Explore: Fix how log bars in graph are stacking (#19015)

public/app/core/logs_model.ts

@@ -24,6 +24,7 @@ import {
 } from '@grafana/data';
 import { getThemeColor } from 'app/core/utils/colors';
 import { hasAnsiCodes } from 'app/core/utils/text';
+import { sortInAscendingOrder } from 'app/core/utils/explore';
 import { getGraphSeriesModel } from 'app/plugins/panel/graph2/getGraphSeriesModel';
 
 export const LogLevelColor = {
@@ -106,7 +107,8 @@ export function makeSeriesForLogs(rows: LogRowModel[], intervalMs: number): Grap
   const bucketSize = intervalMs * 10;
   const seriesList: any[] = [];
 
-  for (const row of rows) {
+  const sortedRows = rows.sort(sortInAscendingOrder);
+  for (const row of sortedRows) {
     let series = seriesByLevel[row.logLevel];
 
     if (!series) {
@@ -120,8 +122,9 @@ export function makeSeriesForLogs(rows: LogRowModel[], intervalMs: number): Grap
       seriesList.push(series);
     }
 
-    // align time to bucket size
-    const time = Math.round(row.timeEpochMs / bucketSize) * bucketSize;
+    // align time to bucket size - used Math.floor for calculation as time of the bucket
+    // must be in the past (before Date.now()) to be displayed on the graph
+    const time = Math.floor(row.timeEpochMs / bucketSize) * bucketSize;
 
     // Entry for time
     if (time === series.lastTs) {

public/app/core/specs/logs_model.test.ts

@@ -291,7 +291,7 @@ describe('dataFrameToLogsModel', () => {
     ]);
   });
 
-  it('given multiple series should return expected logs model', () => {
+  it('given multiple series with unique times should return expected logs model', () => {
     const series: DataFrame[] = [
       toDataFrame({
         labels: {
@@ -337,18 +337,18 @@ describe('dataFrameToLogsModel', () => {
     expect(logsModel.hasUniqueLabels).toBeTruthy();
     expect(logsModel.rows).toHaveLength(3);
     expect(logsModel.rows).toMatchObject([
-      {
-        entry: 'WARN boooo',
-        labels: { foo: 'bar', baz: '1' },
-        logLevel: LogLevel.debug,
-        uniqueLabels: { baz: '1' },
-      },
       {
         entry: 'INFO 1',
         labels: { foo: 'bar', baz: '2' },
         logLevel: LogLevel.error,
         uniqueLabels: { baz: '2' },
       },
+      {
+        entry: 'WARN boooo',
+        labels: { foo: 'bar', baz: '1' },
+        logLevel: LogLevel.debug,
+        uniqueLabels: { baz: '1' },
+      },
       {
         entry: 'INFO 2',
         labels: { foo: 'bar', baz: '2' },
@@ -367,4 +367,96 @@ describe('dataFrameToLogsModel', () => {
       kind: LogsMetaKind.LabelsMap,
     });
   });
+  //
+  it('given multiple series with equal times should return expected logs model', () => {
+    const series: DataFrame[] = [
+      toDataFrame({
+        labels: {
+          foo: 'bar',
+          baz: '1',
+          level: 'dbug',
+        },
+        fields: [
+          {
+            name: 'ts',
+            type: FieldType.time,
+            values: ['1970-01-01T00:00:00Z'],
+          },
+          {
+            name: 'line',
+            type: FieldType.string,
+            values: ['WARN boooo 1'],
+          },
+        ],
+      }),
+      toDataFrame({
+        labels: {
+          foo: 'bar',
+          baz: '2',
+          level: 'dbug',
+        },
+        fields: [
+          {
+            name: 'ts',
+            type: FieldType.time,
+            values: ['1970-01-01T00:00:01Z'],
+          },
+          {
+            name: 'line',
+            type: FieldType.string,
+            values: ['WARN boooo 2'],
+          },
+        ],
+      }),
+      toDataFrame({
+        name: 'logs',
+        labels: {
+          foo: 'bar',
+          baz: '2',
+          level: 'err',
+        },
+        fields: [
+          {
+            name: 'time',
+            type: FieldType.time,
+            values: ['1970-01-01T00:00:00Z', '1970-01-01T00:00:01Z'],
+          },
+          {
+            name: 'message',
+            type: FieldType.string,
+            values: ['INFO 1', 'INFO 2'],
+          },
+        ],
+      }),
+    ];
+    const logsModel = dataFrameToLogsModel(series, 0);
+    expect(logsModel.hasUniqueLabels).toBeTruthy();
+    expect(logsModel.rows).toHaveLength(4);
+    expect(logsModel.rows).toMatchObject([
+      {
+        entry: 'WARN boooo 1',
+        labels: { foo: 'bar', baz: '1' },
+        logLevel: LogLevel.debug,
+        uniqueLabels: { baz: '1' },
+      },
+      {
+        entry: 'INFO 1',
+        labels: { foo: 'bar', baz: '2' },
+        logLevel: LogLevel.error,
+        uniqueLabels: { baz: '2' },
+      },
+      {
+        entry: 'WARN boooo 2',
+        labels: { foo: 'bar', baz: '2' },
+        logLevel: LogLevel.debug,
+        uniqueLabels: { baz: '2' },
+      },
+      {
+        entry: 'INFO 2',
+        labels: { foo: 'bar', baz: '2' },
+        logLevel: LogLevel.error,
+        uniqueLabels: { baz: '2' },
+      },
+    ]);
+  });
 });

public/app/core/utils/explore.ts

@@ -464,7 +464,7 @@ export const getRefIds = (value: any): string[] => {
   return _.uniq(_.flatten(refIds));
 };
 
-const sortInAscendingOrder = (a: LogRowModel, b: LogRowModel) => {
+export const sortInAscendingOrder = (a: LogRowModel, b: LogRowModel) => {
   if (a.timestamp < b.timestamp) {
     return -1;
   }