judge: add cache cleaner

packages/hydrojudge/src/cache.ts

@@ -0,0 +1,44 @@
+import path from 'path';
+import fs from 'fs-extra';
+import { argv } from 'yargs';
+import { Logger } from './log';
+import { getConfig } from './config';
+
+const logger = new Logger('cache');
+
+export = function main() {
+    const CACHE_DIR = getConfig('cache_dir');
+    if (argv._[1] === 'clean') {
+        fs.emptyDirSync(CACHE_DIR);
+        logger.info('Cleaned cache.');
+    } else if (argv._[1] === 'prune') {
+        const duration = +argv.duration || 30;
+        const now = new Date().getTime();
+        const hosts = fs.readdirSync(CACHE_DIR);
+        let cnt = 0;
+        for (const host of hosts) {
+            const hostdir = path.resolve(CACHE_DIR, host);
+            if (!fs.statSync(hostdir).isDirectory()) continue;
+            const domains = fs.readdirSync(hostdir);
+            for (const domain of domains) {
+                const domaindir = path.resolve(hostdir, domain);
+                if (!fs.statSync(domaindir).isDirectory()) continue;
+                const problems = fs.readdirSync(domaindir);
+                for (const problem of problems) {
+                    const problemdir = path.resolve(domaindir, problem);
+                    if (!fs.statSync(problem).isDirectory()) continue;
+                    let lastUsage = 0;
+                    if (fs.existsSync(path.resolve(problemdir, 'lastUsage'))) {
+                        const content = fs.readFileSync(path.resolve(problemdir, 'lastUsage')).toString();
+                        lastUsage = +content || 0;
+                    }
+                    if (lastUsage + duration * 24 * 3600 * 1000 > now) continue;
+                    fs.removeSync(problemdir);
+                    cnt++;
+                    logger.info('Removed cache %s', problemdir);
+                }
+            }
+        }
+        logger.info('Done! %d items deleted.', cnt);
+    }
+};