From 26bb08e1e6db11d5ebb55d9a55f474adaffeae0b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Piotr=20Jamr=C3=B3z?= <pm.jamroz@gmail.com>
Date: Mon, 13 Sep 2021 20:10:35 +0200
Subject: [PATCH] Graphite: Fix drag and drop queries (#39130)

* Do not use "select metric" segment when rendering target

* Use better names for tests
---
 .../datasource/graphite/graphite_query.ts     |  2 +-
 .../graphite/specs/graphite_query.test.ts     | 21 +++++++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/public/app/plugins/datasource/graphite/graphite_query.ts b/public/app/plugins/datasource/graphite/graphite_query.ts
index 8b3d45bb1d2..da76d351e42 100644
--- a/public/app/plugins/datasource/graphite/graphite_query.ts
+++ b/public/app/plugins/datasource/graphite/graphite_query.ts
@@ -180,7 +180,7 @@ export default class GraphiteQuery {
     };
 
     if (!this.target.textEditor) {
-      const metricPath = this.getSegmentPathUpTo(this.segments.length).replace(/\.select metric$/, '');
+      const metricPath = this.getSegmentPathUpTo(this.segments.length).replace(/\.?select metric$/, '');
       this.target.target = reduce(this.functions, wrapFunction, metricPath);
     }
 
diff --git a/public/app/plugins/datasource/graphite/specs/graphite_query.test.ts b/public/app/plugins/datasource/graphite/specs/graphite_query.test.ts
index 62e5c08505e..16ab9616b01 100644
--- a/public/app/plugins/datasource/graphite/specs/graphite_query.test.ts
+++ b/public/app/plugins/datasource/graphite/specs/graphite_query.test.ts
@@ -74,4 +74,25 @@ describe('Graphite query model', () => {
       expect(ctx.queryModel.functions[1].params[0]).toBe('$limit');
     });
   });
+
+  describe('when query is generated from segments', () => {
+    beforeEach(() => {
+      ctx.target = { refId: 'A', target: '' };
+      ctx.queryModel = new GraphiteQuery(ctx.datasource, ctx.target, ctx.templateSrv);
+    });
+
+    it('and no segments are selected then the query is empty', () => {
+      ctx.queryModel.segments = [{ value: 'select metric' }];
+      ctx.queryModel.updateModelTarget(ctx.targets);
+
+      expect(ctx.queryModel.target.target).toBe('');
+    });
+
+    it('and some segments are selected then segments without selected value are omitted', () => {
+      ctx.queryModel.segments = [{ value: 'foo' }, { value: 'bar' }, { value: 'select metric' }];
+      ctx.queryModel.updateModelTarget(ctx.targets);
+
+      expect(ctx.queryModel.target.target).toBe('foo.bar');
+    });
+  });
 });