Circuit Breaker Spring Boot Example

Table of Contents

• Circuit Breaker Spring Boot Example
  • Introduction
  • Deploying application on OpenShift using Dekorate
  • Deploying application on OpenShift using Helm
  • Deploying application on Kubernetes using Helm
  • Running Tests on OpenShift using Dekorate
  • Running Tests on OpenShift using S2i from Source
  • Running Tests on OpenShift using Helm
  • Running Tests on Kubernetes with Helm
  • Test the service
    • Maven Test
    • Manual Test

Introduction

https://appdev.openshift.io/docs/spring-boot-runtime.html#mission-circuit-breaker-spring-boot

Deploying application on OpenShift using Dekorate

• For the Greeting Service:

./mvnw clean verify -pl greeting-service -Popenshift -Ddekorate.deploy=true

• For the Name Service:

./mvnw clean verify -pl name-service -Popenshift -Ddekorate.deploy=true

Deploying application on OpenShift using Helm

First, make sure you have installed the Helm command line and connected/logged to a kubernetes cluster.

Then, you need to install the example by doing:

helm install circuit-breaker ./helm --set name-service.route.expose=true --set name-service.s2i.source.repo=https://github.com/snowdrop/circuit-breaker-example --set name-service.s2i.source.ref=<branch-to-use> --set greeting-service.route.expose=true --set greeting-service.s2i.source.repo=https://github.com/snowdrop/circuit-breaker-example --set greeting-service.s2i.source.ref=<branch-to-use>

note: Replace <branch-to-use> with one branch from https://github.com/snowdrop/circuit-breaker-example/branches/all.

And to uninstall the chart, execute:

helm uninstall circuit-breaker

Deploying application on Kubernetes using Helm

Requirements:

• Have installed the Helm command line
• Have connected/logged to a kubernetes cluster

You need to install the example by doing:

helm install circuit-breaker ./helm -n <k8s namespace> --set name-service.ingress.host=<your k8s domain> --set greeting-service.ingress.host=<your k8s domain>

And to uninstall the chart, execute:

helm uninstall circuit-breaker

Running Tests on OpenShift using Dekorate

./run_tests_with_dekorate_in_ocp.sh

Running Tests on OpenShift using S2i from Source

./run_tests_with_s2i.sh

This script can take 2 parameters referring to the repository and the branch to use to source the images from.

./run_tests_with_s2i.sh "https://github.com/snowdrop/circuit-breaker-example" branch-to-test

Running Tests on OpenShift using Helm

./run_tests_with_helm_in_ocp.sh

This script can take 2 parameters referring to the repository and the branch to use to source the images from.

./run_tests_with_helm_in_ocp.sh "https://github.com/snowdrop/circuit-breaker-example" branch-to-test

Running Tests on Kubernetes using Helm

First, you need to create the k8s namespace:

kubectl create namespace <the k8s namespace>

Then, run the tests by specifying the container registry and the kubernetes namespace:

./run_tests_with_helm_in_k8s.sh <your container registry: for example "quay.io/user"> <the k8s namespace>

For example:

./run_tests_with_helm_in_k8s.sh "quay.io/user" "myNamespace"

Test the service

Maven Test

This service can be tested using the following Maven task.

$ mvn clean verify

Manual Test

$ oc get route
NAME                                   HOST/PORT                                                                                                                                      PATH   SERVICES                               PORT   TERMINATION   WILDCARD
greeting                               greeting-circuit-breaker.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance                                      greeting                               8080                 None
spring-boot-circuit-breaker-greeting   spring-boot-circuit-breaker-greeting-circuit-breaker.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance          spring-boot-circuit-breaker-greeting   8080                 None
spring-boot-circuit-breaker-name       spring-boot-circuit-breaker-name-circuit-breaker.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance              spring-boot-circuit-breaker-name       8080                 None

Check the name-service state.

$ curl http://spring-boot-circuit-breaker-name-default.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/info
{"state":"ok"}

Call the name-service name service on OK state.

$ curl http://spring-boot-circuit-breaker-name-default.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/name
World

Set the service status to FAIL using GET.

$ curl "http://spring-boot-circuit-breaker-name-default.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/state?state=fail"
{"state":"fail"}

Call the name-service name service on fail state.

$ curl -v http://spring-boot-circuit-breaker-name-default.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/name
...
< HTTP/1.1 500
...
Name service down

Set the service status to OK using PUT.

$ curl -X PUT -H "Content-Type: application/json" --data '{"state":"ok"}' "http://spring-boot-circuit-breaker-name-default.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/state"
{"state":"ok"}

Call the greeting service having the name service OK.

$ curl -X PUT -H "Content-Type: application/json" --data '{"state":"ok"}' "http://greeting-circuit-breaker.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/state"
{"content":"Hello, World!"}

Set the service status to FAIL using PUT.

$ curl -X PUT -H "Content-Type: application/json" --data '{"state":"fail"}' "http://spring-boot-circuit-breaker-name-default.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/state"
{"state":"fail"}

Call the greeting service having the name service OK.

$ curl -X PUT -H "Content-Type: application/json" --data '{"state":"ok"}' "http://greeting-circuit-breaker.snowdrop-ocp-470-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx-0000.my.openshift.instance/api/state"
{"content":"Hello, Fallback!"}