Loki: add support for resolution (#36710)

* Add input to specify min step

* Add stepInterval to as input to component

* Add onBlur to Input component

* Loki: add functionality for min step

* Loki: change name on props to step to make it more clear

* Loki: add resolution as a query option

* Loki: Add min,max,exact as step options

* Loki: add functionality for different step modes

* Loki: fix bug where step function isn't working

* Loki: fix bug where exact step isn't working

* Loki: change width of step input field

* Loki: add tests for adjustInterval function

* Loki: add check for max step oprio to make sure it's not below the safe interval

* Loki: fix bug with some tests

* Loki: fix bug with tests

* Explore: add tooltip to loki step function

* Loki: remove resolution as a logs option

* Loki: update snapshots

* Fix failing tests

* Loki: add select component for choosing resolution

* Loki: add functionality for calculating correct interval with resolution applied

* Loki: remove functionality for step mode

* Loki: remove tests for step mode

* Loki: add tooltip to line limit and resolution

* Loki: add backend support for resolution

* Loki: fixed backend bug where resolution was undefined

* Loki: add check for resolution

CHANGELOG.md

@@ -1,12 +1,11 @@
-
 <!-- 8.1.1 START -->
 
 # 8.1.1 (2021-08-09)
 
 ### Bug fixes
 
-* **CloudWatch Logs:** Fix crash when no region is selected. [#37639](https://github.com/grafana/grafana/pull/37639), [@aocenas](https://github.com/aocenas)
+- **CloudWatch Logs:** Fix crash when no region is selected. [#37639](https://github.com/grafana/grafana/pull/37639), [@aocenas](https://github.com/aocenas)
-* **Reporting:** Fix timezone parsing for scheduler (enterprise)
+- **Reporting:** Fix timezone parsing for scheduler (enterprise)
 
 <!-- 8.1.1 END -->
 <!-- 8.1.0 START -->

docs/sources/datasources/alertmanager.md

@@ -10,7 +10,7 @@ weight = 150
 
 Grafana includes built-in support for Prometheus Alertmanager. It is presently in alpha and not accessible unless [alpha plugins are enabled in Grafana settings](https://grafana.com/docs/grafana/latest/administration/configuration/#enable_alpha). Once you add it as a data source, you can use the [Grafana alerting UI](https://grafana.com/docs/grafana/latest/alerting/) to manage silences, contact points as well as notification policies. A drop down option in these pages allows you to switch between Grafana and any configured Alertmanager data sources .
 
-> **Note:** Currently, the [Cortex implementation of Prometheus Alertmanager](https://cortexmetrics.io/docs/proposals/scalable-alertmanager/) is required to edit rules. 
+> **Note:** Currently, the [Cortex implementation of Prometheus Alertmanager](https://cortexmetrics.io/docs/proposals/scalable-alertmanager/) is required to edit rules.
 
 ## Provision the Alertmanager data source
 

docs/sources/http_api/access_control.md

@@ -26,7 +26,6 @@ Returns an indicator to check if fine-grained access control is enabled or not.
 | -------------------- | ---------------------- |
 | status:accesscontrol | services:accesscontrol |
 
-
 #### Example request
 
 ```http
@@ -256,7 +255,6 @@ Content-Type: application/json; charset=UTF-8
 | action     | string    | Yes      | Refer to [Permissions]({{< relref "../enterprise/access-control/permissions.md" >}}) for full list of available actions.                                                                             |
 | scope      | string    | No       | If not present, no scope will be mapped to the permission. Refer to [Permissions]({{< relref "../enterprise/access-control/permissions.md#scope-definitions" >}}) for full list of available scopes. |
 
-| scope      | string    | No       | If not present, no scope will be mapped to the permission. Refer to [Permissions]({{< relref "../enterprise/access-control/permissions.md#scope-definitions" >}}) for full list of available scopes. |
 #### Example response
 
 ```http
@@ -279,7 +277,6 @@ For example, if a user does not have required permissions for creating users, th
 
 `DELETE /api/access-control/roles/:uid?force=false`
 
-
 Delete a role with the given UID, and it's permissions. If the role is assigned to a built-in role, the deletion operation will fail, unless `force` query param is set to `true`, and in that case all assignments will also be deleted.
 
