fix(MongoInstance::closeHandler): emit "instanceError" on non-0 (or non-12) code

fixes #693

Author: hasezoey

packages/mongodb-memory-server-core/src/util/MongoInstance.ts

@@ -13,7 +13,12 @@ import {
 import { lt } from 'semver';
 import { EventEmitter } from 'events';
 import { MongoClient, MongoClientOptions, MongoNetworkError } from 'mongodb';
-import { KeyFileMissingError, StartBinaryFailedError, StdoutInstanceError } from './errors';
+import {
+  KeyFileMissingError,
+  StartBinaryFailedError,
+  StdoutInstanceError,
+  UnexpectedCloseError,
+} from './errors';
 
 // ignore the nodejs warning for coverage
 /* istanbul ignore next */
@@ -508,6 +513,7 @@ export class MongoInstance extends EventEmitter implements ManagerBase {
     // https://docs.mongodb.com/manual/reference/exit-codes/#12
     if ((process.platform === 'win32' && code != 12 && code != 0) || code != 0) {
       this.debug('closeHandler: Mongod instance closed with an non-0 (or non 12 on windows) code!');
+      this.emit(MongoInstanceEvents.instanceError, new UnexpectedCloseError(code, signal));
     }
 
     this.debug(`closeHandler: code: "${code}", signal: "${signal}"`);

packages/mongodb-memory-server-core/src/util/__tests__/MongoInstance.test.ts

@@ -4,7 +4,7 @@ import * as dbUtil from '../utils';
 import MongodbInstance, { MongoInstanceEvents } from '../MongoInstance';
 import resolveConfig, { ResolveConfigVariables } from '../resolveConfig';
 import getPort from 'get-port';
-import { StartBinaryFailedError, StdoutInstanceError } from '../errors';
+import { StartBinaryFailedError, StdoutInstanceError, UnexpectedCloseError } from '../errors';
 import { assertIsError } from '../../__tests__/testUtils/test_utils';
 
 jest.setTimeout(100000); // 10s
@@ -331,8 +331,43 @@ describe('MongodbInstance', () => {
         events.clear();
         mongod.closeHandler(null, 'SIG');
 
-        expect(events.size).toEqual(1);
+        expect(events.size).toEqual(2);
         expect(events.get(MongoInstanceEvents.instanceClosed)).toEqual([null, 'SIG']);
+
+        const event = events.get(MongoInstanceEvents.instanceError)?.[0];
+        expect(event).toBeInstanceOf(UnexpectedCloseError);
+        assertIsError(event); // has to be used, because there is not typeguard from "expect(variable).toBeInstanceOf"
+        expect(event.message).toMatchSnapshot();
+      }
+    });
+
+    it('"closeHandler" should emit "instanceError" with non-0 or non-12 code', () => {
+      // test code non-0
+      {
+        events.clear();
+        mongod.closeHandler(1, null);
+
+        expect(events.size).toEqual(2);
+        expect(events.get(MongoInstanceEvents.instanceClosed)).toEqual([1, null]);
+
+        const event = events.get(MongoInstanceEvents.instanceError)?.[0];
+        expect(event).toBeInstanceOf(UnexpectedCloseError);
+        assertIsError(event); // has to be used, because there is not typeguard from "expect(variable).toBeInstanceOf"
+        expect(event.message).toMatchSnapshot();
+      }
+
+      // test signal
+      {
+        events.clear();
+        mongod.closeHandler(null, 'SIG');
+
+        expect(events.size).toEqual(2);
+        expect(events.get(MongoInstanceEvents.instanceClosed)).toEqual([null, 'SIG']);
+
+        const event = events.get(MongoInstanceEvents.instanceError)?.[0];
+        expect(event).toBeInstanceOf(UnexpectedCloseError);
+        assertIsError(event); // has to be used, because there is not typeguard from "expect(variable).toBeInstanceOf"
+        expect(event.message).toMatchSnapshot();
       }
     });
 

packages/mongodb-memory-server-core/src/util/__tests__/__snapshots__/MongoInstance.test.ts.snap

@@ -6,6 +6,12 @@ exports[`MongodbInstance prepareCommandArgs should throw an error if no dbpath i
 
 exports[`MongodbInstance prepareCommandArgs should throw an error if no port is provided 1`] = `"\\"instanceOpts.port\\" is required to be set!"`;
 
+exports[`MongodbInstance test events "closeHandler" should emit "instanceClosed" 1`] = `"Instance closed unexpectedly with code \\"null\\" and signal \\"SIG\\""`;
+
+exports[`MongodbInstance test events "closeHandler" should emit "instanceError" with non-0 or non-12 code 1`] = `"Instance closed unexpectedly with code \\"1\\" and signal \\"null\\""`;
+
+exports[`MongodbInstance test events "closeHandler" should emit "instanceError" with non-0 or non-12 code 2`] = `"Instance closed unexpectedly with code \\"null\\" and signal \\"SIG\\""`;
+
 exports[`MongodbInstance test events checkErrorInLine() should emit "instanceError" when shared libraries fail to load 1`] = `"Instance failed to start because a library is missing or cannot be opened: \\"libcrypto.so.1.1\\""`;
 
 exports[`MongodbInstance test events stdoutHandler() should emit "instanceError" when "excepetion in initAndListen" is thrown DBException in initAndListen 1`] = `