Use dotenv to load env variables

Author: mk026

.env.example

@@ -0,0 +1,4 @@
+SERVER_PORT=8080
+MONGODB_HOST=mongodb://localhost:27017/dbname
+TOKEN_SECRET=secret
+TOKEN_EXPIRESIN=24h

.gitignore

@@ -3,3 +3,6 @@
 
 # compiled output
 /dist
+
+# config
+.env

package-lock.json

@@ -9,6 +9,7 @@
   "dependencies": {
     "bcryptjs": "^2.4.3",
     "cors": "^2.8.5",
+    "dotenv": "^16.0.1",
     "express": "^4.17.3",
     "jsonwebtoken": "^8.5.1",
     "mongoose": "^6.2.9"

package.json

@@ -1,7 +1,11 @@
-const SERVER_PORT = 8080;
-const MONGODB_HOST = 'mongodb://localhost:27017/notesappdb';
-const TOKEN_SECRET = 'secret';
-const TOKEN_EXPIRESIN = '24h';
+import dotenv from 'dotenv';
+
+dotenv.config();
+
+const SERVER_PORT = +process.env.SERVER_PORT!;
+const MONGODB_HOST = process.env.MONGODB_HOST!;
+const TOKEN_SECRET = process.env.TOKEN_SECRET!;
+const TOKEN_EXPIRESIN = process.env.TOKEN_EXPIRESIN!;
 
 const config = {
   server: {