Explore: Keep logQL filters when selecting labels in log row details (#20570)

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

@@ -5,7 +5,7 @@ import { map, filter, catchError, switchMap, mergeMap } from 'rxjs/operators';
 
 // Services & Utils
 import { dateMath } from '@grafana/data';
-import { addLabelToSelector } from 'app/plugins/datasource/prometheus/add_label_to_query';
+import { addLabelToSelector, keepSelectorFilters } from 'app/plugins/datasource/prometheus/add_label_to_query';
 import { BackendSrv, DatasourceRequestOptions } from 'app/core/services/backend_srv';
 import { TemplateSrv } from 'app/features/templating/template_srv';
 import { safeStringifyValue, convertToWebSocketUrl } from 'app/core/utils/explore';
@@ -413,13 +413,18 @@ export class LokiDatasource extends DataSourceApi<LokiQuery, LokiOptions> {
   modifyQuery(query: LokiQuery, action: any): LokiQuery {
     const parsed = parseQuery(query.expr || '');
     let { query: selector } = parsed;
+    let selectorLabels, selectorFilters;
     switch (action.type) {
       case 'ADD_FILTER': {
-        selector = addLabelToSelector(selector, action.key, action.value);
+        selectorLabels = addLabelToSelector(selector, action.key, action.value);
+        selectorFilters = keepSelectorFilters(selector);
+        selector = `${selectorLabels} ${selectorFilters}`;
         break;
       }
       case 'ADD_FILTER_OUT': {
-        selector = addLabelToSelector(selector, action.key, action.value, '!=');
+        selectorLabels = addLabelToSelector(selector, action.key, action.value, '!=');
+        selectorFilters = keepSelectorFilters(selector);
+        selector = `${selectorLabels} ${selectorFilters}`;
         break;
       }
       default:

public/app/plugins/datasource/prometheus/add_label_to_query.ts

@@ -91,6 +91,12 @@ export function addLabelToSelector(selector: string, labelKey: string, labelValu
   return `{${formatted}}`;
 }
 
+export function keepSelectorFilters(selector: string) {
+  // Remove all label-key between {} and return filters. If first character is space, remove it.
+  const filters = selector.replace(/\{(.*?)\}/g, '').replace(/^ /, '');
+  return filters;
+}
+
 function isPositionInsideChars(text: string, position: number, openChar: string, closeChar: string) {
   const nextSelectorStart = text.slice(position).indexOf(openChar);
   const nextSelectorEnd = text.slice(position).indexOf(closeChar);

public/app/plugins/datasource/prometheus/specs/add_label_to_query.test.ts

-import { addLabelToQuery, addLabelToSelector } from '../add_label_to_query';
+import { addLabelToQuery, addLabelToSelector, keepSelectorFilters } from '../add_label_to_query';
 
 describe('addLabelToQuery()', () => {
   it('should add label to simple query', () => {
@@ -44,7 +44,7 @@ describe('addLabelToQuery()', () => {
     );
   });
 
-  it('should not add duplicate labels to aquery', () => {
+  it('should not add duplicate labels to a query', () => {
     expect(addLabelToQuery(addLabelToQuery('foo{x="yy"}', 'bar', 'baz', '!='), 'bar', 'baz', '!=')).toBe(
       'foo{bar!="baz",x="yy"}'
     );
@@ -72,3 +72,15 @@ describe('addLabelToSelector()', () => {
     expect(addLabelToSelector('{}', 'baz', '42', '!=')).toBe('{baz!="42"}');
   });
 });
+
+describe('keepSelectorFilters()', () => {
+  test('should return empty string if no filter is in selector', () => {
+    expect(keepSelectorFilters('{foo="bar"}')).toBe('');
+  });
+  test('should return a filter if filter is in selector', () => {
+    expect(keepSelectorFilters('{foo="bar"} |="baz"')).toBe('|="baz"');
+  });
+  test('should return multiple filters if multiple filters are in selector', () => {
+    expect(keepSelectorFilters('{foo!="bar"} |="baz" |~"yy" !~"xx"')).toBe('|="baz" |~"yy" !~"xx"');
+  });
+});