[v10.1.x] Query splitting: combine nanos attribute con time fields (#73564)

Query splitting: combine nanos attribute con time fields (#73505)

(cherry picked from commit f7355668e7)

Co-authored-by: Matias Chomicki <matyax@gmail.com>

public/app/plugins/datasource/loki/responseUtils.test.ts

@@ -403,6 +403,81 @@ describe('combineResponses', () => {
     expect(combined.errors?.[1]?.message).toBe('errorB');
   });
 
+  it('combines frames with nanoseconds', () => {
+    const { logFrameA, logFrameB } = getMockFrames();
+    logFrameA.fields[0].nanos = [333333, 444444];
+    logFrameB.fields[0].nanos = [111111, 222222];
+    const responseA: DataQueryResponse = {
+      data: [logFrameA],
+    };
+    const responseB: DataQueryResponse = {
+      data: [logFrameB],
+    };
+    expect(combineResponses(responseA, responseB)).toEqual({
+      data: [
+        {
+          fields: [
+            {
+              config: {},
+              name: 'Time',
+              type: 'time',
+              values: [1, 2, 3, 4],
+              nanos: [111111, 222222, 333333, 444444],
+            },
+            {
+              config: {},
+              name: 'Line',
+              type: 'string',
+              values: ['line3', 'line4', 'line1', 'line2'],
+            },
+            {
+              config: {},
+              name: 'labels',
+              type: 'other',
+              values: [
+                {
+                  otherLabel: 'other value',
+                },
+                {
+                  label: 'value',
+                },
+                {
+                  otherLabel: 'other value',
+                },
+              ],
+            },
+            {
+              config: {},
+              name: 'tsNs',
+              type: 'string',
+              values: ['1000000', '2000000', '3000000', '4000000'],
+            },
+            {
+              config: {},
+              name: 'id',
+              type: 'string',
+              values: ['id3', 'id4', 'id1', 'id2'],
+            },
+          ],
+          length: 4,
+          meta: {
+            custom: {
+              frameType: 'LabeledTimeValues',
+            },
+            stats: [
+              {
+                displayName: 'Summary: total bytes processed',
+                unit: 'decbytes',
+                value: 33,
+              },
+            ],
+          },
+          refId: 'A',
+        },
+      ],
+    });
+  });
+
   describe('combine stats', () => {
     const { metricFrameA } = getMockFrames();
     const makeResponse = (stats?: QueryResultMetaStat[]): DataQueryResponse => ({

public/app/plugins/datasource/loki/responseUtils.ts

@@ -203,6 +203,10 @@ function combineFrames(dest: DataFrame, source: DataFrame) {
   const totalFields = dest.fields.length;
   for (let i = 0; i < totalFields; i++) {
     dest.fields[i].values = [].concat.apply(source.fields[i].values, dest.fields[i].values);
+    if (source.fields[i].nanos) {
+      const nanos: number[] = dest.fields[i].nanos?.slice() || [];
+      dest.fields[i].nanos = source.fields[i].nanos?.concat(nanos);
+    }
   }
   dest.length += source.length;
   dest.meta = {