Unit testing is an essential part of software development and Django offers a solid in-built testing framework to make this process more efficient. Django’s testing framework is built on top of Python’s native unittest module and enables you to create a series of tests for your application that ensures your code is performing as expected.
To get started with unit testing in Django, you need to create a test case. A test case is a set of conditions under which a tester will determine whether an application, software system or one of its features is working as it was originally established to do. Here is a sample of how to do it.
```
from django.test import TestCase
from .models import YourModel
class YourModelTest(TestCase):
def test_string_representation(self):
yourmodel = YourModel(title=“Some text”)
self.assertEqual(str(yourmodel), yourmodel.title)
```
In this example, we import Django’s TestCase module as well as the model to be tested. In our test case (YourModelTest), we have one method: test_string_representation. This method creates an instance of YourModel and then checks that its string representation is correctly configured.
You would include this test case in a file within your app directory, commonly named ‘tests.py’. To run your test, you would navigate to your project directory in the terminal and then run:
python manage.py test
And if everything is configured correctly, Django’s test runner will discover the test case and execute it.
To improve the efficiency of your tests, Django provides some additional tools for unit testing. Django test client for example, a Python class that acts as a dummy Web browser, allowing you to test your views and interact with your Django-powered application programmatically. This class allows you to:
- simulate GET and POST requests
- observe the output (content, status code, headers)
- send cookies along with requests
Another tool that Django provides for testing is the RequestFactory. Unlike the test Client, RequestFactory doesn’t enforce middleware: this makes RequestFactory faster but also means that some parts of the request/response cycle won’t be handled (like rendering of templates).
It’s essential that your application handles both the expected and unexpected inputs including edge and corner cases which means testing everything. When all these tests pass, that’s when you’ll know your code is ready to be launched.
For further details, you can always refer to the Django official documentation: https://docs.djangoproject.com/en/3.1/topics/testing/overview/
References:
- Django official documentation on testing (https://docs.djangoproject.com/en/3.1/topics/testing/overview/)
- Practical Django Testing Examples by Kevin Harter (https://www.kevinharter.fr/blog/2019/01/09/practical-django-testing-examples/)
