Minecraft as an observability client: A Quarkus extension demo

Quick start

Start the minecraft server

cd modded-minecraft
./gradlew runServer

INFO: First time you start the Mincraft server you will have to accept the eula by changing eula=false to eula=true in the file modded-minecraft/run/eula.txt

Start the minecraft client

There are two ways to do this:

• Java edition of Minecraft. This has a nice desktop icon, but it means the code needs to be upgraded every time a new client is released. The libraries do not have much backwards compatibility between releases.
• The client in the Forge Minecraft library. This ensures compatibility with the server. To launch it, run

cd modded-minecraft
./gradlew runClient

In either case, start a multiplayer game, and connect to localhost:25565.

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.

pauseOnLostFocus:false

Build the extension

cd extension/minecrafter
mvn install

Start the sample application

cd quarkus-todo-app
quarkus dev

(If you do mvn install, with podman it should be TESTCONTAINERS_RYUK_DISABLED="true" mvn install.)

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.