BookStoreAPI_xUnitTesting

Overview

A .NET Core Web API for a bookstore with unit, integration, and end-to-end (E2E) tests.

Features

• BookStore Web API: A basic RESTful API built with ASP.NET Core.
• Unit Testing: Focus on isolated functionality of API Controllers using xUnit and FluentAssertions.
• Integration Testing: Uses an in-memory database to simulate real-world interactions between repository layer and the database.
• End-to-End (E2E) Testing: Employed TestContainers with an MSSQL instance to replicate a full back-end system test.

Technologies Used

• ASP.NET Core Web API: Core web API framework.
• Entity Framework Core: Data access technology(O/RM) for the repository layer.
• xUnit: Test framework for unit and integration testing.
• FluentAssertions: Provides readable assertions to improve test clarity and debugging.
• FakeItEasy: Dynamic fake framework for creating all types of fake objects, mocks, stubs etc.
• In-memory Database: For lightweight integration testing without external dependencies.
• TestContainers (MSSQL): Containers used for end-to-end testing to simulate real-world databases.
• SwaggerUI: For visualizing and interacting with the API’s resources/endpoints.

Setting Up

Prerequisites

• .NET SDK
• Docker (for E2E tests with TestContainers)

Installation

1. Clone the repository:

   git clone https://github.com/OzturkVedat/BookStoreAPI_xUnitTesting.git
   cd BookStoreAPI_xUnitTesting

2. Restore the .NET dependencies:

   dotnet restore

3. Build the project:

   dotnet build

4. Set up database: Create a local database, MSSQL container, etc to connect the API. Modify the connection string in appsettings.json. To apply migrations:

   dotnet ef database update

   To create migrations (if there's none for current db schema):

   dotnet ef migrations add <migration-name>

5. Run the API:

   dotnet run --project ./src/BookStoreBackend

Running Tests

The project contains unit, integration, and E2E tests. You can run them using the .NET CLI, or more practically, you can run them on Visual Studio's test explorer like this:

Project Structure

BookStoreAPI_xUnitTesting/
├── BookStoreBackend/
│       ├── Controllers/
│       ├── Data/
│       ├── Interfaces/        # Abstractions for repositories
│       ├── Middleware/        # Custom middleware for global error handling
│       ├── Migrations/        # EF Core Migration files
│       ├── Models/
│       ├── Repository/        # Repository pattern implementations
│       ├── appsettings.json/  # Configuration settings
│       └── Program.cs
├── BookStoreBackend.Tests/
│   ├── ControllerTests/
│       ├── AuthorControllerE2E.cs
│       ├── AuthorControllerUnit.cs
│       ├── BookControllerE2E.cs
│       └── BookControllerUnit.cs
│   ├── RepositoryTests/
│       ├── AuthorRepositoryIntegration.cs
│       └── BookRepositoryIntegration.cs
│   └── TestUtilities/
│       ├── CommonAssertions.cs            # Reusable assertion methods
│       ├── E2ETestBase.cs                 # Base setup for E2E tests
│       ├── E2ETestDbFactory.cs            # Factory for TestContainers
│       └── IntegrationTestFixture.cs      # Setup/teardown for integration tests
├── .gitignore
├── .BookStoreBackend.sln
└── README.md         # Project documentation

Testing Strategies

All three tests use xUnit framework and FluentAssertions primarily.

Unit Testing

Written to validate individual functionalities of API controller endpoints in isolation. These tests use FakeItEasy for mocking the repository responds and FluentAssertions to validate the results.

Integration Testing

Designed to test the interactions between repository layer and the database. An in-memory database is used to simulate real world database interactions without needing an actual database.

End-to-End (E2E) Testing

Performed to verify the entire system, from endpoints to database. TestContainers is used to spin up an MSSQL container for realistic database interaction in Docker.

Contributing

Feel free to open issues or submit pull requests for improvements, especially around the testing framework or adding new test cases.