, f.Name)

        // Check for ZipSlip (Directory traversal)
        if !strings.HasPrefix(path, filepath.Clean(dest) + string(os.PathSeparator)) {
            return fmt.Errorf("illegal file path: %s", path)
        }

        if f.FileInfo().IsDir() {
            os.MkdirAll(path, f.Mode())
        } else {
            os.MkdirAll(filepath.Dir(path), f.Mode())
            f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode())
            if err != nil {
                return err
            }
            defer func() {
                if err := f.Close(); err != nil {
                    panic(err)
                }
            }()

            _, err = io.Copy(f, rc)
            if err != nil {
                return err
            }
        }
        return nil
    }

    for _, f := range r.File {
        err := extractAndWriteFile(f)
        if err != nil {
            return err
        }
    }

    return nil
}

Note: Updated to include Close() error handling as well (if we're looking for best practices, may as well follow ALL of them).