Use Gradle 8.8 features for cleanup

Gradle 8.8 introduces new features that allow us to avoid using
timestamp manipulation to force the cleanup of the Gradle User Home directory.

This solution is simpler and more robust, but relies on Gradle 8.8+ always being
used for the cache cleanup operation.

Fixes #24

sources/src/caching/cache-cleaner.ts

@@ -1,5 +1,4 @@
 import * as core from '@actions/core'
-import * as glob from '@actions/glob'
 import fs from 'fs'
 import path from 'path'
 import {provisionAndMaybeExecute} from '../execution/gradle'
@@ -13,25 +12,20 @@ export class CacheCleaner {
         this.tmpDir = tmpDir
     }
 
-    async prepare(): Promise<void> {
-        // Reset the file-access journal so that files appear not to have been used recently
-        fs.rmSync(path.resolve(this.gradleUserHome, 'caches/journal-1'), {recursive: true, force: true})
-        fs.mkdirSync(path.resolve(this.gradleUserHome, 'caches/journal-1'), {recursive: true})
-        fs.writeFileSync(
-            path.resolve(this.gradleUserHome, 'caches/journal-1/file-access.properties'),
-            'inceptionTimestamp=0'
-        )
-
-        // Set the modification time of all files to the past: this timestamp is used when there is no matching entry in the journal
-        await this.ageAllFiles()
-
-        // Touch all 'gc' files so that cache cleanup won't run immediately.
-        await this.touchAllFiles('gc.properties')
+    async prepare(): Promise<string> {
+        // Save the current timestamp
+        const timestamp = Date.now().toString()
+        core.saveState('clean-timestamp', timestamp)
+        return timestamp
     }
 
     async forceCleanup(): Promise<void> {
-        // Age all 'gc' files so that cache cleanup will run immediately.
-        await this.ageAllFiles('gc.properties')
+        const cleanTimestamp = core.getState('clean-timestamp')
+        await this.forceCleanupFilesOlderThan(cleanTimestamp)
+    }
+
+    async forceCleanupFilesOlderThan(cleanTimestamp: string): Promise<void> {
+        core.info(`Cleaning up caches before ${cleanTimestamp}`)
 
         // Run a dummy Gradle build to trigger cache cleanup
         const cleanupProjectDir = path.resolve(this.tmpDir, 'dummy-cleanup-project')
@@ -40,11 +34,31 @@ export class CacheCleaner {
             path.resolve(cleanupProjectDir, 'settings.gradle'),
             'rootProject.name = "dummy-cleanup-project"'
         )
+        fs.writeFileSync(
+            path.resolve(cleanupProjectDir, 'init.gradle'),
+            `
+            beforeSettings { settings ->
+                def cleanupTime = ${cleanTimestamp}
+            
+                settings.caches {
+                    cleanup = Cleanup.ALWAYS
+            
+                    releasedWrappers.removeUnusedEntriesOlderThan.set(cleanupTime)
+                    snapshotWrappers.removeUnusedEntriesOlderThan.set(cleanupTime)
+                    downloadedResources.removeUnusedEntriesOlderThan.set(cleanupTime)
+                    createdResources.removeUnusedEntriesOlderThan.set(cleanupTime)
+                    buildCache.removeUnusedEntriesOlderThan.set(cleanupTime)
+                }
+            }
+            `
+        )
         fs.writeFileSync(path.resolve(cleanupProjectDir, 'build.gradle'), 'task("noop") {}')
 
         await provisionAndMaybeExecute('current', cleanupProjectDir, [
             '-g',
             this.gradleUserHome,
+            '-I',
+            'init.gradle',
             '--quiet',
             '--no-daemon',
             '--no-scan',
@@ -53,23 +67,4 @@ export class CacheCleaner {
             'noop'
         ])
     }
-
-    private async ageAllFiles(fileName = '*'): Promise<void> {
-        core.debug(`Aging all files in Gradle User Home with name ${fileName}`)
-        await this.setUtimes(`${this.gradleUserHome}/**/${fileName}`, new Date(0))
-    }
-
-    private async touchAllFiles(fileName = '*'): Promise<void> {
-        core.debug(`Touching all files in Gradle User Home with name ${fileName}`)
-        await this.setUtimes(`${this.gradleUserHome}/**/${fileName}`, new Date())
-    }
-
-    private async setUtimes(pattern: string, timestamp: Date): Promise<void> {
-        const globber = await glob.create(pattern, {
-            implicitDescendants: false
-        })
-        for await (const file of globber.globGenerator()) {
-            fs.utimesSync(file, timestamp, timestamp)
-        }
-    }
 }

