fix(debug): improve debug messages for kill() command

Related #151

Author: nodkz

src/MongoMemoryServer.ts

@@ -63,6 +63,7 @@ export default class MongoMemoryServer {
   }
 
   async start(): Promise<boolean> {
+    this.debug('Called MongoMemoryServer.start() method:');
     if (this.runningInstance) {
       throw new Error(
         'MongoDB instance already in status startup/running/error. Use opts.debug = true for more info.'
@@ -142,6 +143,8 @@ export default class MongoMemoryServer {
   }
 
   async stop(): Promise<boolean> {
+    this.debug('Called MongoMemoryServer.stop() method');
+
     const { instance, port, tmpDir }: MongoInstanceDataT = await this.getInstanceData();
 
     this.debug(`Shutdown MongoDB server on port ${port} with pid ${instance.getPid() || ''}`);
@@ -157,8 +160,11 @@ export default class MongoMemoryServer {
   }
 
   async getInstanceData(): Promise<MongoInstanceDataT> {
+    this.debug('Called MongoMemoryServer.getInstanceData() method:');
     if (!this.runningInstance) {
+      this.debug(' - no running instance, call `start()` command');
       await this.start();
+      this.debug(' - `start()` command was succesfully resolved');
     }
     if (this.runningInstance) {
       return this.runningInstance;

src/__tests__/MongoMemoryServer-test.ts

@@ -1,33 +1,32 @@
-import MongoMemoryServer from '../MongoMemoryServer';
+import MongoMemoryServerType from '../MongoMemoryServer';
 
 jasmine.DEFAULT_TIMEOUT_INTERVAL = 600000;
 
 describe('MongoMemoryServer', () => {
-  describe('start', () => {
-    const mockStartUpInstance = jest.fn();
-
-    afterEach(() => {
-      mockStartUpInstance.mockClear();
-    });
+  let MongoMemoryServer: typeof MongoMemoryServerType;
+  beforeEach(() => {
+    jest.resetModules();
+    MongoMemoryServer = jest.requireActual('../MongoMemoryServer').default;
+  });
 
+  describe('start', () => {
     it('should resolve to true if an MongoInstanceData is resolved by _startUpInstance', async () => {
-      mockStartUpInstance.mockResolvedValue({});
-      MongoMemoryServer.prototype._startUpInstance = mockStartUpInstance;
+      MongoMemoryServer.prototype._startUpInstance = jest.fn(() => Promise.resolve({} as any));
 
       const mongoServer = new MongoMemoryServer({ autoStart: false });
 
-      expect(mockStartUpInstance).toHaveBeenCalledTimes(0);
+      expect(MongoMemoryServer.prototype._startUpInstance).toHaveBeenCalledTimes(0);
 
       await expect(mongoServer.start()).resolves.toEqual(true);
 
-      expect(mockStartUpInstance).toHaveBeenCalledTimes(1);
+      expect(MongoMemoryServer.prototype._startUpInstance).toHaveBeenCalledTimes(1);
     });
 
     it('_startUpInstance should be called a second time if an error is thrown on the first call and assign the current port to nulll', async () => {
-      mockStartUpInstance
+      MongoMemoryServer.prototype._startUpInstance = jest
+        .fn()
         .mockRejectedValueOnce(new Error('Mongod shutting down'))
         .mockResolvedValueOnce({});
-      MongoMemoryServer.prototype._startUpInstance = mockStartUpInstance;
 
       const mongoServer = new MongoMemoryServer({
         autoStart: false,
@@ -36,16 +35,17 @@ describe('MongoMemoryServer', () => {
         },
       });
 
-      expect(mockStartUpInstance).toHaveBeenCalledTimes(0);
+      expect(MongoMemoryServer.prototype._startUpInstance).toHaveBeenCalledTimes(0);
 
       await expect(mongoServer.start()).resolves.toEqual(true);
 
