[8.8] feat(slo): simplify calendar aligned time window (#157759) (#15…

…7789)

# Backport

This will backport the following commits from `main` to `8.8`:
- [feat(slo): simplify calendar aligned time window
(#157759)](#157759)

<!--- Backport version: 8.9.7 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

<!--BACKPORT [{"author":{"name":"Kevin
Delemme","email":"kevin.delemme@elastic.co"},"sourceCommit":{"committedDate":"2023-05-15T18:59:36Z","message":"feat(slo):
simplify calendar aligned time window
(#157759)","sha":"e5f4dca5557a9d25acfd2ec2632aa3f35cd3732e","branchLabelMapping":{"^v8.9.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["release_note:skip","Team:
Actionable
Observability","backport:prev-minor","v8.9.0"],"number":157759,"url":"https://github.com/elastic/kibana/pull/157759","mergeCommit":{"message":"feat(slo):
simplify calendar aligned time window
(#157759)","sha":"e5f4dca5557a9d25acfd2ec2632aa3f35cd3732e"}},"sourceBranch":"main","suggestedTargetBranches":[],"targetPullRequestStates":[{"branch":"main","label":"v8.9.0","labelRegex":"^v8.9.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/157759","number":157759,"mergeCommit":{"message":"feat(slo):
simplify calendar aligned time window
(#157759)","sha":"e5f4dca5557a9d25acfd2ec2632aa3f35cd3732e"}}]}]
BACKPORT-->

Co-authored-by: Kevin Delemme <kevin.delemme@elastic.co>

packages/kbn-slo-schema/src/schema/time_window.ts

@@ -7,7 +7,6 @@
  */
 
 import * as t from 'io-ts';
-import { dateType } from './common';
 import { durationType } from './duration';
 
 const rollingTimeWindowSchema = t.type({
@@ -17,7 +16,7 @@ const rollingTimeWindowSchema = t.type({
 
 const calendarAlignedTimeWindowSchema = t.type({
   duration: durationType,
-  calendar: t.type({ startTime: dateType }),
+  isCalendar: t.literal<boolean>(true),
 });
 
 const timeWindowSchema = t.union([rollingTimeWindowSchema, calendarAlignedTimeWindowSchema]);

x-pack/plugins/observability/docs/openapi/slo/bundled.yaml

@@ -503,22 +503,18 @@ components:
       title: Calendar aligned time window definition
       required:
         - duration
-        - calendar
+        - isCalendar
       description: Defines properties for calendar aligned time window
       type: object
       properties:
         duration:
-          description: the duration formatted as {duration}{unit}
+          description: the duration formatted as {duration}{unit}, accept '1w' (weekly calendar) or '1M' (monthly calendar) only
           type: string
           example: 1M
-        calendar:
-          description: Defines the calendar start date
-          type: object
-          properties:
-            startTime:
-              description: The start date to use.
-              type: string
-              example: '2022-01-01T08:00:00.000Z'
+        isCalendar:
+          description: Indicates a calendar aligned time window
+          type: boolean
+          example: true
     budgeting_method:
       title: Budgeting method
       type: string

x-pack/plugins/observability/docs/openapi/slo/components/schemas/time_window_calendar_aligned.yaml

@@ -1,19 +1,15 @@
 title: Calendar aligned time window definition
 required:
   - duration
-  - calendar
+  - isCalendar
 description: Defines properties for calendar aligned time window
 type: object
 properties:
   duration:
-    description: the duration formatted as {duration}{unit}
+    description: the duration formatted as {duration}{unit}, accept '1w' (weekly calendar) or '1M' (monthly calendar) only
     type: string
     example: 1M
-  calendar:
-    description: Defines the calendar start date
-    type: object
-    properties:
-      startTime:
-        description: The start date to use.
-        type: string
-        example: "2022-01-01T08:00:00.000Z"
+  isCalendar:
+    description: Indicates a calendar aligned time window
+    type: boolean
+    example: true

x-pack/plugins/observability/public/components/slo/slo_status_badge/slo_status_badge.tsx