 #### Required permissions
@@ -377,7 +374,6 @@ For example, if a user does not have required permissions for creating users, th
 | roles.builtin:add | permissions:delegate |
 
 #### Example request
-#### Example request
 
 ```http
 POST /api/access-control/builtin-roles

docs/sources/release-notes/release-notes-8-1-1.md

@@ -10,5 +10,4 @@ list = false
 
 ### Bug fixes
 
-* **CloudWatch Logs:** Fix crash when no region is selected. [#37639](https://github.com/grafana/grafana/pull/37639), [@aocenas](https://github.com/aocenas)
+- **CloudWatch Logs:** Fix crash when no region is selected. [#37639](https://github.com/grafana/grafana/pull/37639), [@aocenas](https://github.com/aocenas)
-

pkg/tsdb/loki/loki.go

@@ -56,6 +56,7 @@ type ResponseModel struct {
 	LegendFormat string `json:"legendFormat"`
 	Interval     string `json:"interval"`
 	IntervalMS   int    `json:"intervalMS"`
+	Resolution   int64  `json:"resolution"`
 }
 
 func init() {
@@ -210,7 +211,12 @@ func (s *Service) parseQuery(dsInfo *datasourceInfo, queryContext *backend.Query
 			return nil, err
 		}
 
-		step := time.Duration(int64(interval.Value))
+		var resolution int64 = 1
+		if model.Resolution >= 1 && model.Resolution <= 5 || model.Resolution == 10 {
+			resolution = model.Resolution
+		}
+
+		step := time.Duration(int64(interval.Value) * resolution)
 
 		qs = append(qs, &lokiQuery{
 			Expr:         model.Expr,

public/app/plugins/datasource/loki/components/AnnotationsQueryEditor.tsx

@@ -36,6 +36,7 @@ export const LokiAnnotationsQueryEditor = memo(function LokiAnnotationQueryEdito
           <LokiOptionFields
             queryType={queryWithRefId.instant ? 'instant' : 'range'}
             lineLimitValue={queryWithRefId?.maxLines?.toString() || ''}
+            resolution={queryWithRefId.resolution || 1}
             query={queryWithRefId}
             onRunQuery={() => {}}
             onChange={onChange}

public/app/plugins/datasource/loki/components/LokiExploreQueryEditor.tsx

@@ -27,6 +27,7 @@ export function LokiExploreQueryEditor(props: Props) {
         <LokiOptionFields
           queryType={query.instant ? 'instant' : 'range'}
           lineLimitValue={query?.maxLines?.toString() || ''}
+          resolution={query.resolution || 1}
           query={query}
           onRunQuery={onRunQuery}
           onChange={onChange}

public/app/plugins/datasource/loki/components/LokiOptionFields.tsx

@@ -1,14 +1,16 @@
 // Libraries
 import React, { memo } from 'react';
 import { css, cx } from '@emotion/css';
-import { LokiQuery } from '../types';
+import { map } from 'lodash';
-import { SelectableValue } from '@grafana/data';
 
 // Types
-import { InlineFormLabel, RadioButtonGroup, InlineField, Input } from '@grafana/ui';
+import { InlineFormLabel, RadioButtonGroup, InlineField, Input, Select } from '@grafana/ui';
+import { SelectableValue } from '@grafana/data';
+import { LokiQuery } from '../types';
 
 export interface LokiOptionFieldsProps {
   lineLimitValue: string;
+  resolution: number;
   queryType: LokiQueryType;
   query: LokiQuery;
   onChange: (value: LokiQuery) => void;
@@ -27,8 +29,20 @@ const queryTypeOptions: Array<SelectableValue<LokiQueryType>> = [
   },
 ];
 
+export const DEFAULT_RESOLUTION: SelectableValue<number> = {
+  value: 1,
+  label: '1/1',
+};
+
+const RESOLUTION_OPTIONS: Array<SelectableValue<number>> = [DEFAULT_RESOLUTION].concat(
+  map([2, 3, 4, 5, 10], (value: number) => ({
+    value,
+    label: '1/' + value,
+  }))
+);
+
 export function LokiOptionFields(props: LokiOptionFieldsProps) {