sources/test/jest/cache-cleanup.test.ts

@@ -1,5 +1,6 @@
 import * as exec from '@actions/exec'
 import * as core from '@actions/core'
+import * as glob from '@actions/glob'
 import fs from 'fs'
 import path from 'path'
 import {CacheCleaner} from '../../src/caching/cache-cleaner'
@@ -14,7 +15,7 @@ test('will cleanup unused dependency jars and build-cache entries', async () =>
 
     await runGradleBuild(projectRoot, 'build', '3.1')
     
-    await cacheCleaner.prepare()
+    const timestamp = await cacheCleaner.prepare()
 
     await runGradleBuild(projectRoot, 'build', '3.1.1')
 
@@ -26,7 +27,7 @@ test('will cleanup unused dependency jars and build-cache entries', async () =>
     expect(fs.existsSync(commonsMath311)).toBe(true)
     expect(fs.readdirSync(buildCacheDir).length).toBe(4) // gc.properties, build-cache-1.lock, and 2 task entries
 
-    await cacheCleaner.forceCleanup()
+    await cacheCleaner.forceCleanupFilesOlderThan(timestamp)
 
     expect(fs.existsSync(commonsMath31)).toBe(false)
     expect(fs.existsSync(commonsMath311)).toBe(true)
@@ -42,25 +43,39 @@ test('will cleanup unused gradle versions', async () => {
     // Initialize HOME with 2 different Gradle versions
     await runGradleWrapperBuild(projectRoot, 'build')
     await runGradleBuild(projectRoot, 'build')
-    
-    await cacheCleaner.prepare()
+
+    const timestamp = await cacheCleaner.prepare()
 
     // Run with only one of these versions
     await runGradleBuild(projectRoot, 'build')
 
     const gradle802 = path.resolve(gradleUserHome, "caches/8.0.2")
+    const transforms3 = path.resolve(gradleUserHome, "caches/transforms-3")
+    const metadata100 = path.resolve(gradleUserHome, "caches/modules-2/metadata-2.100")
     const wrapper802 = path.resolve(gradleUserHome, "wrapper/dists/gradle-8.0.2-bin")
     const gradleCurrent = path.resolve(gradleUserHome, "caches/8.8")
+    const metadataCurrent = path.resolve(gradleUserHome, "caches/modules-2/metadata-2.106")
 
     expect(fs.existsSync(gradle802)).toBe(true)
+    expect(fs.existsSync(transforms3)).toBe(true)
+    expect(fs.existsSync(metadata100)).toBe(true)
     expect(fs.existsSync(wrapper802)).toBe(true)
-    expect(fs.existsSync(gradleCurrent)).toBe(true)
 
-    await cacheCleaner.forceCleanup()
+    expect(fs.existsSync(gradleCurrent)).toBe(true)
+    expect(fs.existsSync(metadataCurrent)).toBe(true)
+
+    // The wrapper won't be removed if it was recently downloaded. Age it.
+    setUtimes(wrapper802, new Date(Date.now() - 48 * 60 * 60 * 1000))
+
+    await cacheCleaner.forceCleanupFilesOlderThan(timestamp)
 
     expect(fs.existsSync(gradle802)).toBe(false)
+    expect(fs.existsSync(transforms3)).toBe(false)
+    expect(fs.existsSync(metadata100)).toBe(false)
     expect(fs.existsSync(wrapper802)).toBe(false)
+
     expect(fs.existsSync(gradleCurrent)).toBe(true)
+    expect(fs.existsSync(metadataCurrent)).toBe(true)
 })
 
 async function runGradleBuild(projectRoot: string, args: string, version: string = '3.1'): Promise<void> {
@@ -86,3 +101,9 @@ function prepareTestProject(): string {
     return projectRoot
 }
 
+async function setUtimes(pattern: string, timestamp: Date): Promise<void> {
+    const globber = await glob.create(pattern)
+    for await (const file of globber.globGenerator()) {
+        fs.utimesSync(file, timestamp, timestamp)
+    }
+}