From 9ce3b7e1dde341f777600769c905e5a31b599389 Mon Sep 17 00:00:00 2001
From: Aliaksandr Valialkin <valyala@gmail.com>
Date: Wed, 7 Apr 2021 23:33:40 +0300
Subject: [PATCH] app/vmselect: return `data:null` instead of `data:[]` from
 `/api/v1/query_exemplars`, since Grafana throws an error otherwise

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1186
---
 app/vmselect/main.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/vmselect/main.go b/app/vmselect/main.go
index d2ea27be27..344f9c38cb 100644
--- a/app/vmselect/main.go
+++ b/app/vmselect/main.go
@@ -451,7 +451,7 @@ func selectHandler(startTime time.Time, w http.ResponseWriter, r *http.Request,
 		// Return dumb placeholder for https://prometheus.io/docs/prometheus/latest/querying/api/#querying-exemplars
 		queryExemplarsRequests.Inc()
 		w.Header().Set("Content-Type", "application/json; charset=utf-8")
-		fmt.Fprintf(w, "%s", `{"status":"success","data":[]}`)
+		fmt.Fprintf(w, "%s", `{"status":"success","data":null}`)
 		return true
 	default:
 		return false