-  const { lineLimitValue, queryType, query, onRunQuery, runOnBlur, onChange } = props;
+  const { lineLimitValue, resolution, queryType, query, onRunQuery, runOnBlur, onChange } = props;
 
   function onChangeQueryLimit(value: string) {
     const nextQuery = { ...query, maxLines: preprocessMaxLines(value) };
@@ -71,6 +85,11 @@ export function LokiOptionFields(props: LokiOptionFieldsProps) {
     }
   }
 
+  function onResolutionChange(option: SelectableValue<number>) {
+    const nextQuery = { ...query, resolution: option.value };
+    onChange(nextQuery);
+  }
+
   return (
     <div aria-label="Loki extra field" className="gf-form-inline">
       {/*Query type field*/}
@@ -108,7 +127,7 @@ export function LokiOptionFields(props: LokiOptionFieldsProps) {
         )}
         aria-label="Line limit field"
       >
-        <InlineField label="Line limit">
+        <InlineField label="Line limit" tooltip={'Upper limit for number of log lines returned by query.'}>
           <Input
             className="width-4"
             placeholder="auto"
@@ -124,6 +143,14 @@ export function LokiOptionFields(props: LokiOptionFieldsProps) {
             }}
           />
         </InlineField>
+        <InlineField
+          label="Resolution"
+          tooltip={
+            'Resolution 1/1 sets step parameter of Loki metrics range queries such that each pixel corresponds to one data point. For better performance, lower resolutions can be picked. 1/2 only retrieves a data point for every other pixel, and 1/10 retrieves one data point per 10 pixels.'
+          }
+        >
+          <Select isSearchable={false} onChange={onResolutionChange} options={RESOLUTION_OPTIONS} value={resolution} />
+        </InlineField>
       </div>
     </div>
   );

public/app/plugins/datasource/loki/components/LokiQueryEditor.tsx

@@ -53,6 +53,7 @@ export function LokiQueryEditor(props: LokiQueryEditorProps) {
           <LokiOptionFields
             queryType={query.instant ? 'instant' : 'range'}
             lineLimitValue={query?.maxLines?.toString() || ''}
+            resolution={query?.resolution || 1}
             query={query}
             onRunQuery={onRunQuery}
             onChange={onChange}

public/app/plugins/datasource/loki/components/__snapshots__/LokiExploreQueryEditor.test.tsx.snap

@@ -15,6 +15,7 @@ exports[`LokiExploreQueryEditor should render component 1`] = `
         }
       }
       queryType="range"
+      resolution={1}
     />
   }
   data={

public/app/plugins/datasource/loki/components/__snapshots__/LokiQueryEditor.test.tsx.snap

@@ -16,6 +16,7 @@ exports[`Render LokiQueryEditor with legend should render 1`] = `
           }
         }
         queryType="range"
+        resolution={1}
         runOnBlur={true}
       />
       <div
@@ -81,6 +82,7 @@ exports[`Render LokiQueryEditor with legend should update timerange 1`] = `
           }
         }
         queryType="range"
+        resolution={1}
         runOnBlur={true}
       />
       <div

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

@@ -112,7 +112,7 @@ describe('LokiDatasource', () => {
       const req = ds.createRangeQuery(target, options as any, 1000);
       expect(req.start).toBeDefined();
       expect(req.end).toBeDefined();
-      expect(adjustIntervalSpy).toHaveBeenCalledWith(1000, expect.anything());
+      expect(adjustIntervalSpy).toHaveBeenCalledWith(1000, 1, expect.anything());
     });
 
     it('should use provided intervalMs', () => {
@@ -127,7 +127,7 @@ describe('LokiDatasource', () => {
       const req = ds.createRangeQuery(target, options as any, 1000);
