Implement Lipa na M-Pesa using NodeJs

const express = require("express"); //For the REST API
const router = express.Router(); //For creating modular routes
const axios = require("axios"); //For making http requests to the daraja API
const port = 5000; //Arbitrary port where the server will listen on
const app = express(); //initialize the express app
app.use(express.json()); //middleware
 
// Daraja API credentials acquired from your app on the developer portal
const consumerKey = "[YOUR_CONSUMER_KEY]";
const consumerSecret = "[YOUR CONSUMER SECRET]";
 
/**
 * generateTimestamp - fundtion to generate a timestamp required for payment request as specified in the documentataion.
 * Return - a string of a timestamp formatted for the payment request
*/
const generateTimestamp = () => {
  const now = new Date();
  const year = now.getFullYear();
  const month = String(now.getMonth() + 1).padStart(2, "0");
  const day = String(now.getDate()).padStart(2, "0");
  const hours = String(now.getHours()).padStart(2, "0");
  const minutes = String(now.getMinutes()).padStart(2, "0");
  const seconds = String(now.getSeconds()).padStart(2, "0");
  return `${year}${month}${day}${hours}${minutes}${seconds}`;
};
 
/**
 * generateAccessToken - fundtion to generate an access token by authenticating you using consumer key and consumer secret.
 * Return - a string of an access token
*/
const generateAccessToken = async (consumerKey, consumerSecret) => {
  const username = consumerKey;
  const password = consumerSecret;
  const authString = `${username}:${password}`;
  const base64AuthString = btoa(authString);
  try {
    const response = await axios.get(
      "https://sandbox.safaricom.co.ke/oauth/v1/generate?grant_type=client_credentials",
      {
        headers: {
          Authorization: "Basic " + base64AuthString,
        },
      }
    );
    return response.data.access_token;
  } catch (error) {
    throw error;
  }
};
 
/**
 * generatePassword - fundtion to generate a password required for payment request as specified in the documentataion.
 * Return - a string of a timestamp formatted for the payment request
*/
const generatePassword = () => {
  const shortcode = "174379";
  const passkey =
    "bfb279f9aa9bdbcf158e97dd71a467cd2e0c893059b10f78e6b72ada1ed2c919";
  const password = Buffer.from(`${shortcode}${passkey}${timestamp}`).toString(
    "base64"
  );
  return password;
};
 
/**
 * initiatePayment - fundtion to initiate a payment request
 * Return - a json object containing transaction information
*/
const initiatePayment = async (accessToken, paymentRequest) => {
  try {
    const response = await axios.post(
      "https://sandbox.safaricom.co.ke/mpesa/stkpush/v1/processrequest",
      paymentRequest,
      {
        headers: {
          Authorization: `Bearer ${accessToken}`,
        },
      }
    );
    return response.data;
  } catch (error) {
    throw error;
  }
};
 
// Endpoint to initiate a Lipa Na M-Pesa Online Payment
router.post("/lipa", async (req, res) => {
  try {
    // Generate an access token for authentication
    const accessToken = await generateAccessToken(consumerKey, consumerSecret);
 
    // Create the payment request
    const paymentRequest = {
      BusinessShortCode: "174379",
      Password: generatePassword(),
      Timestamp: generateTimestamp();,
      TransactionType: "CustomerPayBillOnline",
      Amount: req.body.amount,
      PartyA: req.body.phone, // Customer's phone number
      PartyB: 174379,
      PhoneNumber: req.body.phone, // Customer's phone number
      CallBackURL: "PUT_A_HTTPS_CALLBACK_ENDPOINT_HERE", //The request requires a https callback url
      AccountReference: "RideWallet",
      TransactionDesc: "Fare Payment",
    };
    // Make the payment request
    const paymentResponse = await initiatePayment(accessToken, paymentRequest);
    // Handle the payment response as needed
    res.status(200).json({
      message: "Payment initiated successfully",
      data: paymentResponse,
    });
  } catch (error) {
    console.error("Error initiating payment:", error.response.data);
    res.status(500).json({ message: "Payment initiation failed" });
  }
});
 
 
app.use("/", router);
app.listen(port, () => {
  console.log(`Server running on port ${port}`);
});

{
  "phone": "254712345678",
  "AMOUNT": "1"
}

{
  "message": "Payment initiated successfully",
  "data": {
    "MerchantRequestID": "53e3-4aa8-9fe0-8fb5e4092cdd2293840",
    "CheckoutRequestID": "ws_CO_08052024032308969712737135",
    "ResponseCode": "0",
    "ResponseDescription": "Success. Request accepted for processing",
    "CustomerMessage": "Success. Request accepted for processing"
  }
}