Loki: Remove `instant` query type from Log queries (#90137)

* Loki: Prevent log queries to run as `instant` query

* Loki: add tests

* Loki: only overwrite instant queries

* Loki: fix tests

* Loki: fix tests

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

@@ -1362,13 +1362,14 @@ describe('LokiDatasource', () => {
       expect(ds.getSupplementaryRequest(SupplementaryQueryType.LogsVolume, options)).toBeDefined();
     });
 
-    it('does not create provider if there is only an instant logs query', () => {
+    it('does create provider if there is only an instant logs query', () => {
+      // we changed logic to automatically run logs queries as range queries, thus there's a provider now
       const options: DataQueryRequest<LokiQuery> = {
         ...baseRequestOptions,
         targets: [{ expr: '{label="value"', refId: 'A', queryType: LokiQueryType.Instant }],
       };
 
-      expect(ds.getSupplementaryRequest(SupplementaryQueryType.LogsVolume, options)).not.toBeDefined();
+      expect(ds.getSupplementaryRequest(SupplementaryQueryType.LogsVolume, options)).toBeDefined();
     });
   });
 
@@ -1454,7 +1455,8 @@ describe('LokiDatasource', () => {
         });
       });
 
-      it('does not return logs volume query for instant log query', () => {
+      it('does return logs volume query for instant log query', () => {
+        // we changed logic to automatically run logs queries as range queries, thus there's a volume query now
         expect(
           ds.getSupplementaryQuery(
             { type: SupplementaryQueryType.LogsVolume },
@@ -1464,7 +1466,13 @@ describe('LokiDatasource', () => {
               refId: 'A',
             }
           )
-        ).toEqual(undefined);
+        ).toEqual({
+          expr: 'sum by (level) (count_over_time({label="value"} | drop __error__[$__auto]))',
+          legendFormat: '{{ level }}',
+          queryType: 'range',
+          refId: 'log-volume-A',
+          supportingQueryType: 'logsVolume',
+        });
       });
 
       it('does not return logs volume query for metric query', () => {

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

@@ -27,8 +27,7 @@ jest.mock('@grafana/runtime', () => {
                 {
                   datasource: { type: 'loki', uid: 'abc' },
                   editorMode: 'builder',
-                  expr: '{place="$place"} |= `error`',
-                  maxLines: 60,
+                  expr: 'count_over_time({place="$place"} [5m])',
                   queryType: 'instant',
                   refId: 'A',
                 },
@@ -77,11 +76,11 @@ describe('queriesOnInitDashboard', () => {
       org_id: 1,
       code_mode_queries_count: 2,
       instant_queries_count: 1,
-      logs_queries_count: 2,
-      metric_queries_count: 3,
+      logs_queries_count: 1,
+      metric_queries_count: 4,
       queries_count: 5,
       queries_with_changed_legend_count: 3,
-      queries_with_changed_line_limit_count: 2,
+      queries_with_changed_line_limit_count: 1,
       queries_with_changed_resolution_count: 0,
       queries_with_template_variables_count: 2,
       range_queries_count: 4,

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

@@ -133,7 +133,7 @@ describe('getNormalizedLokiQuery', () => {
   it('removes deprecated instant property', () => {
     const input: LokiQuery = { refId: 'A', expr: 'test1', instant: true };
     const output = getNormalizedLokiQuery(input);
-    expect(output).toStrictEqual({ refId: 'A', expr: 'test1', queryType: LokiQueryType.Instant });
+    expect(output).toStrictEqual({ refId: 'A', expr: 'test1', queryType: LokiQueryType.Range });
   });
 
   it('removes deprecated range property', () => {

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

@@ -91,9 +91,16 @@ export function getStringsFromLineFilter(filter: SyntaxNode): SyntaxNode[] {
 }
 
 export function getNormalizedLokiQuery(query: LokiQuery): LokiQuery {
-  const queryType = getLokiQueryType(query);
+  let queryType = getLokiQueryType(query);
   // instant and range are deprecated, we want to remove them
   const { instant, range, ...rest } = query;
+
+  // if `query.expr` is not parsable this might throw an error
+  try {
+    if (isLogsQuery(query.expr) && queryType === LokiQueryType.Instant) {
+      queryType = LokiQueryType.Range;
+    }
+  } catch (e) {}
   return { ...rest, queryType };
 }
 
@@ -200,7 +207,8 @@ export function isQueryWithError(query: string): boolean {
 }
 
 export function isLogsQuery(query: string): boolean {
-  return !isQueryWithNode(query, MetricExpr);
+  // As a safeguard we are checking for a length of 2, because at least the query should be `{}`
+  return query.trim().length > 2 && !isQueryWithNode(query, MetricExpr);
 }
 
 export function isQueryWithParser(query: string): { queryWithParser: boolean; parserCount: number } {

public/app/plugins/datasource/loki/querybuilder/components/LokiQueryBuilderOptions.test.tsx

@@ -151,6 +151,17 @@ describe('LokiQueryBuilderOptions', () => {
     await userEvent.click(screen.getByRole('button', { name: /Options/ }));
     expect(screen.queryByText(/Invalid step/)).not.toBeInTheDocument();
   });
+
+  it('does not show instant type when using a log query', async () => {
+    setup({ expr: '{foo="bar"}', queryType: LokiQueryType.Instant });
+    expect(screen.queryByText(/Instant/)).not.toBeInTheDocument();
+  });
+
+  it('does not show instant type in the options when using a log query', async () => {
+    setup({ expr: '{foo="bar"}', step: '1m' });
+    await userEvent.click(screen.getByRole('button', { name: /Options/ }));
+    expect(screen.queryByText(/Instant/)).not.toBeInTheDocument();
+  });
 });
 
 function setup(queryOverrides: Partial<LokiQuery> = {}) {

public/app/plugins/datasource/loki/querybuilder/components/LokiQueryBuilderOptions.tsx

@@ -67,8 +67,17 @@ export const LokiQueryBuilderOptions = React.memo<Props>(
       onRunQuery();
     }
 
-    const queryType = getLokiQueryType(query);
+    let queryType = getLokiQueryType(query);
     const isLogQuery = isLogsQuery(query.expr);
+    const filteredQueryTypeOptions = isLogQuery
+      ? queryTypeOptions.filter((o) => o.value !== LokiQueryType.Instant)
+      : queryTypeOptions;
+
+    // if the state's queryType is still Instant, trigger a change to range for log queries
+    if (isLogQuery && queryType === LokiQueryType.Instant) {
+      onChange({ ...query, queryType: LokiQueryType.Range });
+      queryType = LokiQueryType.Range;
+    }
 
     const isValidStep = useMemo(() => {
       if (!query.step || isValidGrafanaDuration(query.step) || !isNaN(Number(query.step))) {
@@ -96,9 +105,11 @@ export const LokiQueryBuilderOptions = React.memo<Props>(
               onCommitChange={onLegendFormatChanged}
             />
           </EditorField>
-          <EditorField label="Type">
-            <RadioButtonGroup options={queryTypeOptions} value={queryType} onChange={onQueryTypeChange} />
-          </EditorField>
+          {filteredQueryTypeOptions.length > 1 && (
+            <EditorField label="Type">
+              <RadioButtonGroup options={filteredQueryTypeOptions} value={queryType} onChange={onQueryTypeChange} />
+            </EditorField>
+          )}
           {isLogQuery && (
             <EditorField label="Line limit" tooltip="Upper limit for number of log lines returned by query.">
               <AutoSizeInput