Automated Testing Strategies for ASP.NET Core

Getting Started

You should set both the Api and the WebApp projects as startup projects. In Visual Studio this can be done by "Configure Startup Projects", then choosing "Multiple startup projects", and finally choosing the Launch-UI-and-API profile.

The solution uses two services that it expects to be running locally. The simplest way to run these services is to use Docker. The following commands will start the services.

docker pull rnwood/smtp4dev
docker run --rm -d --name fakemail -p 3000:80 -p 2525:25 rnwood/smtp4dev

docker pull datalust/seq
docker run --name seq -d --restart unless-stopped -e ACCEPT_EULA=Y -p 5341:80 datalust/seq

Even without them running you should be able to run the solution.

To see logs, you can navigate to http://localhost:5341.

To see emails, you can navigate to http://localhost:3000.

Features

This is a simple e-commerce application that has a few features that we want to explore automated testing strategies for.

Here are the features:

• API
  • GET based on category (or "all") and by id allow anonymous requests
  • POST requires authentication and an admin role
  • Validation will be done with FluentValidation and errors returned as a 400 Bad Request with ProblemDetails
  • A GET with a category of something other than "all", "boots", "equip", or "kayak" will return a 500 internal server error with ProblemDetails
  • Data is refreshed to a known state as the app starts
• Authentication provided by OIDC via the demo Duende Identity Server
• A custom claims transformer will add the admin role to "Bob Smith" and any authentication via Google
• WebApp
  • The home page and listing pages will show a subset of products
  • There is a page at /Admin that will show a list of products that can be edited or added to
  • If you navigate to /Admin without the admin role, you should see an AccessDenied page
  • Any validation errors from the API should be displayed on the admin section edit pages
  • Can add items to cart and see a summary of the cart (shows when empty too)
  • Can submit an order or cancel the order and clear the cart
  • A submitted order will send a fake email

"Catch" with a refactoring change:

• change the "admin" role to be "administrator" and see what breaks (maybe make it a different claim type than role and change to a "policy"??)

For the learner:

• Add edit and (soft) delete to the API and WebApp, then write tests
• More complex "cart edit" functionality
• Be able to apply a "promotion" on the Cart page

VS Code Setup

RUnning in VS Code is a totally legitimate use-case for this solution and repo.

The same instructions above (Getting Started) apply here, but the following extension should probably be installed (it includes some other extensions):

• C# Dev Kit

Then run the API project and the UI project.

Data and EF Core Migrations

The dotnet ef tool is used to manage EF Core migrations. The following command is used to create migrations (from the CarvedRock.Data folder).

dotnet ef migrations add Initial -s ../CarvedRock.Api

The initial setup for the application uses SQLite. The data will be stored in a file called carvedrock-sample.sqlite as defined in the API project's appsettings.json file.

The location of the file is in the "local AppData" folder (Environment.SpecialFolder.LocalApplicationData):

• Windows: C:\Users\<username>\AppData\Local\
• Mac: /Users/USERNAME/.local/share

To browse / query the data, you can use some handy extensions:

• In Visual Studio, use the SQLite and SQL Server Compact Toolbox extension
• In VS Code, use the SQLite Viewer extension

Switching Databases

Switching between SQLite and Postgres and SQL Server is a matter of commenting out the unused dbcontext setup / initialization logic and commenting in what you want:

• Program.cs of the API project
• CustomApiFactory.cs of the InnerLoopTests project
• SharedFixture.cs of the InnerLoopTests project

You also need to manually delete the CarvedRock.Data.Migrations folder and recreate the migrations using the instructions above.

Running Postgres for local development:

docker pull postgres
docker run -d --name carvedrock-postgres -e POSTGRES_PASSWORD=carvedrock -p 5432:5432 postgres

Running SQL Server for local development:

docker pull mcr.microsoft.com/mssql/server
docker run -d --name carvedrock-sqlserver -e "ACCEPT_EULA=Y" -e "SA_PASSWORD=Carvedr0ck!" -p 1433:1433 mcr.microsoft.com/mssql/server

Verifiying Emails

The very simple email functionality is done using a template from this GitHub repo and the smtp4dev service that can easily run in a Docker container.

There is a UI that you can naviagte to in your browser for seeing the emails that works great. If you use the docker run command that I have listed above, the UI is at http://localhost:3000.

There is also an API that is part of that service and a couple of quick API calls call give you the content of the email body that you want to verify:

GET http://localhost:3000/api/messages

### find the ID of the message you care about

GET http://localhost:3000/api/messages/<message-guid>/html

Test Coverage

To see test coverage for the inner loop tests you've written, you can use the default coverlet tool that is included with the XUnit test project template.

dotnet test --collect:"XPlat Code Coverage"

Then use the reportgenerator global tool to generate an HTML report. To install the tool (you only need to do this once):

dotnet tool install --global dotnet-reportgenerator-globaltool

Then run the following command to generate the report:

reportgenerator -reports:".\Tests\**\TestResults\**\coverage.cobertura.xml" -targetdir:"coverage" -reporttypes:Html

To remove any contents from previous runs, use the following PowerShell command:

gci -include TestResults,coverage -recurse | remove-item -force -recurse

AngleSharp and UI Selectors

• AngleSharp
• Selectors Reference