refactor: cache changelog per-release

Closes #2473

lib/workers/pr/changelog/index.js

@@ -6,13 +6,6 @@ module.exports = {
   getChangeLogJSON,
 };
 
-const cacheNamespace = 'changelog';
-function getCacheKey({ repositoryUrl, releases }) {
-  return `${repositoryUrl}-${
-    releases ? releases.map(release => release.version).join('-') : ''
-  }`;
-}
-
 async function getChangeLogJSON(args) {
   const { repositoryUrl, versionScheme, fromVersion, toVersion } = args;
   if (!repositoryUrl) {
@@ -25,23 +18,8 @@ async function getChangeLogJSON(args) {
   if (!fromVersion || equals(fromVersion, toVersion)) {
     return null;
   }
-  const cachedResult = await renovateCache.get(
-    cacheNamespace,
-    getCacheKey(args)
-  );
-  if (cachedResult) {
-    return cachedResult;
-  }
-
   try {
     const res = await sourceGithub.getChangeLogJSON({ ...args });
-    const cacheMinutes = 60;
-    await renovateCache.set(
-      cacheNamespace,
-      getCacheKey(args),
-      res,
-      cacheMinutes
-    );
     return res;
   } catch (err) /* istanbul ignore next */ {
     logger.error(

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

@@ -182,8 +182,16 @@ async function addReleaseNotes(input) {
   }
   const output = { ...input, versions: [] };
   const repository = input.project.github.replace(/\.git$/, '');
+  const cacheNamespace = 'changelog-github-notes';
+  function getCacheKey(version) {
+    return `${repository}:${version}`;
+  }
   for (const v of input.versions) {
-    let releaseNotes = await getReleaseNotesMd(
+    let releaseNotes;
+    const cacheKey = getCacheKey(v.version);
+    releaseNotes = await renovateCache.get(cacheNamespace, cacheKey);
+    if (!releaseNotes) {
+      releaseNotes = await getReleaseNotesMd(
         repository,
         v.version,
         input.project.githubBaseURL
@@ -200,6 +208,14 @@ async function addReleaseNotes(input) {
       if (!releaseNotes && v.compare.url) {
         releaseNotes = { url: v.compare.url };
       }
+      const cacheMinutes = 30;
+      await renovateCache.set(
+        cacheNamespace,
+        cacheKey,
+        releaseNotes,
+        cacheMinutes
+      );
+    }
     output.versions.push({
       ...v,
       releaseNotes,

lib/workers/pr/changelog/source-github.js

@@ -108,6 +108,11 @@ async function getChangeLogJSON({
     return getDateRef(config.endpoint, repository, release.releaseTimestamp);
   }
 
+  const cacheNamespace = 'changelog-github-release';
+  function getCacheKey(version) {
+    return `${repository}:${version}`;
+  }
+
   const changelogReleases = [];
   // compare versions
   const include = version =>
@@ -116,7 +121,12 @@ async function getChangeLogJSON({
     const prev = validReleases[i - 1];
     const next = validReleases[i];
     if (include(next.version)) {
-      const release = {
+      let release = await renovateCache.get(
+        cacheNamespace,
+        getCacheKey(next.version)
+      );
+      if (!release) {
+        release = {
           version: next.version,
           date: next.releaseTimestamp,
           // put empty changes so that existing templates won't break
@@ -128,6 +138,14 @@ async function getChangeLogJSON({
         if (prevHead && nextHead) {
           release.compare.url = `${githubBaseURL}${repository}/compare/${prevHead}...${nextHead}`;
         }
+        const cacheMinutes = 30;
+        await renovateCache.set(
+          cacheNamespace,
+          getCacheKey(next.version),
+          release,
+          cacheMinutes
+        );
+      }
       changelogReleases.unshift(release);
     }
   }

test/workers/pr/changelog/__snapshots__/index.spec.js.snap

@@ -163,12 +163,14 @@ Object {
     Object {
       "changes": Array [],
       "compare": Object {},
+      "releaseNotes": undefined,
       "version": "2.5.2",
     },
     Object {
       "changes": Array [],
       "compare": Object {},
       "date": "2017-12-24T03:20:46.238Z",
+      "releaseNotes": undefined,
       "version": "2.4.2",
     },
     Object {