Locust in Python

Rana Hasnain Khan Oct 10, 2023
Locust in Python

We will introduce locust in Python with an example.

Locust in Python

Locust is used for load testing in Python. It is a very useful and best tool for load testing in Python.

We can put a certain load on the system to test how much load a system can handle using a locust.

We can also use locust to target the websites that contain load testing and check the management power of the system and how many daily active users it can handle. The tool acts as a swarm of locusts that attack the target, a website or a system.

The behavior of each locust in a swarm can be customized or changed, and we can also track the swarming process in real-time via a web interface. Load and software testing is one of the main steps in software development.

Every website or software is tested to check how much load it can handle. The load a software can handle determines how well it can perform under the load.

Now we will discuss the installation process of locust and how it can be used to test the performance of websites. We can install the locust by using the following command.

pip install locust

Once we have installed the locust, we can use it for testing a website. Now, let’s use it in our example in which we will create a Python server to server the flask pages.

We can customize the server to serve the pages from any folder. We can also use it to test our web application and debug using the locust.

We will use locust as a web crawler to crawl web pages and extract the information we want. We will also use locust as a framework to build our own web crawling agents. Let’s get started.

Now, let’s create a new file,, the flask development file used for load testing. It will contain the following code as shown below.

# python
from flask import Flask


app = Flask(__name__)

def Text():

    return "Text"

if __name__ == "__main__":"", port=PORT_NUMBER)


When we run this code, it will open a page at localhost:2000/. This page will display the Text that we returned in our above Text() function.

So in this way, we can use the locust in our applications.

Rana Hasnain Khan avatar Rana Hasnain Khan avatar

Rana is a computer science graduate passionate about helping people to build and diagnose scalable web application problems and problems developers face across the full-stack.