---
title: "Function Structure"
url: https://docs.catalyst.zoho.com/en/smartbrowz/help/browser-logic/function-structure/
description: "Code a Catalyst Serverless function to perform any browser task that you would otherwise manually do."
last_updated: 2025-10-09T16:11:25Z
service: SmartBrowz
type: general
---

# Browser Logic Function Structure

When you [create a Browser Logic function](https://docs.catalyst.zoho.com/en/smartbrowz/help/browser-logic/implementation/) from the Catalyst CLI, it is created with a boilerplate code structure as shown below. Catalyst also creates the required dependencies and configuration files for your function and your project. You can refer to the [Project Directory Structure](https://docs.catalyst.zoho.com/en/cli/v1/project-directory-structure/introduction/) help page for details about the general configuration files.

### Java

> **Note:** This boilerplate code below will be present in your function file when you initialize a browser logic function in Java with Selenium

```java
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.json.simple.JSONObject;
import org.openqa.selenium.chrome.ChromeDriver;
import com.catalyst.browserlogic.SeleniumHandler;
public class BrowserlessExample implements SeleniumHandler {
	private static final Logger LOGGER = Logger.getLogger(SeleniumExample.class.getName());
	JSONObject responseData = new JSONObject();
	@Override
	@SuppressWarnings("unchecked")
	public void runner(HttpServletRequest request, HttpServletResponse response,ChromeDriver driver) throws Exception {
		try {
			//Fetches the endpoint and method to which the call was made
			String url = request.getRequestURI();
			String method = request.getMethod();
			driver.get("https://www.example.com");
			responseData.put("message", "Title of the page "+driver.getTitle());
			//Sends the response back to the Client
			response.setContentType("application/json");
			response.getWriter().write(responseData.toString());
			response.setStatus(200);
		} catch (Exception e) {
		//The actions are logged. You can check the logs from Catalyst Logs.
			LOGGER.log(Level.SEVERE, "Exception in SeleniumExample", e);
			responseData.put("error", "Internal server error occurred. Please try again in some time.");
			response.getWriter().write(responseData.toString());
			response.setStatus(500);
		}
	}
}
```

### NodeJS

> **Note:** This boilerplate code below will be present in your function file when you initialize a browser logic function in NodeJS with Puppeteer

```java
module.exports.puppeteer = async (request, response, page) => {
    await page.goto('https://example.com/',{waitUntil: "domcontentloaded"});
    const pageTitle = await page.title();
    response.setHeader('Content-Type', 'application/json');
    response.write(JSON.stringify({ output: pageTitle }));
    response.end();
};
```