feat(cli-repl): add configuration to set log retention days MONGOSH-1984

 (#2349)

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

@@ -323,6 +323,7 @@ describe('CliRepl', function () {
           'updateURL',
           'disableLogging',
           'logLocation',
+          'logRetentionDays',
         ] satisfies (keyof CliUserConfig)[]);
       });
 
@@ -1443,6 +1444,19 @@ describe('CliRepl', function () {
               )
             );
           });
+
+          it('can set log retention days', async function () {
+            const testRetentionDays = 123;
+            cliRepl.config.logRetentionDays = testRetentionDays;
+            await cliRepl.start(await testServer.connectionString(), {});
+
+            expect(await cliRepl.getConfig('logRetentionDays')).equals(
+              testRetentionDays
+            );
+            expect(cliRepl.logManager?._options.retentionDays).equals(
+              testRetentionDays
+            );
+          });
         });
 
         it('times out fast', async function () {

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

@@ -259,7 +259,7 @@ export class CliRepl implements MongoshIOProvider {
       directory:
         (await this.getConfig('logLocation')) ||
         this.shellHomeDirectory.localPath('.'),
-      retentionDays: 30,
+      retentionDays: await this.getConfig('logRetentionDays'),
       maxLogFileCount: +(
         process.env.MONGOSH_TEST_ONLY_MAX_LOG_FILE_COUNT || 100
       ),

packages/e2e-tests/test/e2e.spec.ts

@@ -1,7 +1,7 @@
 /* eslint-disable no-control-regex */
 import { expect } from 'chai';
 import type { Db } from 'mongodb';
-import { MongoClient } from 'mongodb';
+import { MongoClient, ObjectId } from 'mongodb';
 
 import { eventually } from '../../../testing/eventually';
 import { TestShell } from './test-shell';
@@ -1676,6 +1676,77 @@ describe('e2e', function () {
           });
         });
 
+        /** Helper to visualize and compare the existence of files in a specific order.
+         * Returns a string comprised of: 1 if a given file exists, 0 otherwise. */
+        const getFilesState = async (paths: string[]) => {
+          return (
+            await Promise.all(
+              paths.map((path) =>
+                fs.stat(path).then(
+                  () => 1,
+                  () => 0
+                )
+              )
+            )
+          ).join('');
+        };
+
+        describe('with custom log retention days', function () {
+          const customLogDir = useTmpdir();
+
+          it('should delete older files according to the setting', async function () {
+            const paths: string[] = [];
+            const today = Math.floor(Date.now() / 1000);
+            const tenDaysAgo = today - 10 * 24 * 60 * 60;
+            // Create 6 files older than 7 days
+            for (let i = 5; i >= 0; i--) {
+              const filename = path.join(
+                customLogDir.path,
+                ObjectId.createFromTime(tenDaysAgo - i).toHexString() + '_log'
+              );
+              await fs.writeFile(filename, '');
+              paths.push(filename);
+            }
+            // Create 4 files newer than 10 days
+            for (let i = 3; i >= 0; i--) {
+              const filename = path.join(
+                customLogDir.path,
+                ObjectId.createFromTime(today - i).toHexString() + '_log'
+              );
+              await fs.writeFile(filename, '');
+              paths.push(filename);
+            }
+
+            const retentionDays = 7;
+
+            const globalConfig = path.join(homedir, 'globalconfig.conf');
+            await fs.writeFile(
+              globalConfig,
+              `mongosh:\n  logLocation: ${JSON.stringify(
+                customLogDir.path
+              )}\n  logRetentionDays: ${retentionDays}`
+            );
+
+            expect(await getFilesState(paths)).equals('1111111111');
+
+            shell = this.startTestShell({
+              args: ['--nodb'],
+              env: {
+                ...env,
+                MONGOSH_GLOBAL_CONFIG_FILE_FOR_TESTING: globalConfig,
+              },
+              forceTerminal: true,
+            });
+
+            await shell.waitForPrompt();
+
+            // Add the newly created log file
+            paths.push(path.join(customLogDir.path, `${shell.logId}_log`));
+            // Expect 6 files to be deleted and 5 to remain (including the new log file)
+            expect(await getFilesState(paths)).equals('00000011111');
+          });
+        });
+
         it('creates a log file that keeps track of session events', async function () {
           expect(await shell.executeLine('print(123 + 456)')).to.include('579');
           const log = await readLogFile();

packages/types/src/index.spec.ts

@@ -25,6 +25,12 @@ describe('config validation', function () {
     expect(await validate('historyLength', 0)).to.equal(null);
     expect(await validate('historyLength', 1)).to.equal(null);
     expect(await validate('historyLength', Infinity)).to.equal(null);
+    expect(await validate('logRetentionDays', 'foo')).to.equal(
+      'logRetentionDays must be a positive integer'
+    );
+    expect(await validate('logRetentionDays', -1)).to.equal(
+      'logRetentionDays must be a positive integer'
+    );
     expect(await validate('showStackTraces', 'foo')).to.equal(
       'showStackTraces must be a boolean'
     );

packages/types/src/index.ts

@@ -509,6 +509,7 @@ export class CliUserConfig extends SnippetShellUserConfig {
   updateURL = 'https://downloads.mongodb.com/compass/mongosh.json';
   disableLogging = false;
   logLocation: string | undefined = undefined;
+  logRetentionDays = 30;
 }
 
 export class CliUserConfigValidator extends SnippetShellUserConfigValidator {
@@ -531,6 +532,7 @@ export class CliUserConfigValidator extends SnippetShellUserConfigValidator {
         return null;
       case 'inspectDepth':
       case 'historyLength':
+      case 'logRetentionDays':
         if (typeof value !== 'number' || value < 0) {
           return `${key} must be a positive integer`;
         }