Loki: Remove appending of (?i) in Loki query editor if not added by user (#20908)

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

@@ -439,13 +439,13 @@ export class LokiDatasource extends DataSourceApi<LokiQuery, LokiOptions> {
       case 'ADD_FILTER': {
         selectorLabels = addLabelToSelector(selector, action.key, action.value);
         selectorFilters = keepSelectorFilters(selector);
-        selector = `${selectorLabels} ${selectorFilters}`;
+        selector = `${selectorLabels} ${selectorFilters}`.trim();
         break;
       }
       case 'ADD_FILTER_OUT': {
         selectorLabels = addLabelToSelector(selector, action.key, action.value, '!=');
         selectorFilters = keepSelectorFilters(selector);
-        selector = `${selectorLabels} ${selectorFilters}`;
+        selector = `${selectorLabels} ${selectorFilters}`.trim();
         break;
       }
       default:

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

@@ -26,14 +26,14 @@ describe('parseQuery', () => {
   it('returns query for strings with query and search string', () => {
     expect(parseQuery('x {foo="bar"}')).toEqual({
       query: '{foo="bar"}',
-      regexp: '(?i)x',
+      regexp: 'x',
     } as LokiExpression);
   });
 
   it('returns query for strings with query and regexp', () => {
     expect(parseQuery('{foo="bar"} x|y')).toEqual({
       query: '{foo="bar"}',
-      regexp: '(?i)x|y',
+      regexp: 'x|y',
     } as LokiExpression);
   });
 
@@ -47,11 +47,11 @@ describe('parseQuery', () => {
   it('returns query and regexp with quantifiers', () => {
     expect(parseQuery('{foo="bar"} \\.java:[0-9]{1,5}')).toEqual({
       query: '{foo="bar"}',
-      regexp: '(?i)\\.java:[0-9]{1,5}',
+      regexp: '\\.java:[0-9]{1,5}',
     } as LokiExpression);
     expect(parseQuery('\\.java:[0-9]{1,5} {foo="bar"}')).toEqual({
       query: '{foo="bar"}',
-      regexp: '(?i)\\.java:[0-9]{1,5}',
+      regexp: '\\.java:[0-9]{1,5}',
     } as LokiExpression);
   });
 
@@ -73,8 +73,8 @@ describe('getHighlighterExpressionsFromQuery', () => {
   });
 
   it('returns a single expressions for legacy query', () => {
-    expect(getHighlighterExpressionsFromQuery('{} x')).toEqual(['(?i)x']);
-    expect(getHighlighterExpressionsFromQuery('{foo="bar"} x')).toEqual(['(?i)x']);
+    expect(getHighlighterExpressionsFromQuery('{} x')).toEqual(['x']);
+    expect(getHighlighterExpressionsFromQuery('{foo="bar"} x')).toEqual(['x']);
   });
 
   it('returns an expression for query with filter', () => {

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

 import { LokiExpression } from './types';
 
 const selectorRegexp = /(?:^|\s){[^{]*}/g;
-const caseInsensitive = '(?i)'; // Golang mode modifier for Loki, doesn't work in JavaScript
 export function parseQuery(input: string): LokiExpression {
   input = input || '';
   const match = input.match(selectorRegexp);
@@ -9,13 +8,11 @@ export function parseQuery(input: string): LokiExpression {
   let regexp = '';
 
   if (match) {
+    // Regexp result is ignored on the server side
     regexp = input.replace(selectorRegexp, '').trim();
     // Keep old-style regexp, otherwise take whole query
     if (regexp && regexp.search(/\|=|\|~|!=|!~/) === -1) {
       query = match[0].trim();
-      if (!regexp.startsWith(caseInsensitive)) {
-        regexp = `${caseInsensitive}${regexp}`;
-      }
     } else {
       regexp = '';
     }