This is a demo project for Quarkus developers wanting to use Smallrye Stork for service discovery and instance selection. This project uses Quarkus, the Supersonic Subatomic Java Framework.

If you want to learn more about Quarkus, please visit its website: https://quarkus.io/ .

The following picture represents our system: it's a very simple application with an UI which is calling a dispatcher resource API.

Dispatcher resource is calling a Guitar hero service running remotely. The dispatcher service use the Rest Client for that and Rest Client as shown in the picture is going to delegate to Stork the service discovery and instance selection. The Guitar hero service provides 3 instances: Slash, Jimi Hendrix and Eddie Van Halen.

Slash instance returns the slash version of duke. The hendrix instance returns the Jimmy hendrix one and is slightly slower than the Slash service. Finally, the Eddie service is the fastest but with a 20% chance of failing.

We will use Stork in the Rest client when the Dispatcher service need to invoke the remote service: Stork will locate this service. This step retrieves 3 service instances, then we need to pick one, that's where the Stork load balancing capability comes into play for selecting one according to different strategies.

Slash instance returns the slash version of duke. The hendrix instance returns the Jimmy hendrix one and is slightly slower than the Slash service. Finally, the Eddie service is the fatests but with a 20% chance of failing.

We will use Stork when the Dispatcher service need to invoke the remote service: Stork will locate this service. This steps retrieves 3 service instances, then we need to pick one, thats where the Stork load balancing capability comes into play for selecting one according to different strategies.

You can run your application in dev mode that enables live coding using:

./mvnw compile quarkus:dev

NOTE: Quarkus now ships with a Dev UI, which is available in dev mode only at http://localhost:8080/q/dev/.

The application can be packaged using:

./mvnw package

It produces the quarkus-run.jar file in the target/quarkus-app/ directory. Be aware that it’s not an über-jar as the dependencies are copied into the target/quarkus-app/lib/ directory.

The application is now runnable using java -jar target/quarkus-app/quarkus-run.jar.

If you want to build an über-jar, execute the following command:

./mvnw package -Dquarkus.package.type=uber-jar

The application, packaged as an über-jar, is now runnable using java -jar target/*-runner.jar.

You can create a native executable using:

./mvnw package -Pnative

Or, if you don't have GraalVM installed, you can run the native executable build in a container using:

./mvnw package -Pnative -Dquarkus.native.container-build=true

You can then execute your native executable with: ./target/stork-guitar-hero-1.0.0-SNAPSHOT-runner

If you want to learn more about building native executables, please consult https://quarkus.io/guides/maven-tooling.

• RESTEasy Reactive (guide): Reactive implementation of JAX-RS with additional features. This extension is not compatible with the quarkus-resteasy extension, or any of the extensions that depend on it.

Easily start your Reactive RESTful Web Services

Related guide section...

https://developer.hashicorp.com/consul/tutorials/day-0/docker-container-agents#docker-container-agents

Set up Consul in Docker

docker pull hashicorp/consul
docker images -f 'reference=hashicorp/consul'
docker run -d -p 8500:8500 -p 8600:8600/udp --name=badger hashicorp/consul agent -server -ui -node=server-1 -bootstrap-expect=1 -client=0.0.0.0
docker exec badger consul members
docker run --name=fox hashicorp/consul agent -node=client-1 -retry-join=172.17.0.3
docker exec fox /bin/sh -c "echo '{\"service\": {\"name\": \"slash\", \"tags\": [\"guns-n-roses\"], \"port\": 9000}}' >> /consul/config/slash.json"
docker exec fox /bin/sh -c "echo '{\"service\": {\"name\": \"hendrix\", \"tags\": [\"jimi\"], \"port\": 9001}}' >> /consul/config/hendrix.json"
docker exec fox /bin/sh -c "echo '{\"service\": {\"name\": \"eddie\", \"tags\": [\"van-halen\"], \"port\": 9002}}' >> /consul/config/eddie.json"\n
docker exec fox consul reload
curl -X PUT -d '{"ID": "slash", "Name": "guitar-hero-service", "Address": "localhost", "Port": 9000, "Tags": ["guns-n-roses","slash"]}' http://127.0.0.1:8500/v1/agent/service/register
curl -X PUT -d '{"ID": "hendrix", "Name": "guitar-hero-service", "Address": "localhost", "Port": 9001, "Tags": ["legend","Woodstock"] }' http://127.0.0.1:8500/v1/agent/service/register
curl -X PUT -d '{"ID": "eddie", "Name": "guitar-hero-service", "Address": "localhost", "Port": 9002, "Tags": ["van-halen","Frankenstrat"]}' http://127.0.0.1:8500/v1/agent/service/register\n

Register services:

docker exec fox /bin/sh -c "echo '{\"service\": {\"name\": \"slash\", \"tags\": [\"guns-n-roses\"], \"port\": 9000}}' >> /consul/config/slash.json"
docker exec fox /bin/sh -c "echo '{\"service\": {\"name\": \"hendrix\", \"tags\": [\"jimi\"], \"port\": 9001}}' >> /consul/config/hendrix.json"
docker exec fox /bin/sh -c "echo '{\"service\": {\"name\": \"eddie\", \"tags\": [\"van-halen\"], \"port\": 9002}}' >> /consul/config/eddie.json"
docker exec fox consul reload

curl -X PUT -d '{"ID": "slash", "Name": "guitar-hero-service", "Address": "localhost", "Port": 9000, "Tags": ["guns-n-roses","slash"]}' http://127.0.0.1:8500/v1/agent/service/register
curl -X PUT -d '{"ID": "hendrix", "Name": "guitar-hero-service", "Address": "localhost", "Port": 9001, "Tags": ["legend","Woodstock"] }' http://127.0.0.1:8500/v1/agent/service/register
curl -X PUT -d '{"ID": "eddie", "Name": "guitar-hero-service", "Address": "localhost", "Port": 9002, "Tags": ["van-halen","Frankenstrat"]}' http://127.0.0.1:8500/v1/agent/service/register

Deleting a service instance

curl -X PUT http://127.0.0.1:8500/v1/agent/service/deregister/slash