feat(cache): extend release notes cache TTL (#7596)

Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

lib/workers/pr/changelog/release-notes.spec.ts

@@ -1,4 +1,5 @@
 import fs from 'fs-extra';
+import { DateTime } from 'luxon';
 import * as httpMock from '../../../../test/httpMock';
 import { getName } from '../../../../test/util';
 import { ChangeLogNotes } from './common';
@@ -7,6 +8,7 @@ import {
   getReleaseList,
   getReleaseNotes,
   getReleaseNotesMd,
+  releaseNotesCacheMinutes,
 } from './release-notes';
 
 const angularJsChangelogMd = fs.readFileSync(
@@ -61,6 +63,24 @@ describe(getName(__filename), () => {
     httpMock.reset();
   });
 
+  describe('releaseNotesCacheMinutes', () => {
+    const now = DateTime.local();
+    it.each([
+      [now, 55],
+      [now.minus({ week: 2 }), 1435],
+      [now.minus({ year: 1 }), 14495],
+    ])('works with string date (%s, %i)', (date, minutes) => {
+      expect(releaseNotesCacheMinutes(date?.toISO())).toEqual(minutes);
+    });
+
+    it('handles date object', () => {
+      expect(releaseNotesCacheMinutes(new Date())).toEqual(55);
+    });
+    it.each([null, undefined, 'fake', 123])('handles invalid: %s', (date) => {
+      expect(releaseNotesCacheMinutes(date as never)).toEqual(55);
+    });
+  });
+
   describe('addReleaseNotes()', () => {
     it('returns input if invalid', async () => {
       const input = { a: 1 };

lib/workers/pr/changelog/release-notes.ts

@@ -1,5 +1,7 @@
 import * as URL from 'url';
+import is from '@sindresorhus/is';
 import { linkify } from 'linkify-markdown';
+import { DateTime } from 'luxon';
 import MarkdownIt from 'markdown-it';
 
 import { logger } from '../../../logger';
@@ -260,6 +262,31 @@ export async function getReleaseNotesMd(
   return null;
 }
 
+/**
+ * Determine how long to cache release notes based on when the version was released.
+ *
+ * It's not uncommon for release notes to be updated shortly after the release itself,
+ * so only cache for about an hour when the release is less than a week old. Otherwise,
+ * cache for days.
+ */
+export function releaseNotesCacheMinutes(releaseDate?: string | Date): number {
+  const dt = is.date(releaseDate)
+    ? DateTime.fromJSDate(releaseDate)
+    : DateTime.fromISO(releaseDate);
+
+  const now = DateTime.local();
+
+  if (!dt.isValid || now.diff(dt, 'days').days < 7) {
+    return 55;
+  }
+
+  if (now.diff(dt, 'months').months < 6) {
+    return 1435; // 5 minutes shy of one day
+  }
+
+  return 14495; // 5 minutes shy of 10 days
+}
+
 export async function addReleaseNotes(
   input: ChangeLogResult
 ): Promise<ChangeLogResult> {
@@ -285,22 +312,15 @@ export async function addReleaseNotes(
     let releaseNotes: ChangeLogNotes;
     const cacheKey = getCacheKey(v.version);
     releaseNotes = await packageCache.get(cacheNamespace, cacheKey);
+    // istanbul ignore else: no cache tests
     if (!releaseNotes) {
-      if (input.project.github != null) {
       releaseNotes = await getReleaseNotesMd(
         repository,
         v.version,
         input.project.baseUrl,
         input.project.apiBaseUrl
       );
-      } else {
-        releaseNotes = await getReleaseNotesMd(
-          repository,
-          v.version,
-          input.project.baseUrl,
-          input.project.apiBaseUrl
-        );
-      }
+      // istanbul ignore else: should be tested
       if (!releaseNotes) {
         releaseNotes = await getReleaseNotes(
           repository,
@@ -314,7 +334,7 @@ export async function addReleaseNotes(
       if (!releaseNotes && v.compare.url) {
         releaseNotes = { url: v.compare.url };
       }
-      const cacheMinutes = 55;
+      const cacheMinutes = releaseNotesCacheMinutes(v.date);
       await packageCache.set(
         cacheNamespace,
         cacheKey,