chaos-monkey-spring-boot-demo

Demo of Chaos Monkey for Spring Boot Using Spring Cloud Kubernetes

Building The Containers

Each project contains a Dockerfile that will create a container for the app. You can do this easily by running ./mvn clean package -Pdocker.

NOTE You should edit the parent POM file and change the value of docker.image.prefix to your own prefix.

After building the container images you will need to push them to a repository that your Kubernetes deployment has access to, for example Docker Hub.

Deploying To Kubernetes

Each project uses Dekorate in order to build a YAML file that can be used to deploy the app to Kubernetes.

To create the YAML files all you need to do is run ./mvnw clean package. The YAML files are located in /<module>/target/classes/META-INF/dekorate.

kubectl create --filename spring-cloud-k8s-demo/toys-bestseller/configmap.yml
kubectl create --filename spring-cloud-k8s-demo/toys-bestseller/target/classes/META-INF/dekorate/kubernetes.yml
kubectl create --filename spring-cloud-k8s-demo/fashion-bestseller/target/classes/META-INF/dekorate/kubernetes.yml
kubectl create --filename spring-cloud-k8s-demo/hot-deals/target/classes/META-INF/dekorate/kubernetes.yml
kubectl create --filename spring-cloud-k8s-demo/gateway/target/classes/META-INF/dekorate/kubernetes.yml

Testing The Apps

Each app is exposes a nodeport, you will need to find the nodeport for each application in your deployment. If using MiniKube you can easily open the service by running minikube service <servicename>. For example

$ minikube service gateway

Toys Bestseller

This app exposes one endpoint at /toys/bestseller which accepts a GET request and returns JSON representing the best selling toys.

In addition all actuator endpoints are exposed, this is useful for demonstrationg the Spring Cloud Kubernetes integration with ConfigMaps.

The app uses Chaos Monkey for Spring Boot to inject random latency into RestControllers. It is disabled by default but can be enabled by changing the value of the ConfigMap you created above.

If you hit /actuator/env you should see the ConfigMap in the list of PropertySources for the app. Edit the ConfigMap in Kubernetes changing chaos.monkey.enabled from false to true. Now hit /actuator/env again and you should see the property change.

Now when you hit /toys/bestseller you should randomly see the response take a bit to come back. This will be useful when demoing Hystrix via the gateway.

In addition since the Actuator endpoints are enabled it is useful to hit /actuator/health in this app to show the health endpoint integration with Kubernetes.

Fashion Bestseller

This app exposes one endpoint at /fashion/bestseller which accepts a GET request and returns JSON representing the best selling fashion items.

Hot Deals

This app exposes one endpoint at /hotdeals which accepts a GET request and returns JSON representing deals from the fashion and toys service.

Gateway

An API gateway to the toys, fashion, and hotdeals services. There are routes that point to eat /toys/**, /fashion/** and /hotdeals**. Each of these endpoints is protected by a Hystrix circuitbreaker tha when tripped returns an empty array and the response contains a header called fallback with the value of true.

In addition there is another endpoint at /startpage which aggregates the responses from all the services.

When Chaos Monkey for Spring Boot is enabled on the toys service occationally the Hystrix circuit breaker will be tripped when the latency is injected.