fix(cli-repl): delete log files older than 30 days MONGOSH-830 (#950)

Author: addaleax

packages/cli-repl/src/cli-repl.spec.ts

@@ -1,4 +1,5 @@
 import { MongoshInternalError } from '@mongosh/errors';
+import bson from 'bson';
 import { once } from 'events';
 import { promises as fs } from 'fs';
 import http from 'http';
@@ -276,6 +277,22 @@ describe('CliRepl', () => {
         await onerror;
       });
 
+      it('removes old log files', async() => {
+        const oldlogfile = path.join(tmpdir.path, '60a0064774d771e863d9a1e1_log');
+        const newerlogfile = path.join(tmpdir.path, `${new bson.ObjectId()}_log`);
+        await fs.writeFile(oldlogfile, 'ignoreme');
+        await fs.writeFile(newerlogfile, 'ignoreme');
+        cliRepl = new CliRepl(cliReplOptions);
+        await cliRepl.start('', {});
+        await fs.stat(newerlogfile);
+        try {
+          await fs.stat(oldlogfile);
+          expect.fail('missed exception');
+        } catch (err) {
+          expect(err.code).to.equal('ENOENT');
+        }
+      });
+
       it('verifies the Node.js version', async() => {
         const origVersionCheckEnvVar = process.env.MONGOSH_SKIP_NODE_VERSION_CHECK;
         delete process.env.MONGOSH_SKIP_NODE_VERSION_CHECK;

packages/cli-repl/src/cli-repl.ts

@@ -279,6 +279,7 @@ class CliRepl {
    */
   async openLogStream(): Promise<Writable> {
     const path = this.shellHomeDirectory.localPath(`${this.logId}_log`);
+    await this.cleanupOldLogfiles();
     try {
       const stream = createWriteStream(path, { mode: 0o600 });
       await once(stream, 'ready');
@@ -294,6 +295,29 @@ class CliRepl {
     }
   }
 
+  async cleanupOldLogfiles(): Promise<void> {
+    const dir = this.shellHomeDirectory.localPath('');
+    let dirHandle;
+    try {
+      dirHandle = await fs.opendir(dir);
+    } catch {
+      return;
+    }
+    for await (const dirent of dirHandle) {
+      if (!dirent.isFile()) continue;
+      const { id } = dirent.name.match(/^(?<id>[a-f0-9]{24})_log$/i)?.groups ?? {};
+      if (!id) continue;
+      // Delete files older than 30 days
+      if (new bson.ObjectId(id).generationTime < (Date.now() / 1000) - 30 * 86400) {
+        try {
+          await fs.unlink(path.join(dir, dirent.name));
+        } catch (err) {
+          this.bus.emit('mongosh:error', err);
+        }
+      }
+    }
+  }
+
   warnAboutInaccessibleFile(err: Error, path?: string): void {
     this.bus.emit('mongosh:error', err);
     if (this.warnedAboutInaccessibleFiles) {