Merge pull request #14033 from ahrtr/hide_revision

Hide the revision field when it isn't populated

api/etcdserverpb/rpc.proto

@@ -395,7 +395,8 @@ message ResponseHeader {
   uint64 cluster_id = 1;
   // member_id is the ID of the member which sent the response.
   uint64 member_id = 2;
-  // revision is the key-value store revision when the request was applied.
+  // revision is the key-value store revision when the request was applied, and it's
+  // unset (so 0) in case of calls not interacting with key-value store.
   // For watch progress responses, the header.revision indicates progress. All future events
   // received in this stream are guaranteed to have a higher revision number than the
   // header.revision number.

etcdctl/ctlv3/command/printer_fields.go

@@ -36,7 +36,12 @@ func (p *fieldsPrinter) kv(pfx string, kv *spb.KeyValue) {
 func (p *fieldsPrinter) hdr(h *pb.ResponseHeader) {
 	fmt.Println(`"ClusterID" :`, h.ClusterId)
 	fmt.Println(`"MemberID" :`, h.MemberId)
-	fmt.Println(`"Revision" :`, h.Revision)
+	// Revision only makes sense for k/v responses. For other kinds of
+	// responses, i.e. MemberList, usually the revision isn't populated
+	// at all; so it would be better to hide this field in these cases.
+	if h.Revision > 0 {
+		fmt.Println(`"Revision" :`, h.Revision)
+	}
 	fmt.Println(`"RaftTerm" :`, h.RaftTerm)
 }