1e71319f9f
* updating discovery and config modules, removing netflix modules to start simple * hacking some jackson dependencies as they were not working * update Discovery AutoConfiguration, still messy, more work needed here * getting configuration working with the service registry * removing profiles check document matcher that doesn't exist anymore * fixing configMaps example * improving readmes and removing arquillian due it requires undertow * re adding all netflix modules * re adding commented example modules * fixing minor naming issues and adding commented out modules
71 lines
2.5 KiB
Markdown
71 lines
2.5 KiB
Markdown
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# Setting up the Environment
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To play with these examples, you can install locally Kubernetes & Docker using `[Minikube](https://kubernetes.io/docs/getting-started-guides/minikube/)` within a Virtual Machine
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managed by a hypervisor (Xhyve, Virtualbox or KVM) if your machine is not a native Unix operating system.
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When the minikube is installed on your machine, you can start kubernetes using this command:
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```
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minikube start
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```
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You also probably want to configure your docker client to point the minikube docker deamon with:
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```
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eval $(minikube docker-env)
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```
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This will make sure that the docker images that you build are available to the minikube environment.
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## Kubernetes Reload Example
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This example demonstrate how to use the reload feature to change the configuration of a spring-boot application at runtime.
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The application consists of a timed bean that periodically prints a message to the console.
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The message can be changed using a config map.
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### Running the example
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Once you have your environment set up, you can deploy the application using the fabric8 maven plugin:
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```
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mvn clean install fabric8:build fabric8:deploy -Pintegration
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```
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**Note**: Unfortuntaly, when you deploy using the fabric8 plugin, the readyness and liveness probes fail to point to the right actuator URL due a lack of support for spring boot.
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This push you to edit the generated deployment inside kubernetes and change these probes which points to "path": "/health" to "path": "/actuator/health".
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This will make your deployment go green. This issue is already reported into the fabric8 community: https://github.com/fabric8io/fabric8-maven-plugin/issues/1178
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### Changing the configuration
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Create a yaml file with the following contents:
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```yml
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apiVersion: v1
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kind: ConfigMap
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metadata:
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name: reload-example
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data:
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application.properties: |-
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bean.message=Hello World!
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another.property=value
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```
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A sample config map is provided with this example in the *config-map.yml* file.
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To deploy the config map, just run the following command on Kubernetes:
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```
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kubectl create -f config-map.yml
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```
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As soon as the config map is deployed, the output of the application changes accordingly.
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The config map can be now edited with the following command:
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```
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kubectl edit configmap reload-example
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```
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Changes are applied immediately when using the *event* reload mode.
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The name of the config map (*"reload-example"*) matches the name of the application as declared in the *application.properties* file.
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