Node.js Express Stripe Webhooks Live URL Example to Send Invoice Email Using NGROK & Nodemailer

Welcome folks today in this blog post we will be sending invoice email using the nodemailer library to integrate stripe checkout in browser using javascript. All the full source code of the application is shown below.

Get Started

In order to get started you need to make a new node.js project using the below command as shown below

npm init -y

npm i express

npm i stripe

npm i nodemailer

npm i dotenv

After that you will see the below directory structure of the node.js app as shown below

Now we need to create the index.js file and copy paste the following code

index.js

const stripe = require("stripe")("##secretkey##");
 
const express = require("express");
 
const dotenv = require('dotenv')
 
dotenv.config()
 
const nodemailer = require("nodemailer");
 
const app = express();
 
// deploy this app publicly ngrok
 
app.get("/", (req, res) => {
  res.send("hello world dfgdfgfdgdfgdf");
});
let endpointSecret = "signingsecret";
let session = "";
let product = "https://drive.google.com/file/d/1O6thKAum6JKB5n4cJLLauZ4dFGRHRcmk/view?usp=sharing"
 
// webhook
 
app.post(
  "/webhooks",
  express.raw({ type: "application/json" }),
  async(request, response) => {
    const sig = request.headers["stripe-signature"];
    // stripe
 
    let event;
 
    try {
      event = stripe.webhooks.constructEvent(request.body, sig, endpointSecret);
    } catch (err) {
      response.status(400).send(`Webhook Error: ${err.message}`);
      return;
    }
 
    // Handle the event
    switch (event.type) {
      case "checkout.session.async_payment_failed":
        session = event.data.object;
        console.log(session);
        // Then define and call a function to handle the event checkout.session.async_payment_failed
        break;
      case "checkout.session.completed":
        session = event.data.object;
        console.log(session);
 
        let emailto = session.customer_details.email;
 
        let transporter = nodemailer.createTransport({
          host: "smtp.gmail.com",
          port: 587,
          secure: false, // true for 465, false for other ports
          auth: {
            user: process.env.email, // generated ethereal user
            pass: process.env.password, // generated ethereal password
          },
        });
 
        // send mail with defined transport object
        let info = await transporter.sendMail({
          from: process.env.email, // sender address
          to: emailto, // list of receivers
          subject: "Thanks for the Payment for the Product", // Subject line
          text: "Thanks for the payment for the product", // plain text body
          html: `
          
            Hello ${session.customer_details.email} Thanks for the payment for the product
            Here is the link of the product from google drive ${product} . You can download
            the file by going to this link
          
            `, // html body
        });
 
        console.log("Message sent: %s", info.messageId);
        // send invoice email using nodemailer
        // Then define and call a function to handle the event checkout.session.async_payment_succeeded
        break;
      // ... handle other event types
      default:
        console.log(`Unhandled event type ${event.type}`);
    }
 
    // Return a 200 response to acknowledge receipt of the event
    response.send();
  }
);
app.listen(5000, () => {
  console.log("App is listening on port 5000");
});

const stripe = require("stripe")("##secretkey##");

const express = require("express");

const dotenv = require('dotenv')

dotenv.config()

const nodemailer = require("nodemailer");

const app = express();

// deploy this app publicly ngrok

app.get("/", (req, res) => {

res.send("hello world dfgdfgfdgdfgdf");

});

let endpointSecret = "signingsecret";

let session = "";

let product = "https://drive.google.com/file/d/1O6thKAum6JKB5n4cJLLauZ4dFGRHRcmk/view?usp=sharing"

// webhook

app.post(

"/webhooks",

express.raw({ type: "application/json" }),

async(request, response) => {

const sig = request.headers["stripe-signature"];

// stripe

let event;

try {

event = stripe.webhooks.constructEvent(request.body, sig, endpointSecret);

} catch (err) {

response.status(400).send(`Webhook Error: ${err.message}`);

return;

}

// Handle the event

switch (event.type) {

case "checkout.session.async_payment_failed":

session = event.data.object;

console.log(session);

// Then define and call a function to handle the event checkout.session.async_payment_failed

break;

case "checkout.session.completed":

session = event.data.object;

console.log(session);

let emailto = session.customer_details.email;

let transporter = nodemailer.createTransport({

host: "smtp.gmail.com",

port: 587,

secure: false, // true for 465, false for other ports

auth: {

user: process.env.email, // generated ethereal user

pass: process.env.password, // generated ethereal password

});

// send mail with defined transport object

let info = await transporter.sendMail({

from: process.env.email, // sender address

to: emailto, // list of receivers

subject: "Thanks for the Payment for the Product", // Subject line

text: "Thanks for the payment for the product", // plain text body

html: `

Hello ${session.customer_details.email} Thanks for the payment for the product

Here is the link of the product from google drive ${product} . You can download

the file by going to this link

`, // html body

});

console.log("Message sent: %s", info.messageId);

// send invoice email using nodemailer

// Then define and call a function to handle the event checkout.session.async_payment_succeeded

break;

// ... handle other event types

default:

console.log(`Unhandled event type ${event.type}`);

}

// Return a 200 response to acknowledge receipt of the event

response.send();

}

);

app.listen(5000, () => {

console.log("App is listening on port 5000");

});

As you can see we are importing the express and stripe modules at the very top and here you need to replace the secret key from the stripe dashboard and then we are starting the express app at port 5000 and here we have the post request at the /webhooks endpoint and here we need to deploy this node.js app to live url using ngrok library.

And now we need to go to webhooks and basically we are listening on various events for the checkout event as shown below

Now we need to create the .env file where we will be storing the email and password as shown below

.env

email=##youremail##
password=##yourpassword##

1 2	email=##youremail## password=##yourpassword##