Initial QSfera import

Server/vendor/github.com/open-policy-agent/opa/internal/file/archive/tarball.go

@@ -0,0 +1,75 @@
+package archive
+
+import (
+	"archive/tar"
+	"bytes"
+	"compress/gzip"
+	"encoding/json"
+	"errors"
+	"io"
+	"strings"
+)
+
+type TarGzWriter struct {
+	*tar.Writer
+
+	gw *gzip.Writer
+}
+
+func NewTarGzWriter(w io.Writer) *TarGzWriter {
+	gw := gzip.NewWriter(w)
+	tw := tar.NewWriter(gw)
+
+	return &TarGzWriter{
+		Writer: tw,
+		gw:     gw,
+	}
+}
+
+func (tgw *TarGzWriter) WriteFile(path string, bs []byte) (err error) {
+	hdr := &tar.Header{
+		Name:     path,
+		Mode:     0600,
+		Typeflag: tar.TypeReg,
+		Size:     int64(len(bs)),
+	}
+
+	if err = tgw.WriteHeader(hdr); err == nil {
+		_, err = tgw.Write(bs)
+	}
+
+	return err
+}
+
+func (tgw *TarGzWriter) WriteJSONFile(path string, v any) error {
+	buf := &bytes.Buffer{}
+	if err := json.NewEncoder(buf).Encode(v); err != nil {
+		return err
+	}
+
+	return tgw.WriteFile(path, buf.Bytes())
+}
+
+func (tgw *TarGzWriter) Close() error {
+	return errors.Join(tgw.Writer.Close(), tgw.gw.Close())
+}
+
+// MustWriteTarGz writes the list of file names and content into a tarball.
+// Paths are prefixed with "/".
+func MustWriteTarGz(files [][2]string) *bytes.Buffer {
+	buf := &bytes.Buffer{}
+	tgw := NewTarGzWriter(buf)
+	defer tgw.Close()
+
+	for _, file := range files {
+		if !strings.HasPrefix(file[0], "/") {
+			file[0] = "/" + file[0]
+		}
+
+		if err := tgw.WriteFile(file[0], []byte(file[1])); err != nil {
+			panic(err)
+		}
+	}
+
+	return buf
+}