integration-testing

name	integration-testing
description	Guidelines for cross-layer testing (Hooks + UI + Services) using real logic and MSW for network interception.

Integration Testing Skill (BackEnd)

This skill defines how to implement and organize integration tests that validate the interaction between Endpoints, Services, and the Database.

Core Principle: "Real Logic & Infrastructure"

Unlike unit tests that mock dependencies, integration tests in FinanzApp Backend use:

1. Real Controllers: Calls to WebAPI/Endpoints/ are executed via HttpClient.
2. Real Services: Business logic in Services/ is executed fully.
3. WebApplicationFactory: Spin up a test server in memory to handle real API requests.
4. In-Memory DB / SQLite: Use a lightweight DB provider to test persistence without external SQL Server dependency.
5. Mocked Third-Party APIs: Use Moq or a mock server (like WireMock.Net) to intercept external calls (CoinGecko, Yahoo Finance).

Organization

All integration tests MUST be located in the global tests directory:

• Path: Tests/Integration/[Module]/[Feature]IntegrationTests.cs

Guidelines

1. Scope: Test full business flows (e.g., Create Operation -> Calculate Portfolio Valuations -> Verify DB Persisted).
2. External Mocks: Isolate external infrastructure (Mail, Storage, AI) using Moq while keeping core internal logic untouched.
3. State Management: Ensure the database is reset or uses a fresh directory/name between test runs to ensure isolation.
4. Auth Simulation: Use a custom AuthenticationHandler or a test JWT generator to simulate authenticated requests.

Example

// Tests/Integration/Auth/LoginFlowTests.cs
[Fact]
public async Task Login_ValidCredentials_ReturnsTokenAndUser()
{
    // 1. Arrange: Prepare client and mock dependencies if needed
    var client = _factory.CreateClient();
    var loginDto = new LoginDto { Email = "[e-mail]", Password = "Password123" };

    // 2. Act: Call the real API endpoint
    var response = await client.PostAsJsonAsync("/api/auth/login", loginDto);

    // 3. Assert: Verify status code and content
    response.EnsureSuccessStatusCode();
    var result = await response.Content.ReadFromJsonAsync<LoginResultDto>();
    Assert.NotNull(result.Token);
    Assert.Equal("Agus", result.User.Name);
}