feat: install latest mongodb binaries on package install

It helps to skip timeout setup `jasmine.DEFAULT_TIMEOUT_INTERVAL =
60000;`
when first test run hits MongoDB binary downloading to the cache.

Related #62

Author: nodkz

package.json

@@ -6,7 +6,8 @@
   "repository": "https://github.com/nodkz/mongodb-memory-server",
   "author": "Nodkz ([email protected])",
   "files": [
-    "lib"
+    "lib",
+    "postinstall.js"
   ],
   "keywords": [
     "mongodb",
@@ -71,7 +72,8 @@
     "lint": "eslint --ext .js ./src",
     "flow": "./node_modules/.bin/flow",
     "test": "npm run coverage && npm run lint && npm run flow",
-    "semantic-release": "semantic-release"
+    "semantic-release": "semantic-release",
+    "postinstall": "node ./postinstall.js"
   },
   "jest": {
     "roots": [

postinstall.js

@@ -0,0 +1,18 @@
+/*
+This script is used as postinstall hook.
+
+When you install mongodb-memory-server package
+npm or yarn downloads the latest version of mongodb binaries.
+
+It helps to skip timeout setup `jasmine.DEFAULT_TIMEOUT_INTERVAL = 60000;`
+when first test run hits MongoDB binary downloading to the cache.
+*/
+
+const MongoBinary = require('./lib/util/MongoBinary').default;
+
+console.log('mongodb-memory-server: checking MongoDB binaries cache...');
+MongoBinary.getPath({
+  version: 'latest',
+}).then(binPath => {
+  console.log(`mongodb-memory-server: binary path is ${binPath}`);
+});