@@ -50,15 +50,14 @@ export function SloStatusBadge({ slo }: SloStatusProps) {
           </EuiBadge>
         )}
       </EuiFlexItem>
+
       {slo.summary.errorBudget.isEstimated && (
         <EuiFlexItem grow={false}>
-          <div>
-            <EuiBadge color="default">
-              {i18n.translate('xpack.observability.slo.sloStatusBadge.forecasted', {
-                defaultMessage: 'Forecasted',
-              })}
-            </EuiBadge>
-          </div>
+          <EuiBadge color="default">
+            {i18n.translate('xpack.observability.slo.sloStatusBadge.forecasted', {
+              defaultMessage: 'Forecasted',
+            })}
+          </EuiBadge>
         </EuiFlexItem>
       )}
     </>

x-pack/plugins/observability/public/data/slo/time_window.ts

@@ -22,7 +22,7 @@ export const buildCalendarAlignedTimeWindow = (
 ): SLOWithSummaryResponse['timeWindow'] => {
   return {
     duration: '1M',
-    calendar: { startTime: '2023-01-01T00:00:00.000Z' },
+    isCalendar: true,
     ...params,
   };
 };

x-pack/plugins/observability/public/pages/slos/components/badges/slo_time_window_badge.stories.tsx

@@ -31,30 +31,16 @@ With7DaysRolling.args = { slo: buildSlo({ timeWindow: { duration: '7d', isRollin
 export const With30DaysRolling = Template.bind({});
 With30DaysRolling.args = { slo: buildSlo({ timeWindow: { duration: '30d', isRolling: true } }) };
 
-export const WithMonthlyCalendarStartingToday = Template.bind({});
-WithMonthlyCalendarStartingToday.args = {
+export const WithWeeklyCalendar = Template.bind({});
+WithWeeklyCalendar.args = {
   slo: buildSlo({
-    timeWindow: { duration: '1M', calendar: { startTime: new Date().toISOString() } },
+    timeWindow: { duration: '1w', isCalendar: true },
   }),
 };
 
 export const WithMonthlyCalendar = Template.bind({});
 WithMonthlyCalendar.args = {
   slo: buildSlo({
-    timeWindow: { duration: '1M', calendar: { startTime: '2022-01-01T00:00:00.000Z' } },
-  }),
-};
-
-export const WithBiWeeklyCalendar = Template.bind({});
-WithBiWeeklyCalendar.args = {
-  slo: buildSlo({
-    timeWindow: { duration: '2w', calendar: { startTime: '2023-01-01T00:00:00.000Z' } },
-  }),
-};
-
-export const WithQuarterlyCalendar = Template.bind({});
-WithQuarterlyCalendar.args = {
-  slo: buildSlo({
-    timeWindow: { duration: '1Q', calendar: { startTime: '2022-01-01T00:00:00.000Z' } },
+    timeWindow: { duration: '1M', isCalendar: true },
   }),
 };

x-pack/plugins/observability/public/pages/slos/components/badges/slo_time_window_badge.tsx

@@ -20,7 +20,6 @@ export interface Props {
 }
 
 export function SloTimeWindowBadge({ slo }: Props) {
-  const duration = Number(slo.timeWindow.duration.slice(0, -1));
   const unit = slo.timeWindow.duration.slice(-1);
   if ('isRolling' in slo.timeWindow) {
     return (
@@ -38,15 +37,11 @@ export function SloTimeWindowBadge({ slo }: Props) {
 
   const unitMoment = toMomentUnitOfTime(unit);
   const now = moment.utc();
-  const startTime = moment.utc(slo.timeWindow.calendar.startTime);
-  const differenceInUnit = now.diff(startTime, unitMoment);
 
-  const periodStart = startTime
-    .clone()
-    .add(Math.floor(differenceInUnit / duration) * duration, unitMoment);
-  const periodEnd = periodStart.clone().add(duration, unitMoment);
+  const periodStart = now.clone().startOf(unitMoment!);
+  const periodEnd = now.clone().endOf(unitMoment!);
 
