feat: update restore to support InfluxDB 2.0.x (#185)

pkg/gzip/gunzip.go

@@ -0,0 +1,30 @@
+package gzip
+
+import (
+	"compress/gzip"
+	"io"
+)
+
+func NewGunzipReadCloser(in io.ReadCloser) (*gunzipReadCloser, error) {
+	gzr, err := gzip.NewReader(in)
+	if err != nil {
+		return nil, err
+	}
+	return &gunzipReadCloser{underlying: in, gunzip: gzr}, nil
+}
+
+type gunzipReadCloser struct {
+	underlying io.ReadCloser
+	gunzip     io.ReadCloser
+}
+
+func (gzrc *gunzipReadCloser) Read(p []byte) (int, error) {
+	return gzrc.gunzip.Read(p)
+}
+
+func (gzrc *gunzipReadCloser) Close() error {
+	if err := gzrc.gunzip.Close(); err != nil {
+		return err
+	}
+	return gzrc.underlying.Close()
+}