Intergation with an Express js app

caution

Warning! 🚧 WIP!#

In this tutorial, we will learn the Express framework and how to intergate the pesa-js sdk. This Expressjs is built in such a way that it acts as a minimal and flexible Node.js web application framework, providing a robust set of features for building single and multipage, and hybrid web application.

info

This is a very basic example show casing the Customer to Bussiness transaction

In this tutorial, you will learn-

What is Express.js?
Installing and using Express, Routes?
Sample Web server using express.js
Intergrating Pesa sdk

What is Express.js?#

Express.js is a Node js web application server framework, which is specifically designed for building single-page, multi-page, and hybrid web applications.

It has become the standard server framework for Node.js. Express is the backend part of something known as the MERN stack.

Installing and using Express#

We will be using express-generator to quickly create an application skeleton. You can run the application generator with the npx command (available in Node.js 8.2.0 +).

npx express-generator --no-view myapp

An Express app named myapp will be created in a folder named myapp/ in the current working directory, no view engine will be set;

src/app.js

const express = require('express');
const app = express();
const port = 3000;

app.get('/', (req, res) => {
    res.send('Hello World!');
});

app.listen(port, () => {
    console.log(`Example app listening at http://localhost:${port}`);
});

Run the app with the following command:

node src/app.js

Then, load http://localhost:3000/ in a browser to see the output. or run curl

curl http://localhost:3000/

Intergrating Pesa sdk#

Install the package

npm i @openpesa/pesa-js

Add the

src/app.js

const express = require('express');
const { Pesa } = require('@openpesa/pesa-js');

const app = express();
const port = 3000;

// Populate the credentials
const api_key = 'your_api_key';
const public_key = 'the_public_key';
let pesa = new Pesa({ api_key, public_key }, 'sandbox');

app.get('/', (req, res) => {
    res.send('Hello World!');
});

app.get('/pay', (req, res) => {
    // Setup the transaction
    let data = {
        input_Amount: req.body.ammount,
        // ..
    };

    // Execute the transaction
    pesa.c2b(data)
        .then((data) => {
            // Print results
            console.log(data);
            res.send('success');
        })
        .catch((e) => {
            console.log('err: ' + e);
            res.send('error: failed');
        });
});

app.listen(port, () => {
    console.log(`Example app listening at http://localhost:${port}`);
});

curl -X POST -H 'Content-Type: application/json' -d '{"ammount": "1234"}' http://localhost:3000/pay