fix(build): add mongo_killer.js to the package

Resolves #151

Author: AJRdev

.eslintignore

@@ -1,3 +1,2 @@
 flow-typed/*
 lib/*
-postinstall.js

.old.tslint.json

@@ -7,7 +7,7 @@
   "repository": "https://github.com/nodkz/mongodb-memory-server",
   "files": [
     "lib",
-    "postinstall.js"
+    "scripts"
   ],
   "keywords": [
     "mongodb",
@@ -80,7 +80,7 @@
     "test": "npm run lint && npm run tscheck && npm run coverage",
     "tscheck": "tsc --noEmit",
     "semantic-release": "semantic-release",
-    "postinstall": "node ./postinstall.js"
+    "postinstall": "node ./scripts/postinstall.js"
   },
   "config": {
     "commitizen": {

package.json

@@ -1,13 +1,14 @@
-/* eslint-disable */
 /*
-    make sure every few seconds that parent is still alive
-    and if it is dead, we will kill child too.
-    this is to ensure that exits done via kill
-    wont leave mongod around
+  Make sure every few seconds that `parent` and `child` are alive:
+  - if `parent` is dead:
+    - kill child
+    - kill itself
+  - if `child` is dead:
+    - kill itself
 */
 
-var parentPid = parseInt(process.argv[2], 10);
-var childPid = parseInt(process.argv[3], 10);
+const parentPid = parseInt(process.argv[2], 10);
+const childPid = parseInt(process.argv[3], 10);
 
 if (parentPid && childPid) {
   setInterval(() => {

src/util/mongo_killer.js renamed to scripts/mongo_killer.js

@@ -25,15 +25,15 @@ if (skipDownload) {
   process.exit(0);
 }
 
-if (isModuleExists('./lib/util/MongoBinary')) {
-  const MongoBinary = require('./lib/util/MongoBinary').default;
+if (isModuleExists('../lib/util/MongoBinary')) {
+  const MongoBinary = require('../lib/util/MongoBinary').default;
 
   console.log('mongodb-memory-server: checking MongoDB binaries cache...');
   MongoBinary.getPath({})
-    .then(binPath => {
+    .then((binPath) => {
       console.log(`mongodb-memory-server: binary path is ${binPath}`);
     })
-    .catch(err => {
+    .catch((err) => {
       console.log(`failed to download/install MongoDB binaries. The error:
 ${err}`);
       process.exit(0);

postinstall.js renamed to scripts/postinstall.js

@@ -169,13 +169,24 @@ export default class MongoInstance {
   }
 
   _launchKiller(parentPid: number, childPid: number): ChildProcess {
+    this.debug(`Called MongoInstance._launchKiller(parent: ${parentPid}, child: ${childPid}):`);
     // spawn process which kills itself and mongo process if current process is dead
     const killer = spawnChild(
       process.argv[0],
-      [path.resolve(__dirname, 'mongo_killer.js'), parentPid.toString(), childPid.toString()],
+      [
+        path.resolve(__dirname, '../../scripts/mongo_killer.js'),
+        parentPid.toString(),
+        childPid.toString(),
+      ],
       { stdio: 'pipe' }
     );
 
+    ['exit', 'message', 'disconnect', 'error'].forEach((e) => {
+      killer.on(e, (...args) => {
+        this.debug(`[MongoKiller]: ${e} - ${JSON.stringify(args)}`);
+      });
+    });
+
     return killer;
   }