       expect(req.start).toBeDefined();
       expect(req.end).toBeDefined();
-      expect(adjustIntervalSpy).toHaveBeenCalledWith(2000, expect.anything());
+      expect(adjustIntervalSpy).toHaveBeenCalledWith(2000, 1, expect.anything());
     });
 
     it('should set the minimal step to 1ms', () => {
@@ -142,7 +142,7 @@ describe('LokiDatasource', () => {
       const req = ds.createRangeQuery(target, options as any, 1000);
       expect(req.start).toBeDefined();
       expect(req.end).toBeDefined();
-      expect(adjustIntervalSpy).toHaveBeenCalledWith(0.0005, expect.anything());
+      expect(adjustIntervalSpy).toHaveBeenCalledWith(0.0005, expect.anything(), 1000);
       // Step is in seconds (1 ms === 0.001 s)
       expect(req.step).toEqual(0.001);
     });
@@ -399,7 +399,7 @@ describe('LokiDatasource', () => {
 
     describe('__range, __range_s and __range_ms variables', () => {
       const options = {
-        targets: [{ expr: 'rate(process_cpu_seconds_total[$__range])', refId: 'A' }],
+        targets: [{ expr: 'rate(process_cpu_seconds_total[$__range])', refId: 'A', stepInterval: '2s' }],
         range: {
           from: rawRange.from,
           to: rawRange.to,
@@ -581,7 +581,7 @@ describe('LokiDatasource', () => {
           status: 'success',
         },
       } as unknown) as FetchResponse;
-      const { promise } = getTestContext(response);
+      const { promise } = getTestContext(response, { stepInterval: '15s' });
 
       const res = await promise;
 
@@ -613,7 +613,7 @@ describe('LokiDatasource', () => {
       } as unknown) as FetchResponse;
       describe('When tagKeys is set', () => {
         it('should only include selected labels', async () => {
-          const { promise } = getTestContext(response, { tagKeys: 'label2,label3' });
+          const { promise } = getTestContext(response, { tagKeys: 'label2,label3', stepInterval: '15s' });
 
           const res = await promise;
 
@@ -624,7 +624,7 @@ describe('LokiDatasource', () => {
       });
       describe('When textFormat is set', () => {
         it('should fromat the text accordingly', async () => {
-          const { promise } = getTestContext(response, { textFormat: 'hello {{label2}}' });
+          const { promise } = getTestContext(response, { textFormat: 'hello {{label2}}', stepInterval: '15s' });
 
           const res = await promise;
 
@@ -634,7 +634,7 @@ describe('LokiDatasource', () => {
       });
       describe('When titleFormat is set', () => {
         it('should fromat the title accordingly', async () => {
-          const { promise } = getTestContext(response, { titleFormat: 'Title {{label2}}' });
+          const { promise } = getTestContext(response, { titleFormat: 'Title {{label2}}', stepInterval: '15s' });
 
           const res = await promise;
 
@@ -781,6 +781,26 @@ describe('LokiDatasource', () => {
       });
     });
   });
+
+  describe('adjustInterval', () => {
+    const dynamicInterval = 15;
+    const range = 1642;
+    const resolution = 1;
+    const ds = createLokiDSForTests();
+    it('should return the interval as a factor of dynamicInterval and resolution', () => {
+      let interval = ds.adjustInterval(dynamicInterval, resolution, range);
+      expect(interval).toBe(resolution * dynamicInterval);
+    });
+    it('should not return a value less than the safe interval', () => {
+      let safeInterval = range / 11000;
+      if (safeInterval > 1) {
+        safeInterval = Math.ceil(safeInterval);
+      }
+      const unsafeInterval = safeInterval - 0.01;