-      expect(mockStartUpInstance).toHaveBeenCalledTimes(2);
+      expect(MongoMemoryServer.prototype._startUpInstance).toHaveBeenCalledTimes(2);
     });
 
     it('should throw an error if _startUpInstance throws an unknown error', async () => {
-      mockStartUpInstance.mockRejectedValueOnce(new Error('unknown error'));
-      MongoMemoryServer.prototype._startUpInstance = mockStartUpInstance;
+      MongoMemoryServer.prototype._startUpInstance = jest
+        .fn()
+        .mockRejectedValueOnce(new Error('unknown error'));
 
       const mongoServer = new MongoMemoryServer({
         autoStart: false,
@@ -54,34 +54,43 @@ describe('MongoMemoryServer', () => {
         },
       });
 
-      expect(mockStartUpInstance).toHaveBeenCalledTimes(0);
+      expect(MongoMemoryServer.prototype._startUpInstance).toHaveBeenCalledTimes(0);
 
       await expect(mongoServer.start()).rejects.toThrow(
         `unknown error\n\nUse debug option for more info: ` +
           `new MongoMemoryServer({ debug: true })`
       );
 
-      expect(mockStartUpInstance).toHaveBeenCalledTimes(1);
+      expect(MongoMemoryServer.prototype._startUpInstance).toHaveBeenCalledTimes(1);
     });
   });
-  describe('getInstanceData', () => {
-    const mockStart = jest.fn();
-
-    afterEach(() => {
-      mockStart.mockClear();
-    });
 
+  describe('getInstanceData', () => {
     it('should throw an error if not instance is running after calling start', async () => {
-      mockStart.mockResolvedValue(true);
-      MongoMemoryServer.prototype.start = mockStart;
+      MongoMemoryServer.prototype.start = jest.fn(() => Promise.resolve(true));
 
       const mongoServer = new MongoMemoryServer({ autoStart: false });
 
       await expect(mongoServer.getInstanceData()).rejects.toThrow(
         'Database instance is not running. You should start database by calling start() method. BTW it should start automatically if opts.autoStart!=false. Also you may provide opts.debug=true for more info.'
       );
 
-      expect(mockStart).toHaveBeenCalledTimes(1);
+      expect(MongoMemoryServer.prototype.start).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  describe('stop', () => {
+    it.only('should stop mongod', async () => {
+      console.log(MongoMemoryServer.prototype._startUpInstance);
+      const mongod = new MongoMemoryServer({
+        autoStart: true,
+        debug: true,
+      });
+
+      await mongod.getInstanceData();
+
+      await mongod.stop();
+      expect(mongod.runningInstance).toBe(null);
     });
   });
 });

src/util/MongoInstance.ts

@@ -1,6 +1,3 @@
-/* @flow */
-/* eslint-disable class-methods-use-this */
-
 import { ChildProcess, spawn as spawnChild } from 'child_process';
 import path from 'path';
 import MongoBinary from './MongoBinary';
@@ -119,21 +116,34 @@ export default class MongoInstance {
   }
 
   async kill(): Promise<MongoInstance> {
+    this.debug('Called MongoInstance.kill():');
     if (this.childProcess && !this.childProcess.killed) {
       await new Promise((resolve) => {
         if (this.childProcess) {
-          this.childProcess.once(`exit`, resolve);
+          this.childProcess.once(`exit`, () => {
+            this.debug(' - childProcess: got exit signal. Ok!');
+            resolve();
+          });
           this.childProcess.kill();
+          this.debug(' - childProcess: send kill cmd...');
         }
       });
+    } else {
+      this.debug(' - childProcess: nothing to kill, skipping.');
     }
     if (this.killerProcess && !this.killerProcess.killed) {
       await new Promise((resolve) => {
         if (this.killerProcess) {
-          this.killerProcess.once(`exit`, resolve);
+          this.killerProcess.once(`exit`, () => {
+            this.debug(' - killerProcess: got exit signal. Ok!');
+            resolve();
+          });
           this.killerProcess.kill();
+          this.debug(' - killerProcess: send kill cmd...');
         }
       });
+    } else {
+      this.debug(' - killerProcess: nothing to kill, skipping.');
     }
     return this;
   }