From 2407bc83ee8b33dae5951f922a588b921a85a0d1 Mon Sep 17 00:00:00 2001
From: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com>
Date: Tue, 23 Jan 2024 15:20:29 +0100
Subject: [PATCH] Loki: Fix throwing error when no labels received (#81077)

* Loki: Fix throwing error when no labels received

* Remove es code
---
 .../plugins/datasource/loki/LanguageProvider.test.ts  | 11 +++++++++++
 .../app/plugins/datasource/loki/LanguageProvider.ts   |  3 +++
 2 files changed, 14 insertions(+)

diff --git a/public/app/plugins/datasource/loki/LanguageProvider.test.ts b/public/app/plugins/datasource/loki/LanguageProvider.test.ts
index c83324cfea9..7702a424ee5 100644
--- a/public/app/plugins/datasource/loki/LanguageProvider.test.ts
+++ b/public/app/plugins/datasource/loki/LanguageProvider.test.ts
@@ -138,6 +138,17 @@ describe('Language completion provider', () => {
         start: 1546372800000,
       });
     });
+
+    it('should work if request returns undefined', async () => {
+      const datasource = setup({});
+      datasource.getTimeRangeParams = jest
+        .fn()
+        .mockImplementation((range: TimeRange) => ({ start: range.from.valueOf(), end: range.to.valueOf() }));
+      const languageProvider = new LanguageProvider(datasource);
+      languageProvider.request = jest.fn().mockResolvedValue(undefined);
+      const series = await languageProvider.fetchSeriesLabels('stream', { timeRange: mockTimeRange });
+      expect(series).toEqual({});
+    });
   });
 
   describe('label values', () => {
diff --git a/public/app/plugins/datasource/loki/LanguageProvider.ts b/public/app/plugins/datasource/loki/LanguageProvider.ts
index 631aef68b3f..460140b35f1 100644
--- a/public/app/plugins/datasource/loki/LanguageProvider.ts
+++ b/public/app/plugins/datasource/loki/LanguageProvider.ts
@@ -172,6 +172,9 @@ export default class LokiLanguageProvider extends LanguageProvider {
     if (!value) {
       const params = { 'match[]': interpolatedMatch, start, end };
       const data = await this.request(url, params);
+      if (!Array.isArray(data)) {
+        return {};
+      }
       const { values } = processLabels(data);
       value = values;
       this.seriesCache.set(cacheKey, value);