Monitor cache saves and add basic caching report

- Restore `CachingReport` instance in 'post' action
- Record keys for any entries saved
- Report caching activity as JSON in post action

__tests__/cache-utils.test.ts

@@ -1,5 +1,4 @@
 import * as cacheUtils from '../src/cache-utils'
-import * as path from 'path'
 
 describe('cacheUtils-utils', () => {
     describe('can hash', () => {
@@ -18,4 +17,97 @@ describe('cacheUtils-utils', () => {
             expect(posixHash).toBe(windowsHash)
         })
     })
+    describe('caching report', () => {
+        describe('reports not fully restored', () => {
+            it('with one requested entry report', async () => {
+                const report = new cacheUtils.CachingReport()
+                report.entryReport('foo').markRequested('1', ['2'])
+                report.entryReport('bar').markRequested('3').markRestored('4')
+                expect(report.fullyRestored).toBe(false)
+            })
+        })
+        describe('reports fully restored', () => {
+            it('when empty', async () => {
+                const report = new cacheUtils.CachingReport()
+                expect(report.fullyRestored).toBe(true)
+            })
+            it('with empty entry reports', async () => {
+                const report = new cacheUtils.CachingReport()
+                report.entryReport('foo')
+                report.entryReport('bar')
+                expect(report.fullyRestored).toBe(true)
+            })
+            it('with restored entry report', async () => {
+                const report = new cacheUtils.CachingReport()
+                report.entryReport('bar').markRequested('3').markRestored('4')
+                expect(report.fullyRestored).toBe(true)
+            })
+            it('with multiple restored entry reportss', async () => {
+                const report = new cacheUtils.CachingReport()
+                report.entryReport('foo').markRestored('4')
+                report.entryReport('bar').markRequested('3').markRestored('4')
+                expect(report.fullyRestored).toBe(true)
+            })
+        })
+        describe('can be stringified and rehydrated', () => {
+            it('when empty', async () => {
+                const report = new cacheUtils.CachingReport()
+
+                const stringRep = report.stringify()
+                const reportClone: cacheUtils.CachingReport = cacheUtils.CachingReport.rehydrate(stringRep)
+
+                expect(reportClone.cacheEntryReports).toEqual([])
+
+                // Can call methods on rehydrated
+                expect(reportClone.entryReport('foo')).toBeInstanceOf(cacheUtils.CacheEntryReport)
+            })
+            it('with entry reports', async () => {
+                const report = new cacheUtils.CachingReport()
+                report.entryReport('foo')
+                report.entryReport('bar')
+                report.entryReport('baz')
+
+                const stringRep = report.stringify()
+                const reportClone: cacheUtils.CachingReport = cacheUtils.CachingReport.rehydrate(stringRep)
+
+                expect(reportClone.cacheEntryReports.length).toBe(3)
+                expect(reportClone.cacheEntryReports[0].entryName).toBe('foo')
+                expect(reportClone.cacheEntryReports[1].entryName).toBe('bar')
+                expect(reportClone.cacheEntryReports[2].entryName).toBe('baz')
+
+                expect(reportClone.entryReport('foo')).toBe(reportClone.cacheEntryReports[0])
+            })
+            it('with rehydrated entry report', async () => {
+                const report = new cacheUtils.CachingReport()
+                const entryReport = report.entryReport('foo')
+                entryReport.markRequested('1', ['2', '3'])
+                entryReport.markSaved('4')
+
+                const stringRep = report.stringify()
+                const reportClone: cacheUtils.CachingReport = cacheUtils.CachingReport.rehydrate(stringRep)
+                const entryClone = reportClone.entryReport('foo')
+
+                expect(entryClone.requestedKey).toBe('1')
+                expect(entryClone.requestedRestoreKeys).toEqual(['2', '3'])
+                expect(entryClone.savedKey).toBe('4')
+            })
+            it('with live entry report', async () => {
+                const report = new cacheUtils.CachingReport()
+                const entryReport = report.entryReport('foo')
+                entryReport.markRequested('1', ['2', '3'])
+
+                const stringRep = report.stringify()
+                const reportClone: cacheUtils.CachingReport = cacheUtils.CachingReport.rehydrate(stringRep)
+                const entryClone = reportClone.entryReport('foo')
+
+                // Check type and call method on rehydrated entry report
+                expect(entryClone).toBeInstanceOf(cacheUtils.CacheEntryReport)
+                entryClone.markSaved('4')
+
+                expect(entryClone.requestedKey).toBe('1')
+                expect(entryClone.requestedRestoreKeys).toEqual(['2', '3'])
+                expect(entryClone.savedKey).toBe('4')
+            })
+        })
+    })
 })

