Creating a Locust Loadtest with Flask

Creating a Locust Loadtest with Flask

Screencast

One powerful way to create a simple loadtest is with Locust and Flask. Here is an example of a simple flask hello world app. The entire source code is found here.

from flask import Flask
app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'

if __name__ == "__main__":
    app.run(host='0.0.0.0', port=8080, debug=True)

The loadtest file is very simple to configure. Notice the index function calls into the main, and only flask route.

from locust import HttpLocust, TaskSet, between

def index(l):
    l.client.get("/")

class UserBehavior(TaskSet):
    tasks = {index: 1}

class WebsiteUser(HttpLocust):
    task_set = UserBehavior
    wait_time = between(5.0, 9.0)

The login screen requires the number of user and also hostname and port. In our case this will be the port 8080.

You can see how locust works when it runs.