Fix up sync client request logs (#770)

* Fix up sync client request logs

* Handle empty node id on request error in sync client logs

* Nit: pre-allocate capacity for log ctx based

peer/client.go

@@ -54,11 +54,11 @@ func (c *client) RequestAny(minVersion version.Application, request []byte) ([]b
 	waitingHandler := newWaitingResponseHandler()
 	nodeID, err := c.network.RequestAny(minVersion, request, waitingHandler)
 	if err != nil {
-		return nil, ids.EmptyNodeID, err
+		return nil, nodeID, err
 	}
 	response := <-waitingHandler.responseChan
 	if waitingHandler.failed {
-		return nil, ids.EmptyNodeID, ErrRequestFailed
+		return nil, nodeID, ErrRequestFailed
 	}
 	return response, nodeID, nil
 }

sync/client/client.go

@@ -326,7 +326,12 @@ func (c *client) get(request message.Request, parseFn parseResponseFn) (interfac
 		metric.UpdateRequestLatency(time.Since(start))
 
 		if err != nil {
-			log.Info("request failed, retrying", "nodeID", nodeID, "attempt", attempt, "request", request, "err", err)
+			ctx := make([]interface{}, 0, 8)
+			if nodeID != ids.EmptyNodeID {
+				ctx = append(ctx, "nodeID", nodeID)
+			}
+			ctx = append(ctx, "attempt", attempt, "request", request, "err", err)
+			log.Debug("request failed, retrying", ctx...)
 			metric.IncFailed()
 			continue
 		} else {