wisski-cloud-distillery/pkg/targz/targz.go
2023-03-02 11:38:30 +01:00

92 lines
1.9 KiB
Go

// Package targz provides facilities for packaging tar.gz files
package targz
import (
"archive/tar"
"compress/gzip"
"io"
"io/fs"
"os"
"path/filepath"
"github.com/FAU-CDI/wisski-distillery/pkg/environment"
"github.com/FAU-CDI/wisski-distillery/pkg/fsx"
)
// Package packages the source directory into a 'tar.gz' file into destination.
// If the destination already exists, it is truncated.
//
// onCopy, when not nil, is called for each file being copied into the archive.
func Package(env environment.Environment, dst, src string, onCopy func(rel string, src string)) (count int64, err error) {
// create the target archive
archive, err := fsx.Create(dst, fsx.DefaultFilePerm)
if err != nil {
return 0, err
}
defer archive.Close()
// create a gzip writer
zipHandle := gzip.NewWriter(archive)
defer zipHandle.Close()
// create a tar writer
tarHandle := tar.NewWriter(zipHandle)
defer tarHandle.Close()
// and walk through it!
err = filepath.WalkDir(src, func(path string, entry fs.DirEntry, err error) error {
if err != nil {
return err
}
// determine the relative path
var relpath string
relpath, err = filepath.Rel(src, path)
if err != nil {
return err
}
// call the oncopy!
if onCopy != nil {
onCopy(relpath, path)
}
// read mode etc
info, err := entry.Info()
if err != nil {
return err
}
// FIXME: How do we handle
// create a file info header!
tInfo, err := tar.FileInfoHeader(info, relpath)
if err != nil {
return err
}
tInfo.Name = filepath.ToSlash(relpath)
// write it!
if err := tarHandle.WriteHeader(tInfo); err != nil {
return err
}
// if it's not a regular file, we are done
if !entry.Type().IsRegular() {
return nil
}
// open the file
handle, err := os.Open(path)
if err != nil {
return err
}
defer handle.Close()
// and copy it into the archive
ccount, err := io.Copy(tarHandle, handle)
count += ccount
return err
})
return
}