src/cache-gradle-user-home.ts

@@ -43,7 +43,7 @@ export class GradleUserHomeCache extends AbstractCache {
         // Iterate over all bundle meta files and try to restore
         for (const bundleMetaFile of bundleMetaFiles) {
             const bundle = path.basename(bundleMetaFile, '.cache')
-            const bundleEntryReport = report.addEntryReport(bundle)
+            const bundleEntryReport = report.entryReport(bundle)
             const bundlePattern = bundlePatterns.get(bundle)
 
             // Handle case where the 'artifactBundlePatterns' have been changed
@@ -94,10 +94,10 @@ export class GradleUserHomeCache extends AbstractCache {
         return bundleFiles
     }
 
-    async beforeSave(): Promise<void> {
+    async beforeSave(report: CachingReport): Promise<void> {
         await this.reportGradleUserHomeSize('before saving common artifacts')
         this.removeExcludedPaths()
-        await this.saveArtifactBundles()
+        await this.saveArtifactBundles(report)
         await this.reportGradleUserHomeSize(
             "after saving common artifacts (only 'caches' and 'notifications' will be stored)"
         )
@@ -113,10 +113,12 @@ export class GradleUserHomeCache extends AbstractCache {
         }
     }
 
-    private async saveArtifactBundles(): Promise<void> {
+    private async saveArtifactBundles(report: CachingReport): Promise<void> {
         const processes: Promise<void>[] = []
         for (const [bundle, pattern] of this.getArtifactBundles()) {
-            const p = this.saveArtifactBundle(bundle, pattern)
+            const bundleEntryReport = report.entryReport(bundle)
+
+            const p = this.saveArtifactBundle(bundle, pattern, bundleEntryReport)
             // Run sequentially when debugging enabled
             if (this.cacheDebuggingEnabled) {
                 await p
@@ -127,7 +129,7 @@ export class GradleUserHomeCache extends AbstractCache {
         await Promise.all(processes)
     }
 
-    private async saveArtifactBundle(bundle: string, artifactPath: string): Promise<void> {
+    private async saveArtifactBundle(bundle: string, artifactPath: string, report: CacheEntryReport): Promise<void> {
         const bundleMetaFile = this.getBundleMetaFile(bundle)
 
         const globber = await glob.create(artifactPath, {
@@ -156,6 +158,7 @@ export class GradleUserHomeCache extends AbstractCache {
             core.info(`Caching ${bundle} with cache key: ${cacheKey}`)
             await this.saveCache([artifactPath], cacheKey)
             this.writeBundleMetaFile(bundleMetaFile, cacheKey)
+            report.markSaved(cacheKey)
         }
 
         for (const file of bundleFiles) {

src/cache-utils.ts

@@ -112,10 +112,30 @@ export class CachingReport {
         return this.cacheEntryReports.every(x => !x.wasRequestedButNotRestored())
     }
 
-    addEntryReport(name: string): CacheEntryReport {
-        const report = new CacheEntryReport(name)
-        this.cacheEntryReports.push(report)
-        return report
+    entryReport(name: string): CacheEntryReport {
+        for (const report of this.cacheEntryReports) {
+            if (report.entryName === name) {
+                return report
+            }
+        }
+
+        const newReport = new CacheEntryReport(name)
+        this.cacheEntryReports.push(newReport)
+        return newReport
+    }
+
+    stringify(): string {
+        return JSON.stringify(this)
+    }
+
+    static rehydrate(stringRep: string): CachingReport {
+        const rehydrated: CachingReport = Object.assign(new CachingReport(), JSON.parse(stringRep))
+        const entryReports = rehydrated.cacheEntryReports
+        for (let index = 0; index < entryReports.length; index++) {
+            const rawEntryReport = entryReports[index]
+            entryReports[index] = Object.assign(new CacheEntryReport(rawEntryReport.entryName), rawEntryReport)
+        }
+        return rehydrated
     }
 }
 
