Spring Workshop - Spring Cloud Netflix Eureka - Lab

This repository includes the lab assignment on implementing a discovery service using Spring Cloud Netflix Eureka.

Getting Started

In this exercise, we'll extend our baseline by adding a discovery service. We'll implement the discovery service using Spring Cloud Netflix Eureka. Before we start though, we have to make sure that the baseline builds and packages correctly into Docker images that we are able to run locally.

Building source code

The source material that we're working on comprises several Maven modules. Please make sure that everything compiles successfully. You'll find the top-level pom.xml at the root folder of the lab content. Issue a

$ mvn clean package

from within the root folder. This builds all the modules; the fat JARs for every module will be located at the target folder for each and every Maven module. Building the Docker images for our services relies on these JAR files, so make sure that you build the whole solution first before building the Docker images.

Building Docker images

The source material that you're given features a docker folder. You'll find all the scripts for the assignment in that folder. To make sure that you've got all the required Docker images present on your system, we recommend that you start up the baseline scenario. This can be done by issuing

Linux / MacOS

$ cd docker
$ ./build-containers.sh
$ docker-compose up

Windows

$ cd docker
$ build-containers.bat
$ docker-compose up

This will launch a service instance of the command service and the query service, which both expose a public HTTP API that you work with. It also launches a small Kafka cluster consisting of a single broker. This is a requirement for the interoperability between the command service and the query service. Don't worry too much about that Kafka cluster - it needs to be there, but we won't work with it.

Please make sure that both services launch correctly and respond with their public API.

• The command service listens on port 8089.
• The discovery service listens on port 8090.

Both services expose an OpenAPI UI.

• Click here for opening the OpenAPI UI for the command service.
• Click here for opening the OpenAPI UI for the query service.

The API specification is minimalistic. Nevertheless, play around with the OpenAPI UI a bit to get a feel for what we'll be working on as part of the workshop.

If you have any questions or run into problems, please don't hesitate to ask for help.

Docker CLI Hints

Starting containers using docker-compose

$ docker-compose up

Stopping containers using docker-compose

$ docker-compose stop

Removing containers using docker-compose

$ docker-compose rm -f