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Pavan Belagatti
Pavan Belagatti

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Learn How to Test Flask Applications with Pytest

Welcome to this tutorial on how to test Flask applications with Pytest. Flask is a popular web framework in Python that allows developers to build web applications quickly and easily. However, as your application grows in complexity, ensuring that your code is reliable and bug-free becomes increasingly important. That's where testing comes in. Pytest is a powerful and popular testing framework in Python that makes it easy to write and run tests for your Flask application. In this tutorial, you will learn how to automate tests for your Flask application using Pytest, and how to ensure that your code is robust and error-free. So let's get started!



First, sign in to your Harness account. Harness is a continuous delivery platform.
signup Harness

Get started with creating your first pipeline
first pipeline

Authenticate with your GitHub account as your application code is present there.
add github

authenticate with GitHub

Select your application repository. The Flask application you forked above.
select repo

Select 'Python' from the list and start configuring the pipeline. The right side in the below screenshot you see is a default yaml configuration of your pipeline.
configure pipeline

Once you continue, you will land on the pipeline studio which looks as below
pipeline studio

Click on 'Build Python App' and you should see the step configured under the execution.
build python app

When you click on the 'Build Python App' step under execution, you will see the commands used.
build python

Don't change anything. Apply changes, save and run the pipeline.
run pipeline

You should see a successful pipeline execution:)
pipeline execution

Your pipeline is all automated to run tests whenever any developer pushes code to the main branch.
You can verify this by going to the 'Triggers' tab from the pipeline studio.
Triggers tab

You can see push and pull triggers already configured for you.
pull and push triggers

Let's push some code to the main branch.
As soon as you push the code, the build gets triggered and you can see the same below.
build triggered

Congratulations! We just configured an automated CI pipeline for our Flask application.

This way, you can easily automate your tests and complete pipeline tasks. Also, you can see who pushed the last changes and what code they pushed.

Check out my other article to learn about automating tests for your Node.js applications.

Top comments (2)

windyaaa profile image
Windya Madhushani

Nice article.

sectasy0 profile image

Nice material, but in my opinion, an example with actual application testing was missing here. The title is a bit misleading