refactor: error handling connection, use dotenv

package.json

@@ -14,6 +14,7 @@
     "body-parser": "^1.19.0",
     "cookie-parser": "^1.4.4",
     "cors": "^2.8.5",
+    "dotenv": "^8.2.0",
     "express": "^4.17.1",
     "jsonwebtoken": "^8.5.1",
     "mongodb": "^3.5.1",

src/config.js

@@ -1,7 +1,15 @@
+import dotenv from "dotenv";
+
+const CONFIG = dotenv.config();
+const {
+  parsed: { DB_USER, DB_PASSWORD, ...rest }
+} = CONFIG;
+
+const URI = `mongodb+srv://${DB_USER}:${DB_PASSWORD}@cluster0-diifo.mongodb.net/db_z0?retryWrites=true&w=majority`;
+
 const config = {
-  port: 8000,
-  jwtExpirationSeconds: 300,
-  JWT_KEY: "my_secret"
+  URI,
+  ...rest
 };
 
 export default config;

src/db/connect.js

@@ -1,29 +1,36 @@
 import mongoose from "mongoose";
+import config from "../config";
 
-const uri =
-  "mongodb+srv://agileactors:[email protected]/db_z0?retryWrites=true&w=majority";
-const db = mongoose.connection;
+const { URI } = config;
 
 // setup mongoose
 mongoose.Promise = global.Promise;
 mongoose.set("useCreateIndex", true);
 
 const connect = () => {
-  try {
-    mongoose.connect(uri, {
+  const db = mongoose.connection;
+  const resultP = new Promise((resolve, reject) => {
+    mongoose.connect(URI, {
       useNewUrlParser: true,
       useUnifiedTopology: true
     });
 
-    //bind connection to error event (to get notification of connection errors)
-    db.on("error", console.error.bind(console, "MongoDB connection error:"));
+    db.on("error", error =>
+      reject({
+        success: false,
+        message: error
+      })
+    );
 
     db.once("open", () => {
-      console.log("database connection: OK");
+      resolve({
+        success: true,
+        message: "database connection: OK"
+      });
     });
-  } catch (error) {
-    console.error(error);
-  }
+  });
+
+  return resultP;
 };
 
 export default connect;

src/server.js

@@ -5,15 +5,18 @@ import config from "./config";
 import { connect } from "./db";
 import { userRouter } from "./routers";
 
-const { port } = config || 8000;
+const { PORT } = config || 8000;
 const app = express();
 
 app.use(cors());
 app.use(bodyParser.urlencoded({ extended: true }));
 app.use(bodyParser.json());
 app.use(userRouter);
 
-app.listen(port, () => {
-  console.log(`Server is running at port: ${port}`);
-  connect();
+app.listen(PORT, () => {
+  console.log(`Server is running at port: ${PORT}`);
+
+  connect()
+    .then(({ message }) => console.log(message))
+    .catch(error => console.log(error));
 });