---
title: "Configure the Advanced I/O function"
url: https://docs.catalyst.zoho.com/en/tutorials/newsapp/nodejs/configure-advancedio/
description: "Build a web news application that automatically fetches news from a third-party service periodically using the Catalyst Job Scheduling Cron component, and a Job Function and Advanced I/O function coded in Node.js."
last_updated: 2026-08-17T12:16:04Z
service: All Services
type: tutorial
related_links:
  - name: "Advanced I/O Function"
    url: /en/serverless/help/functions/advanced-io
  - name: "Data Store"
    url: /en/cloud-scale/help/data-store/introduction
  - name: "ZCQL"
    url: /en/cloud-scale/help/zcql/introduction
---

# Configure the Advanced I/O Function

The Advanced I/O function directory (`functions/news_app_function`) contains the following files: 

* The `index.js` main function file
* The `catalyst-config.json` configuration file
* Node modules
* [`package.json`](https://docs.npmjs.com/files/package.json) and [`package-lock.json`](https://docs.npmjs.com/configuring-npm/package-lock-json.html) dependency files.

You will be adding code in the `index.js` file.

The Advanced I/O function fetches the news item from its source table in the Data Store and forwards it to the client component as a JSON response.

### Install Express Node.js Framework

Since you are coding in the  Node.js platform, you will be using the [`Express Node.js`](https://expressjs.com/) framework. To import the Express package in the code, you must install the Express dependencies in your system.

```sh
npm install express
```

This will install the Express module and save the dependencies.

![advanced-express](https://catalyst-docs-development.zohostratus.in/images/tutorials/cron/advanced-express.webp)

Copy the Node.js code and paste it in `index.js` in `functions/news_app_function` directory of your project, and save the file. You can use any IDE to work with the application's files.

> **Note**: Please go through the code in this section to make sure you fully understand it.

**index.js**

```javascript
'use strict';
var express = require('express');
var app = express();
var catalyst = require('zcatalyst-sdk-node');
app.use(express.json());
//GET API that gets the news from the required table
app.get('/fetchData', (req, res) => {
	var tablename = req.query.tablename;
	console.log("Table Name "+tablename);
	//Initializing Catalyst SDK
	var catalystApp = catalyst.initialize(req);
	//Queries the Catalyst Data Store table and gets the required news
	getDataFromCatalystDataStore(catalystApp, tablename).then(newsDetails => {
			res.send({
				"content": newsDetails
			})
	}).catch(err => {
		console.log(err);
		sendErrorResponse(res);
	})
});
/**
 * Executes the Query and fetches the news from the table
 * @param {*} catalystApp 
 * @param {*} tablename 
 */
function getDataFromCatalystDataStore(catalystApp, tablename) {
	return new Promise((resolve, reject) => {
		//Queries the Catalyst Data Store table
		catalystApp.zcql().executeZCQLQuery("Select title,url from " + tablename).then(queryResponse => {
			resolve(queryResponse);
		}).catch(err => {
			reject(err);
		})
	});
}
/**
 * Sends an error response
 * @param {*} res 
 */
function sendErrorResponse(res) {
	res.status(500);
	res.send({
		"error": "Internal server error occurred. Please try again in some time."
	});
}
module.exports = app;

```

The Advanced I/O function is now configured. We will discuss the application's architecture after we configure the client.