-  const totalDurationInDays = periodEnd.diff(periodStart, 'days');
+  const totalDurationInDays = periodEnd.diff(periodStart, 'days') + 1;
   const elapsedDurationInDays = now.diff(periodStart, 'days') + 1;
 
   return (

x-pack/plugins/observability/server/domain/services/compute_error_budget.test.ts

@@ -5,7 +5,6 @@
  * 2.0.
  */
 
-import { twoDaysAgo } from '../../services/slo/fixtures/date';
 import { oneMinute } from '../../services/slo/fixtures/duration';
 import { createSLO } from '../../services/slo/fixtures/slo';
 import { sevenDaysRolling, weeklyCalendarAligned } from '../../services/slo/fixtures/time_window';
@@ -64,10 +63,14 @@ describe('computeErrorBudget', () => {
 
   describe('for calendar aligned time window', () => {
     describe('for occurrences budgeting method', () => {
+      beforeEach(() => {
+        jest.useFakeTimers({ now: new Date('2023-05-09') });
+      });
+
       it('computes the error budget with an estimation of total events', () => {
         const slo = createSLO({
           budgetingMethod: 'occurrences',
-          timeWindow: weeklyCalendarAligned(twoDaysAgo()),
+          timeWindow: weeklyCalendarAligned(),
           objective: { target: 0.95 },
         });
         const dateRange = toDateRange(slo.timeWindow);
@@ -90,7 +93,7 @@ describe('computeErrorBudget', () => {
       it('computes the error budget', () => {
         const slo = createSLO({
           budgetingMethod: 'timeslices',
-          timeWindow: weeklyCalendarAligned(twoDaysAgo()),
+          timeWindow: weeklyCalendarAligned(),
           objective: { target: 0.95, timesliceTarget: 0.95, timesliceWindow: oneMinute() },
         });
         const dateRange = toDateRange(slo.timeWindow);
@@ -106,8 +109,8 @@ describe('computeErrorBudget', () => {
         // consumed = error rate / error budget = 0.00565476 / 0.05 = 0.1130952
         expect(errorBudget).toEqual({
           initial: 0.05,
-          consumed: 0.113095,
-          remaining: 0.886905,
+          consumed: 0.113106,
+          remaining: 0.886894,
           isEstimated: false,
         });
       });

x-pack/plugins/observability/server/domain/services/date_range.test.ts

@@ -8,97 +8,25 @@
 import { TimeWindow } from '../models/time_window';
 import { Duration } from '../models';
 import { toDateRange } from './date_range';
-import {
-  oneMonth,
-  oneQuarter,
-  oneWeek,
-  thirtyDays,
-  twoWeeks,
-} from '../../services/slo/fixtures/duration';
+import { oneMonth, oneQuarter, oneWeek, thirtyDays } from '../../services/slo/fixtures/duration';
 
 const NOW = new Date('2022-08-11T08:31:00.000Z');
 
 describe('toDateRange', () => {
   describe('for calendar aligned time window', () => {
-    it('throws when start_time is in the future', () => {
-      const futureDate = new Date();
-      futureDate.setFullYear(futureDate.getFullYear() + 1);
-
-      const timeWindow = aCalendarTimeWindow(oneWeek(), futureDate);
-      expect(() => toDateRange(timeWindow, NOW)).toThrow(
-        'Cannot compute date range with future starting time'
-      );
-    });
-
-    describe("with 'weekly' duration", () => {
-      it('computes the date range when starting the same day', () => {
-        const timeWindow = aCalendarTimeWindow(oneWeek(), new Date('2022-08-11T08:30:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-08-11T08:30:00.000Z'),
-          to: new Date('2022-08-18T08:30:00.000Z'),
-        });
-      });
-
-      it('computes the date range when starting a month ago', () => {
-        const timeWindow = aCalendarTimeWindow(oneWeek(), new Date('2022-07-05T08:00:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-08-09T08:00:00.000Z'),
-          to: new Date('2022-08-16T08:00:00.000Z'),
-        });
+    it('computes the date range for weekly calendar', () => {
+      const timeWindow = aCalendarTimeWindow(oneWeek());
+      expect(toDateRange(timeWindow, NOW)).toEqual({
+        from: new Date('2022-08-07T00:00:00.000Z'),
+        to: new Date('2022-08-13T23:59:59.999Z'),
       });
     });
 
