How to Mock User.Identity in ASP.NET Core for Testing Controllers

Learn how to effectively `mock User.Identity` in your ASP.NET Core controllers to test methods accurately. This guide provides a detailed explanation and example code to help you achieve this with ease.
---
This video is based on the question https://stackoverflow.com/q/68888780/ asked by the user 'SLAYER' ( https://stackoverflow.com/u/16730776/ ) and on the answer https://stackoverflow.com/a/68889777/ provided by the user 'aamd' ( https://stackoverflow.com/u/1966784/ ) 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: How mock User.Identity

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

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Mocking User.Identity in ASP.NET Core Controllers

When it comes to unit testing in ASP.NET Core, one common challenge developers face is the need to mock the user identity in the context of a controller. This is particularly necessary when the controller methods depend on the User.Identity.Name property, which determines what actions can be performed based on the logged-in user. In this guide, we will explore how you can easily mock User.Identity within your tests to ensure your controller methods are working as intended.

Understanding the Problem

In our sample scenario, we have a CardController that checks for the existence of a card by public ID and queries the repository for data. The method CheckPublicID uses User.Identity.Name, which means that when we run our unit tests, we need to simulate an authenticated user in order to get accurate results.

Here’s the essential part of our CardController code:

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

The important question arises: How can we mock User.Identity.Name for our unit tests? Let's explore the solution.

Step-by-Step Solution

To mock User.Identity, we need to set up a fake HttpContext that simulates an authenticated user. Here’s how to do this:

1. Create a Mock HttpContext

First, you'll need to create a DefaultHttpContext and set a ClaimsPrincipal (which represents the user) with the identity you want. Here’s an example:

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

This will set the User.Identity.Name to "TestUser".

2. Set Up the Action Context

Next, you need to create an ActionContext that provides routing data and action descriptor information to the controller:

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

3. Assign the Controller Context

Now, you can assign the constructed actionContext to your CardController like so:

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

4. Complete the Unit Test

Here's how your unit test might look all put together:

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

Conclusion

Mocking User.Identity allows you to create effective unit tests for your ASP.NET Core controllers. By using a DefaultHttpContext and setting a mock ClaimsPrincipal, you can easily simulate authorized users in your testing environment. This technique not only enhances the robustness of your tests but also promotes better software design by allowing for more isolated unit testing scenarios.

With this implementation, you can now ensure that your controller's behavior aligns with the expectations based on the current user's identity.

Feel free to reach out if you have any questions or need further assistance with your ASP.NET Core testing needs!

Видео How to Mock User.Identity in ASP.NET Core for Testing Controllers канала vlogize