Alba 6.0 is friendly with .Net 6, Minimal API, and WebApplicationFactory

Alba is a small open source library that is a helper for integration testing against ASP.Net Core HTTP methods that makes the underlying ASP.Net Core TestServer easier and more declarative to use within tests.

Continuing a busy couple weeks of OSS work getting tools on speaking terms with .Net 6, Alba v6.0 was released early this week with support for .Net 6 and the new WebApplication bootstrapping model within ASP.Net Core 6.0. Before I dive into the details, a big thanks to Hawxy who did most of the actual coding for this release.

The biggest change was getting Alba ready to work with the new WebApplicationBuilder and WebApplicationFactory models in ASP.Net Core such that Alba can be used with any typical way to bootstrap an ASP.Net Core project. See the Alba Setup page in the documentation for more details.

Using Alba with Minimal API Projects

From Alba’s own testing, let’s say you have a small Minimal API project that’s bootstrapped like this in your web services Program file:

using System;
using Microsoft.AspNetCore.Builder;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

var app = builder.Build();

// Configure the HTTP request pipeline.

app.UseHttpsRedirection();


app.MapGet("/", () => "Hello World!");
app.MapGet("/blowup", context => throw new Exception("Boo!"));

app.Run();

Alba’s old (and still supported) model of using the application’s HostBuilder in the .Net 5 project templates is no help here, but that’s okay, because Alba now also understand how to use WebApplicationFactory to bootstrap the application shown above. Here’s some sample code to do just that in a small xUnit test:

// WebApplicationFactory can resolve old and new style of Program.cs
// .NET 6 style - the global:: namespace prefix would not be required in a normal test project
await using var host = await AlbaHost.For<global::Program>(x =>
{
    x.ConfigureServices((context, services) =>
    {
        services.AddSingleton<IService, ServiceA>();
    });
});

host.Services.GetRequiredService<IService>().ShouldBeOfType<ServiceA>();

var text = await host.GetAsText("/");
text.ShouldBe("Hello World!");

And you’re off to the races and authoring integration tests with Alba!

How Alba and ASP.Net Have Evolved

The code that ultimately became Alba has been around for over a decade, and I think it’s a little interesting to see the evolution of web development in .Net through Alba & I’s history.

1998: I built a couple internal, “shadow IT” applications for my engineering team with ASP “classic” and fell in love with web development

2003: I was part of a small team building a new system on the brand new ASP.Net WebForms application model and fell out of love with web development for several years

2008-2014: In the heady days of ALT.Net (and with the opening provided by ASP.Net MVC to finally consider alternatives to the abomination that was WebForms) I was the lead of the alternative web framework in .Net called FubuMVC. What is now “Alba” started as a subsystem within FubuMVC itself that we used to test fubu’s content negotiation subsystem completely in memory without having to run a web server.

~2015: I ripped Alba into its own library and ported the code to work against the OWIN model

2017: Alba 1.0 was ported to the new ASP.Net Core, but used its own special sauce to run HTTP requests in memory with stubbed out HttpContext objects

2018: Alba 2.0 accommodated a world of changes from the release of ASP.Net Core 2.*. There was temporarily separate Nugets for ASP.Net Core 1 and ASP.Net Core 2 because the models were so different. That sucked.

2019: Alba 3.0 was released supporting ASP.Net Core 3.*, and ditched all support for anything on the full .Net framework. At this point Alba’s internals were changed to utilize the ASP.Net Core TestServer and HostBuilder models

2020: Alba 4.0 supported ASP.Net Core 5.0

August 2021: Alba 5.0 added a new extension model with initial extensions for testing applications secured by JWT bearer tokens

December 2021: .Net 6 came with a lot of changes to the ASP.Net Core bootstrapping model, so here we are with a brand new Alba 6.0.

Lots and lots of changes in the web development world within .Net, and I’m betting that’s not completely done changing. For my part, Alba isn’t the most widely used library, but there’s more than enough usage for me to feel good about a piece of fubumvc living on. Plus we use it at work for integration testing, so Alba is definitely going to live on.