-    describe("with 'bi-weekly' duration", () => {
-      it('computes the date range when starting the same day', () => {
-        const timeWindow = aCalendarTimeWindow(twoWeeks(), new Date('2022-08-11T08:00:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-08-11T08:00:00.000Z'),
-          to: new Date('2022-08-25T08:00:00.000Z'),
-        });
-      });
-
-      it('computes the date range when starting a month ago', () => {
-        const timeWindow = aCalendarTimeWindow(twoWeeks(), new Date('2022-07-05T08:00:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-08-02T08:00:00.000Z'),
-          to: new Date('2022-08-16T08:00:00.000Z'),
-        });
-      });
-    });
-
-    describe("with 'monthly' duration", () => {
-      it('computes the date range when starting the same month', () => {
-        const timeWindow = aCalendarTimeWindow(oneMonth(), new Date('2022-08-01T08:00:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-08-01T08:00:00.000Z'),
-          to: new Date('2022-09-01T08:00:00.000Z'),
-        });
-      });
-
-      it('computes the date range when starting a month ago', () => {
-        const timeWindow = aCalendarTimeWindow(oneMonth(), new Date('2022-07-01T08:00:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-08-01T08:00:00.000Z'),
-          to: new Date('2022-09-01T08:00:00.000Z'),
-        });
-      });
-    });
-
-    describe("with 'quarterly' duration", () => {
-      it('computes the date range when starting the same quarter', () => {
-        const timeWindow = aCalendarTimeWindow(oneQuarter(), new Date('2022-07-01T08:00:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-07-01T08:00:00.000Z'),
-          to: new Date('2022-10-01T08:00:00.000Z'),
-        });
-      });
-
-      it('computes the date range when starting a quarter ago', () => {
-        const timeWindow = aCalendarTimeWindow(oneQuarter(), new Date('2022-03-01T08:00:00.000Z'));
-        expect(toDateRange(timeWindow, NOW)).toEqual({
-          from: new Date('2022-06-01T08:00:00.000Z'),
-          to: new Date('2022-09-01T08:00:00.000Z'),
-        });
+    it('computes the date range for monthly calendar', () => {
+      const timeWindow = aCalendarTimeWindow(oneMonth());
+      expect(toDateRange(timeWindow, NOW)).toEqual({
+        from: new Date('2022-08-01T00:00:00.000Z'),
+        to: new Date('2022-08-31T23:59:59.999Z'),
       });
     });
   });
@@ -134,10 +62,10 @@ describe('toDateRange', () => {
   });
 });
 
-function aCalendarTimeWindow(duration: Duration, startTime: Date): TimeWindow {
+function aCalendarTimeWindow(duration: Duration): TimeWindow {
   return {
     duration,
-    calendar: { startTime },
+    isCalendar: true,
   };
 }
 

x-pack/plugins/observability/server/domain/services/date_range.ts

@@ -8,35 +8,22 @@
 import { assertNever } from '@kbn/std';
 import moment from 'moment';
 import { calendarAlignedTimeWindowSchema, rollingTimeWindowSchema } from '@kbn/slo-schema';
-import { DateRange, toMomentUnitOfTime } from '../models';
 
+import { DateRange, toMomentUnitOfTime } from '../models';
 import type { TimeWindow } from '../models/time_window';
 
 export const toDateRange = (timeWindow: TimeWindow, currentDate: Date = new Date()): DateRange => {
   if (calendarAlignedTimeWindowSchema.is(timeWindow)) {
     const unit = toMomentUnitOfTime(timeWindow.duration.unit);
-    const now = moment.utc(currentDate).startOf('minute');
-    const startTime = moment.utc(timeWindow.calendar.startTime);
-
-    const differenceInUnit = now.diff(startTime, unit);
-    if (differenceInUnit < 0) {
-      throw new Error('Cannot compute date range with future starting time');
-    }
-
-    const from = startTime
-      .clone()
-      .add(
-        Math.floor(differenceInUnit / timeWindow.duration.value) * timeWindow.duration.value,
-        unit
-      );
-    const to = from.clone().add(timeWindow.duration.value, unit);
+    const from = moment.utc(currentDate).startOf(unit);
+    const to = moment.utc(currentDate).endOf(unit);
 
     return { from: from.toDate(), to: to.toDate() };
   }
 
   if (rollingTimeWindowSchema.is(timeWindow)) {
     const unit = toMomentUnitOfTime(timeWindow.duration.unit);
-    const now = moment(currentDate).startOf('minute');
+    const now = moment.utc(currentDate).startOf('minute');
 
     return {
       from: now.clone().subtract(timeWindow.duration.value, unit).toDate(),