Set up an Express server, install the Infobip API, Axios, and Dotenv. Create an endpoint that accepts the recipient's number and message text. Use Axios to send a POST request to the Infobip API with the necessary headers and message body. Don't forget to securely manage API keys with Dotenv.

An Infobip delivery report webhook is a mechanism that allows your application to receive real-time updates on the status of sent SMS messages. Infobip sends POST requests to a specified URL in your application whenever the delivery status of a message changes. This setup enables automatic tracking without needing to poll the Infobip API.

Node.js, with its non-blocking, event-driven architecture, and Express.js, a lightweight and flexible framework, provide a suitable environment for handling real-time callbacks efficiently. The combination makes it easier to build a server capable of receiving and processing concurrent delivery report updates without blocking other operations.

Configure the Infobip webhook immediately after setting up your /delivery-report endpoint. This ensures your application is ready to receive delivery reports as soon as you start sending SMS messages. Make sure the endpoint URL is publicly accessible, especially during local development using tools like ngrok.

Create a dedicated endpoint (e.g., /delivery-report) in your Express app. Configure this URL as the webhook in your Infobip account settings. Infobip will send POST requests to this endpoint with delivery status updates. Ensure your endpoint always returns a 2xx HTTP status code, even if processing fails, to prevent Infobip retries.

Wrap the logic within your /delivery-report endpoint in a try-catch block to handle potential errors during report processing. Always send a 200 OK response back to Infobip, even if an error occurs, to prevent retry attempts. Log any errors that occur during processing for debugging and analysis.

The messageId is a unique identifier assigned by Infobip to each SMS message sent through their API. It is crucial for tracking the delivery status of individual messages as it's included in the delivery reports sent to your webhook. This ID allows correlating delivery updates with specific messages initiated by your application.

Acknowledging Infobip callbacks with a 2xx HTTP status code, preferably 200 OK, is crucial to prevent Infobip from repeatedly sending the same delivery report. Without proper acknowledgment, Infobip assumes the report wasn't received and will retry at increasing intervals, potentially overwhelming your server.

The guide uses Node.js with Express for the backend, the Infobip API for sending SMS and configuring webhooks, Axios for making HTTP requests, and Dotenv for managing environment variables. These technologies provide a foundation for building a robust SMS application capable of receiving real-time delivery status updates.

Create a project directory, initialize npm with npm init -y, and install necessary packages like express, axios, and dotenv using npm install. Configure environment variables (API key, base URL) in a .env file. Set up a basic Express server and define routes for sending SMS and receiving delivery reports.

ngrok creates a secure tunnel that exposes your locally running application to the public internet. This is essential for receiving webhooks from Infobip during development, as Infobip needs a publicly accessible URL to send delivery reports to. Use ngrok to provide Infobip with a temporary public URL to your local server.

Use a tool like ngrok to expose your local server. Configure the ngrok URL as your webhook endpoint in Infobip. Then, send a test SMS through your application. Infobip will send the delivery report to your ngrok URL, which forwards it to your local server. You can also simulate callbacks using curl.

Log into your Infobip account portal. The API key and base URL are typically located in the Developers or API Keys section. Create a new API key or use an existing one. The base URL is specific to your account and is essential for directing API requests to the correct instance.

For sending messages, implement retry logic in your application. If the initial request to the Infobip API fails, implement exponential backoff – wait for increasing durations before retrying. Don't retry for client-side errors (4xx). For callbacks, Infobip handles automatic retries, so ensure your endpoint returns a 200 OK response quickly.