Send Email at the time of transaction with nodemailer OAuth2. Fixes #46 - Task 2 (Complete)

app.js

@@ -16,7 +16,7 @@ const session = require("express-session");
 const mongoose = require("mongoose");
 const MongoStore = require("connect-mongo")(session);
 const connectDB = require("./config/db");
-const flash = require('connect-flash');
+const flash = require("connect-flash");
 
 // Load config
 dotenv.config({ path: "./config/config.env" });
@@ -78,15 +78,15 @@ app.use(passport.initialize());
 app.use(passport.session());
 
 // Connect Flash
-app.use(flash())
+app.use(flash());
 
 // Set Global variables
-app.use(function(req, res, next) {
-    res.locals.user = req.user || null;
-    res.locals.success_msg = req.flash('success_msg');
-    res.locals.error_msg = req.flash('error_msg');
-    res.locals.error = req.flash('error');
-    next();
+app.use(function (req, res, next) {
+  res.locals.user = req.user || null;
+  res.locals.success_msg = req.flash("success_msg");
+  res.locals.error_msg = req.flash("error_msg");
+  res.locals.error = req.flash("error");
+  next();
 });
 
 // Static folder

helpers/emailHelper.js

@@ -0,0 +1,30 @@
+require("dotenv").config();
+const nodemailer = require("nodemailer");
+
+const transporter = nodemailer.createTransport({
+  host: "smtp.gmail.com",
+  port: 465,
+  secure: true,
+  auth: {
+    type: "OAuth2",
+    user: process.env.GMAIL_ADDRESS,
+    clientId: process.env.GMAIL_OAUTH_CLIENT_ID,
+    clientSecret: process.env.GMAIL_OAUTH_CLIENT_SECRET,
+    refreshToken: process.env.GMAIL_OAUTH_REFRESH_TOKEN,
+    accessToken: process.env.GMAIL_OAUTH_ACCESS_TOKEN,
+    expires: Number.parseInt(process.env.GMAIL_OAUTH_TOKEN_EXPIRE, 10),
+  },
+});
+
+exports.sendEmail = (mailOptions) =>
+  new Promise((resolve, reject) => {
+    transporter.sendMail(mailOptions, (error) => {
+      if (error) {
+        console.error(error.stack || error);
+        return reject(error);
+      }
+      resolve();
+    });
+  }).catch((error) => {
+    console.log(error);
+  });