Merge pull request #4051 from xiang90/log

rafthttp: log before receiving snapshot

rafthttp/http.go

@@ -169,6 +169,7 @@ func (h *snapshotHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	plog.Infof("receiving database snapshot [index:%d, from %s] ...", m.Snapshot.Metadata.Index, types.ID(m.From))
 	// save incoming database snapshot.
 	if err := h.snapshotter.SaveDBFrom(r.Body, m.Snapshot.Metadata.Index); err != nil {
 		msg := fmt.Sprintf("failed to save KV snapshot (%v)", err)