Скачать или смотреть Solving the AssertionError: 404 != 200 in Django Rest Framework Unit Tests

A guide to troubleshoot the common assertion error while updating user details in Django Rest Framework unit tests by setting URL paths correctly.
---
This video is based on the question https://stackoverflow.com/q/73248088/ asked by the user 'Naveen Pandia' ( https://stackoverflow.com/u/19619966/ ) and on the answer https://stackoverflow.com/a/73249931/ provided by the user 'Metalgear' ( https://stackoverflow.com/u/12965562/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: DjangoRestFramework: Unit Testing AssertionError: 404 != 200 while Test update

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Understanding and Resolving the AssertionError: 404 != 200 in Django Rest Framework Unit Testing

When writing unit tests for your Django Rest Framework APIs, encountering errors can be frustrating, especially when you’re just getting started. One common issue that developers face is the AssertionError: 404 != 200, particularly when trying to update user data. In this guide, we'll break down this error and provide solutions that can help you get back on track.

The Problem: AssertionError in API Testing

While attempting to run tests to update user details within your API, you may come across an AssertionError which indicates that the expected HTTP status of 200 (OK) was not returned. Instead, a 404 (Not Found) error is raised. This typically happens due to incorrect URL paths or missing objects in the database.

Common Causes

Incorrect URL Paths: Your test may refer to an endpoint that does not exist due to improper URL mapping.

Non-existing Resource: If you're trying to update a user that isn't in the database, it will throw a 404 error.

The Solution: Fixing the URL and Test Methods

The key to solving this is ensuring that your URL paths are set and referenced correctly in your test cases. Let’s go through the necessary steps and changes you can make:

Step 1: Define URL Names in urls.py

It’s a good practice to assign names to your URL patterns. This makes them easier to reference in your tests. For your update user functionality, modify your urls.py like this:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Reference URLs in the Test Class

Now, in your test class, utilize the named URLs instead of hardcoding them. Here's how your test class should look:

[[See Video to Reveal this Text or Code Snippet]]

Key Changes Explained

Using reverse: This function constructs the URL based on the name you provide (customer_info_detail_view), ensuring you consistently reference the correct endpoint.

Passing kwargs to reverse: When updating, you need to specify the primary key (pk) for the user you want to update. This is done using kwargs while calling reverse.

Conclusion

By ensuring that your URLs are correctly named and referenced, you can avoid the common 404 vs 200 assertion errors in your Django Rest Framework tests. Testing APIs can be challenging, but with proper routing and testing practices, you can build more robust applications with confidence.

Now you can move forward implementing tests in Django Rest Framework without fear of common pitfalls like the AssertionError. Happy coding!