@@ -137,13 +157,20 @@ export class CacheEntryReport {
         return this.requestedKey !== undefined && this.restoredKey === undefined
     }
 
-    markRequested(key: string, restoreKeys: string[] = []): void {
+    markRequested(key: string, restoreKeys: string[] = []): CacheEntryReport {
         this.requestedKey = key
         this.requestedRestoreKeys = restoreKeys
+        return this
     }
 
-    markRestored(key: string): void {
+    markRestored(key: string): CacheEntryReport {
         this.restoredKey = key
+        return this
+    }
+
+    markSaved(key: string): CacheEntryReport {
+        this.savedKey = key
+        return this
     }
 }
 
@@ -170,7 +197,7 @@ export abstract class AbstractCache {
         }
 
         const cacheKey = this.prepareCacheKey()
-        const entryReport = report.addEntryReport(this.cacheName)
+        const entryReport = report.entryReport(this.cacheName)
         entryReport.markRequested(cacheKey.key, cacheKey.restoreKeys)
 
         this.debug(
@@ -224,7 +251,7 @@ export abstract class AbstractCache {
 
     protected async afterRestore(_report: CachingReport): Promise<void> {}
 
-    async save(): Promise<void> {
+    async save(report: CachingReport): Promise<void> {
         if (!this.cacheOutputExists()) {
             this.debug(`No ${this.cacheDescription} to cache.`)
             return
@@ -244,7 +271,7 @@ export abstract class AbstractCache {
         }
 
         try {
-            await this.beforeSave()
+            await this.beforeSave(report)
         } catch (error) {
             core.warning(`Save ${this.cacheDescription} failed in 'beforeSave': ${error}`)
             return
@@ -254,10 +281,12 @@ export abstract class AbstractCache {
         const cachePath = this.getCachePath()
         await this.saveCache(cachePath, cacheKey)
 
+        report.entryReport(this.cacheName).markSaved(cacheKey)
+
         return
     }
 
-    protected async beforeSave(): Promise<void> {}
+    protected async beforeSave(_report: CachingReport): Promise<void> {}
 
     protected async saveCache(cachePath: string[], cacheKey: string): Promise<void> {
         try {

src/caches.ts

@@ -4,6 +4,7 @@ import * as core from '@actions/core'
 import {CachingReport, isCacheDisabled, isCacheReadOnly} from './cache-utils'
 
 const BUILD_ROOT_DIR = 'BUILD_ROOT_DIR'
+const CACHING_REPORT = 'CACHING_REPORT'
 
 export async function restore(buildRootDirectory: string): Promise<void> {
     if (isCacheDisabled()) {
@@ -15,7 +16,6 @@ export async function restore(buildRootDirectory: string): Promise<void> {
         core.saveState(BUILD_ROOT_DIR, buildRootDirectory)
 
         const cachingReport = new CachingReport()
-
         await new GradleUserHomeCache(buildRootDirectory).restore(cachingReport)
 
         const projectDotGradleCache = new ProjectDotGradleCache(buildRootDirectory)
@@ -24,8 +24,11 @@ export async function restore(buildRootDirectory: string): Promise<void> {
             await projectDotGradleCache.restore(cachingReport)
         } else {
             // Otherwise, prepare the cache key for later save()
+            core.info('Gradle Home cache not fully restored: not restoring configuration-cache state')
             projectDotGradleCache.prepareCacheKey()
         }
+
+        core.saveState(CACHING_REPORT, cachingReport.stringify())
     })
 }
 
@@ -35,11 +38,19 @@ export async function save(): Promise<void> {
         return
     }
 
+    const cachingReport: CachingReport = CachingReport.rehydrate(core.getState(CACHING_REPORT))
+
     await core.group('Caching Gradle state', async () => {
         const buildRootDirectory = core.getState(BUILD_ROOT_DIR)
         return Promise.all([
-            new GradleUserHomeCache(buildRootDirectory).save(),
-            new ProjectDotGradleCache(buildRootDirectory).save()
+            new GradleUserHomeCache(buildRootDirectory).save(cachingReport),
+            new ProjectDotGradleCache(buildRootDirectory).save(cachingReport)
         ])
     })
+
+    logCachingReport(cachingReport)
+}
+
+function logCachingReport(report: CachingReport): void {
+    core.info(JSON.stringify(report, null, 2))
 }