Andre Hofmeister

Maintaining @testcontainers | Contributing to OSS | Automating builds, tests and infrastructures | Making devs happy | @ZEISS_Group | Docker Captain

[Andre Hofmeister @hovfefe]

Super excited to join the @Docker Captains Program 🎉 Honored to see my work on Testcontainers for .NET (and soon Docker.DotNet) being recognized. Looking forward to contributing to Docker, .NET, and open-source projects with the amazing folks in the program :tc-love:

[Milan Jovanović @mjovanovictech]

No - you aren't doing "integration" testing with an in-memory database.

At best it's a glorified unit test...

I've seen many examples using the EF Core in-memory provider.

This isn't an integration test because there's no real database.

Worse, this will fail to catch any LINQ or SQL bugs.

Here's a better approach:

- Use a real database or Docker container
- Connect to this database from your tests
- Write proper integration tests that have value

If you want to use Docker, I recommend exploring Testcontainers.

It lets you define throwaway containers in your tests.

What tools or methods do you use for integration testing?

[Andre Hofmeister @hovfefe]

Been leaning hard on Docker Sandboxes lately to keep secrets out of my agent environment, no tokens sitting in env vars waiting to leak 🔒.

Put together a spec.yaml workflow that auths against GHE Copilot + a private NuGet feed: https://t.co/txQMMh3UuK.

[Andre Hofmeister @hovfefe]

Testcontainers for .NET 4.12.0 is out 🐳 This release ships a major version bump of our forked Docker.DotNet client, bringing a bunch of improvements made over the past months. Fingers crossed it's all smooth sailing for you 🤞: https://t.co/D5o2tFBrpy.

[Andre Hofmeister @hovfefe]

Along with many stability and performance improvements, the new Docker.DotNet version is now AOT-compatible. Check out the release notes from version 4.0.0 onward. They include many great updates: https://t.co/vABxKABVyk.

[Andre Hofmeister @hovfefe]

@AntonMartyniuk @mjovanovictech > .NET Aspire spins up your ENTIRE distributed system in one test […]

You can do exactly the same with TC. Aspire, though, offers some more convenience when wiring everything together.

[Andre Hofmeister @hovfefe]

@maurelio79 @AlanBarber @mjovanovictech Hmm, maybe I'm misunderstanding something. We are running simple tests on the MS-hosted agents: https://t.co/QVvSAL779X. But it comes with some constraints.

[Andre Hofmeister @hovfefe]

@maurelio79 @AlanBarber @mjovanovictech The .NET implementation also supports Windows containers.

[Milan Jovanović @mjovanovictech]

Testcontainers is hands down the best way to write integration tests in .NET.

You can run your external services in Docker containers, which you can access from your tests.

Here's how to spin up SQL Server in a container. 👇

[Andre Hofmeister @hovfefe]

I've also got an update ready for the Docker.DotNet client, which in the next release will bring performance improvements, better resource usage, lots of fixes, and support for .NET's native HTTP handler 💪.

[Andre Hofmeister @hovfefe]

The new Testcontainers for .NET release has arrived: https://t.co/fF3lU9Osmi. Version 4.11 comes with new modules, bug fixes, and improvements, plus OpenSSF Scorecard analyses for extra trustworthiness.

[Manu of the Rock - 🤖 🎯 🐳 @mdelapenya]

Hey, @testcontainers for #Golang v0.41.0 is out! 🚀

TiDB, Forgejo, Lowkey Vault, and a security fix you should know about.

Full release notes with contributor credits and the complete changelog: https://t.co/kg0HGjHqGx

#golang #testcontainers #docker

[Milan Jovanović @mjovanovictech]

Here's what my integration tests look like with Testcontainers. 👇

Each test creates a command/query and sends it using MediatR.

Under the hood, there's an actual database running in a Docker container. This is powered by Testconatiners.

[Andre Hofmeister @hovfefe]

@intellijidea @shelajev @shelajev really nice shirt 👏

[Andre Hofmeister @hovfefe]

I've put together a few slides for future Testcontainers for .NET talks. If you're interested in discussing Testcontainers, let me know. Feedback on the slides is welcome as well: https://t.co/RgVWUfhSXa.

[Andre Hofmeister @hovfefe]

@mdelapenya and mental muscles officially on vacation 🏖️

[Andre Hofmeister @hovfefe]

@Kiview @mitsuhiko @steipete @EricDocker This is basically what I do as well. I create a new campaign using my "forked" version of https://t.co/OPomFLo7ev (usually I need multiple repos), then apply the changes and push them.

[Andre Hofmeister @hovfefe]

@ErikEJ Isn't there a sidecar container that can be used for DACPACs, similar to Flyway (https://t.co/76QV0Yn4PH)?

[Andre Hofmeister @hovfefe]

Check out Testcontainers (https://t.co/2TSeSe3Dvv) and test against real dependencies with confidence.

[Andre Hofmeister @hovfefe]

I never expected such an amazing journey when I started working on Testcontainers for .NET years ago. I've met many great people and learned a lot. I'm truly grateful for all of it. I never imagined the packages would one day pass 150M+ downloads!

[Andre Hofmeister @hovfefe]

I will address this limitation in upcoming releases.

[Andre Hofmeister @hovfefe]

Docker.DotNet is now compatible with the latest Docker Engine v29 (https://t.co/BKRTkILfii). Please note that backward compatibility with earlier API versions is limited due to the project's current structure.