Moved cache-related code into subpackage

sources/src/caching/cache-cleaner.ts

@@ -0,0 +1,69 @@
+import * as core from '@actions/core'
+import * as exec from '@actions/exec'
+import * as glob from '@actions/glob'
+import fs from 'fs'
+import path from 'path'
+
+export class CacheCleaner {
+    private readonly gradleUserHome: string
+    private readonly tmpDir: string
+
+    constructor(gradleUserHome: string, tmpDir: string) {
+        this.gradleUserHome = gradleUserHome
+        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 forceCleanup(): Promise<void> {
+        // Age all 'gc' files so that cache cleanup will run immediately.
+        await this.ageAllFiles('gc.properties')
+
+        // Run a dummy Gradle build to trigger cache cleanup
+        const cleanupProjectDir = path.resolve(this.tmpDir, 'dummy-cleanup-project')
+        fs.mkdirSync(cleanupProjectDir, {recursive: true})
+        fs.writeFileSync(
+            path.resolve(cleanupProjectDir, 'settings.gradle'),
+            'rootProject.name = "dummy-cleanup-project"'
+        )
+        fs.writeFileSync(path.resolve(cleanupProjectDir, 'build.gradle'), 'task("noop") {}')
+
+        const gradleCommand = `gradle -g ${this.gradleUserHome} --no-daemon --build-cache --no-scan --quiet -DGITHUB_DEPENDENCY_GRAPH_ENABLED=false noop`
+        await exec.exec(gradleCommand, [], {
+            cwd: cleanupProjectDir
+        })
+    }
+
+    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)
+        }
+    }
+}