A Minecraft-based observability client: A Quarkus extension demo

Quick start

Both the extension and the Minecraft game itself need a Minecraft server to connect to. This extension provides a Dev Service which automatically builds a modded minecraft container and starts a modded server.

Start the minecraft client

There are two ways to do this:

The best way to connect a client is to use the client in the Forge Minecraft library. This ensures compatibility with the server. Make sure you are using Java 17. To launch the client, run

cd modded-minecraft
./gradlew runClient

License note: The first time you start the Minecraft server you may have to accept the eula by changing eula=false to eula=true in the file modded-minecraft/run/eula.txt

Start a multiplayer game, and connect to localhost:25565.

Build the extension

mvn install

Start the sample application

cd sample
quarkus dev

Interact with the web app

Arrange your windows so you can see both the minecraft client and the web application. Visit http://localhost:8080. While you're interacting with the web app, you should see things happen in the minecraft world. Visiting the page will cause a mob to spawn, and an exception (like a 404) will cause an explosion.

You can see a video of the interactions, or a longer video with voiceover.

A more complete demo script is also available.

Rebuild the minecraft server container

The maven module in the modded-minecraft directory will build a local container. Alternatively, you can run

cd modded-minecraft
podman build -t minecraft-server .

Accept the eula by changing eula=false to eula=true in the file modded-minecraft/run/eula.txt.

The container build can be a bit slow the first time, be warned. If you're in a hurry, you can turn off dev services and use ./gradlew runServer instead. If you'd like to test the built container, you can run podman run -p 25565:25565 -p 8081:8081 minecraft-server.

Using the 'official' launcher and the Java edition of Minecraft

You can also use the normal Minecraft launcher, but only if the client and server versions exactly match. Using the official client will allow graphical launch. You may need to set online-mode to true on the server, and get rid of a warning.

If using the official client, which will be un-modded, you will need to configure the client to allow you to alt-tab away from the client without it pausing and bringing up a menu. Edit options.txt in your minecraft folder , and change pauseOnLostFocus to false.

You will also need to remove the custom mod functionality from the server. This will need (todo!) an environment variable added to control that.

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Not an official Minecraft product. Not approved by or associated with Mojang or Microsoft.