Skip to main content

Worldline Webhooks

This guide covers how to use ngrok to integrate your localhost app with Worldline by using Webhooks. Worldline webhooks can be used to notify an external application whenever specific events occur in your Worldline account.

By integrating ngrok with Worldline, you can:

  • Develop and test Worldline webhooks locally, eliminating the time in deploying your development code to a public environment and setting it up in HTTPS.
  • Inspect and troubleshoot requests from Worldline in real-time via the inspection UI and API.
  • Modify and Replay Worldline Webhook requests with a single click and without spending time reproducing events manually in your Worldline account.
  • Secure your app with Worldline validation provided by ngrok. Invalid requests are blocked by ngrok before reaching your app.

Step 1: Start your app

For this tutorial, we'll use the sample NodeJS app available on GitHub.

To install this sample, run the following commands in a terminal:

git clone
cd ngrok-webhook-nodejs-sample
npm install

This will get the project installed locally.

Now you can launch the app by running the following command:

npm start

The app runs by default on port 3000.

You can validate that the app is up and running by visiting http://localhost:3000. The application logs request headers and body in the terminal and responds with a message in the browser.

Step 2: Launch ngrok

Once your app is running successfully on localhost, let's get it on the internet securely using ngrok!

  1. If you're not an ngrok user yet, just sign up for ngrok for free.

  2. Download the ngrok agent.

  3. Go to the ngrok dashboard and copy your Authtoken.
    Tip: The ngrok agent uses the auth token to log into your account when you start a tunnel.

  4. Start ngrok by running the following command:

    ngrok http 3000
  5. ngrok will display a URL where your localhost application is exposed to the internet (copy this URL for use with Worldline). ngrok agent running

Step 3: Integrate Worldline

To register a webhook on your Worldline account follow the instructions below:

  1. Access Worldline and sign in using your Worldline account.

  2. On the left menu, click Developer and then click Webhooks.

  3. On the Webhooks page, click Create a Webhook.

  4. On the Webhooks page, click Generate webhook keys and make note of the Secret Webhook Key field value.

  5. Click Add webhook endpoint, enter the URL provided by the ngrok agent to expose your application to the internet in the Endpoint URL field (i.e., and then click Confirm. Worldline webhook URL

Run Webhooks with Worldline and ngrok

Worldline sends different request body contents depending on the event that is being triggered. You can trigger a test call from Worldline to your application by following the instructions below.

  1. In the same browser, click Payment links on the left menu and then click Generate link.

  2. On the Generate link page, enter a value in the Amount and Order reference fields, and then click Generate link.

  3. On the Share link page, click the copy icon close to the payment link, paste this link to a new browser tab, select Bancontact as the payment method, and then click Cancel.

    Confirm your localhost app receives post request notifications and logs both headers and body in the terminal.

Inspecting requests

When you launch the ngrok agent on your local machine, you can see two links:

  • The URL to your app (it ends with for free accounts or for paid accounts when not using custom domains)
  • A local URL for the Web Interface (a.k.a Request Inspector).

The Request Inspector shows all the requests made through your ngrok tunnel to your localhost app. When you click on a request, you can see details of both the request and the response.

Seeing requests is an excellent way of validating the data sent to and retrieved by your app via the ngrok tunnel. That alone can save you some time dissecting and logging HTTP request and response headers, methods, bodies, and response codes within your app just to confirm you are getting what you expect.

To inspect Worldline's webhooks call, launch the ngrok web interface (i.e., and then click one of the requests sent by Worldline.

From the results, review the response body, header, and other details:

ngrok Request Inspector

Replaying requests

The ngrok Request Inspector provides a replay function that you can use to test your code without the need to trigger new events from Worldline. To replay a request:

  1. In the ngrok inspection interface (i.e. http://localhost:4040), select a request from Worldline.

  2. Click Replay to execute the same request to your application or select Replay with modifications to modify the content of the original request before sending the request.

  3. If you choose to Replay with modifications, you can modify any content from the original request. For example, you can modify the id field inside the body of the request.

  4. Click Replay.

Verify that your local application receives the request and logs the corresponding information to the terminal.

Secure webhook requests

The ngrok signature webhook verification feature allows ngrok to assert that requests from your Worldline webhook are the only traffic allowed to make calls to your localhost app.

Note: This ngrok feature is limited to 500 validations per month on free ngrok accounts. For unlimited, upgrade to Pro or Enterprise.

This is a quick step to add extra protection to your application.

  1. Restart your ngrok agent by running the command, replacing {your webhook secret} with the value of the Secret Webhook Key (See Integrate ngrok and Worldline.):

    ngrok http 3000 --verify-webhook worldline --verify-webhook-secret {your webhook secret}
  2. Access Worldline, sign in, create a new payment link, open the link in a new browser tab, and select Bancontact as the payment method.

Verify that your local application receives the request and logs information to the terminal.