+      let interval = ds.adjustInterval(unsafeInterval, resolution, range);
+      expect(interval).toBeGreaterThanOrEqual(safeInterval);
+    });
+  });
 });
 
 function createLokiDSForTests(

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

@@ -51,6 +51,7 @@ import LanguageProvider from './language_provider';
 import { serializeParams } from '../../../core/utils/fetch';
 import { RowContextOptions } from '@grafana/ui/src/components/Logs/LogRowContextProvider';
 import syntax from './syntax';
+import { DEFAULT_RESOLUTION } from './components/LokiOptionFields';
 
 export type RangeQueryOptions = DataQueryRequest<LokiQuery> | AnnotationQueryRequest<LokiQuery>;
 export const DEFAULT_MAX_LINES = 1000;
@@ -186,8 +187,11 @@ export class LokiDatasource extends DataSourceApi<LokiQuery, LokiOptions> {
       const startNs = this.getTime(options.range.from, false);
       const endNs = this.getTime(options.range.to, true);
       const rangeMs = Math.ceil((endNs - startNs) / 1e6);
+
+      const resolution = target.resolution || (DEFAULT_RESOLUTION.value as number);
+
       const adjustedInterval =
-        this.adjustInterval((options as DataQueryRequest<LokiQuery>).intervalMs || 1000, rangeMs) / 1000;
+        this.adjustInterval((options as DataQueryRequest<LokiQuery>).intervalMs || 1000, resolution, rangeMs) / 1000;
       // We want to ceil to 3 decimal places
       const step = Math.ceil(adjustedInterval * 1000) / 1000;
 
@@ -558,14 +562,28 @@ export class LokiDatasource extends DataSourceApi<LokiQuery, LokiOptions> {
   }
 
   async annotationQuery(options: any): Promise<AnnotationEvent[]> {
-    const { expr, maxLines, instant, tagKeys = '', titleFormat = '', textFormat = '' } = options.annotation;
+    const {
+      expr,
+      maxLines,
+      instant,
+      stepInterval,
+      tagKeys = '',
+      titleFormat = '',
+      textFormat = '',
+    } = options.annotation;
 
     if (!expr) {
       return [];
     }
 
     const interpolatedExpr = this.templateSrv.replace(expr, {}, this.interpolateQueryExpr);
-    const query = { refId: `annotation-${options.annotation.name}`, expr: interpolatedExpr, maxLines, instant };
+    const query = {
+      refId: `annotation-${options.annotation.name}`,
+      expr: interpolatedExpr,
+      maxLines,
+      instant,
+      stepInterval,
+    };
     const { data } = instant
       ? await this.runInstantQuery(query, options as any).toPromise()
       : await this.runRangeQuery(query, options as any).toPromise();
@@ -634,14 +652,16 @@ export class LokiDatasource extends DataSourceApi<LokiQuery, LokiOptions> {
     return error;
   }
 
-  adjustInterval(interval: number, range: number) {
+  adjustInterval(dynamicInterval: number, resolution: number, range: number) {
     // Loki will drop queries that might return more than 11000 data points.
     // Calibrate interval if it is too small.
-    if (interval !== 0 && range / interval > 11000) {
+    let safeInterval = range / 11000;
-      interval = Math.ceil(range / 11000);
+    if (safeInterval > 1) {
+      safeInterval = Math.ceil(safeInterval);
     }
-    // The min interval is set to 1ms
+
-    return Math.max(interval, 1);
+    let adjustedInterval = Math.max(resolution * dynamicInterval, safeInterval);
+    return adjustedInterval;
   }
 
   addAdHocFilters(queryExpr: string) {

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

@@ -30,6 +30,7 @@ export interface LokiQuery extends DataQuery {
   legendFormat?: string;
   valueWithRefId?: boolean;
   maxLines?: number;
+  resolution?: number;
   range?: boolean;
   instant?: boolean;
 }