> ## Documentation Index
> Fetch the complete documentation index at: https://docs.loadforge.com/llms.txt
> Use this file to discover all available pages before exploring further.

# NextJS Load Test

> A premade example for how to load test your NextJS website and understand its performance.

## Overview

In this guide, we'll walk through creating a load test for a Next.js website using Locust, and running it with LoadForge.
This specific test can be used with any JavaScript-based site (next, nuxt, react, etc) as it automatically crawls
URLs on the site and uses those in the load test.

<Note title="More Advanced Testing">
  You can authenticate, maintain sessions, and much more with LoadForge. Browse the docs for examples on what you need, or use your LoadForge account's
  wizard or AI test generator to make the test for you.
</Note>

## Prerequisites

Ensure you have:

* Very basic understanding of Python.
* Have set up a [LoadForge](https://loadforge.com) account.
* Have added and verified your Host for testing

## Using BS4

LoadForge instances come pre-provisioned with many helpful tools, including beautifulsoup4, which we use for parsing html content in this test.
You can install it yourself locally if you are busy developing your test with the following command:

```bash theme={null}
pip install locust beautifulsoup4
```

## Creating Your Test File

The example below demonstrates a user that crawls a webpage, discovering and loading linked pages and static content (like images, CSS, JS files). You
can paste this locustfile directly into LoadForge to test your site.

```python theme={null}
from bs4 import BeautifulSoup
from locust import HttpUser, task, between

class WebsiteUser(HttpUser):
    wait_time = between(1, 2.5)
    
    def on_start(self):
        self.crawl("/")
    
    def crawl(self, path):
        response = self.client.get(path, name="[Page] "+path)
        if response.status_code == 200:
            soup = BeautifulSoup(response.text, "html.parser")
            
            # Discover linked pages
            links = [a["href"] for a in soup.find_all("a", href=True)]
            for link in links:
                self.crawl(link)
            
            # Load static content (img, css, js)
            resources = [(link["href"], "CSS") for link in soup.find_all("link", href=True)]
            resources += [(script["src"], "JS") for script in soup.find_all("script", src=True)]
            resources += [(img["src"], "IMG") for img in soup.find_all("img", src=True)]

            for resource, res_type in resources:
                self.client.get(resource, name=f"[{res_type}] {resource}")

    
    @task(1)
    def load_homepage(self):
        self.client.get("/")
```

## Notes on the script

* `on_start`: Initiates crawling the homepage once per simulated user.
* `crawl`: A recursive method making GET requests to paths, discovering and loading other linked resources.
* `@task(1)`: Simulates users continually loading the homepage.

## Conclusion

This guide provided a basic setup for load testing a Next.js website, crawling, and discovering links/resources. Ensure to optimize and adjust your locustfile based on real-world user interactions, website structure, and testing objectives.

***

<Note title="Did You Know?">
  LoadForge operates on the robust foundation of Locust. This compatibility ensures that users of open-source Locust can effortlessly adopt this script into their setups. If you're already leveraging Locust, think about integrating your script with [LoadForge](https://loadforge.com) to elevate your testing experience!
</Note>