Wrap a reader to a gzip compress reader using gzip writer :-P

gzip_compress_reader.go

func NewGzipReader(source io.Reader) io.Reader {
	r, w := io.Pipe()
	go func() {
		defer w.Close()

		zip, err := gzip.NewWriterLevel(w, gzip.BestSpeed)
		defer zip.Close()
		if err != nil {
			w.CloseWithError(err)
		}

		io.Copy(zip, source)
	}()
	return r
}

Better add err handling also around the io.Copy:

		_, err = io.Copy(zip, source)
		if err != nil {
			w.CloseWithError(err)
		}