On the fabric8<\/a> project we\u2019ve been focused on making it easy for developers to create, build, deploy and manage microservices on top of Kubernetes for some time.<\/p>\n Up to now we\u2019ve mostly focused on the end to end lifecycle of creating new microservices, then changing code through continuous delivery then having continuous improvement. Lately we\u2019ve been focused more on the pre-git-push<\/i> phase. Where you\u2019re hacking code on your laptop and trying things out before you want to commit and push into your git repository.<\/p>\n Lots of Java developers are used to using application servers, creating deployment units (jars\/wars), deploying them and running them in app servers using Maven. Then they can use Maven from the command line or easily inside their IDE to do most of the work.<\/p>\n So we figured, why not make Kubernetes look and feel like an application server to a Java developer? So you build and deploy your application from maven like you would with other maven plugins like spring-boot, tomcat, jetty, wildfly, karaf et al. Then you can get started quickly by just treating Kubernetes as a kind of application server.<\/p>\n Kubernetes is actually way more awesome than an application server; its more like an application cloud<\/i> as:<\/p>\n Do you have an existing maven project for your Java app? Maybe its a Spring Boot or WildFly Swarm app; or a flat classpath, fat jar? If you don\u2019t have a maven app to hand, visit start.spring.io<\/a> and create one.<\/p>\n To enable fabric8 on your project just type this fabric8:setup<\/a> command which adds the fabric8-maven-plugin<\/a> to your pom.xml<\/i> like this example<\/a>.<\/p>\n Note that all the fabric8 quickstarts<\/a> already have the fabric8 maven plugin enabled so you don\u2019t need to do the above!<\/p>\n Now that we have enabled the fabric8 maven plugin for our project we can have some fun!<\/p>\n To develop on kubernetes you will need a kubernetes cluster; just like you need an instance of an application server to deploy your app. If someone in your organisation has provided you with a kubernetes cluster then feel free to use that; you just need to connect to it via the kubectl<\/a> too.<\/p>\n However if you don\u2019t have any kubernetes clusters to hand its very easy to spin up your own local cluster. Using a local kubernetes cluster is really handy for development; it lets you build your app and run it locally before you do a git commit and trigger the CI \/ CD pipeline.<\/p>\n Before you start please make sure you have the <\/b>prerequisites installed<\/a> for your platform (basically a recent Apache Maven distro and have a working hypervisor for your platform like xhyve, hyper-v or kvm).<\/p>\n Now with the fabric8-maven-plugin you just use the goal fabric8:cluster-start<\/a> to spin up a local cluster:<\/p>\n Wait a few minutes for some stuff to download and then you\u2019ve now got a local installation of a Kubernetes cluster running on your machine! No installation of Docker, VirtualBox or Vagrant is required!<\/p>\n Under the covers this downloaded gofabric8<\/a> and ran gofabric8<\/i> start which then downloaded minikube<\/a> and kubectl<\/a> binaries and installs them into ~\/.fabric8\/bin<\/i><\/p>\n Want to use OpenShift instead of Kubernetes? Use this command<\/a> instead:<\/p>\n You can now use the kubectl<\/a> command line to get pods and whatnot:<\/p>\n When you\u2019re done and want to stop the kubernetes cluster just use fabric8:cluster-stop<\/a><\/p>\n you can restart it again at any time via fabric8:cluster-start<\/a><\/p>\n The simplest way to run your app is viafabric8:run<\/a><\/p>\n This will build your app (compile code, run tests, generate the jar and package it up into an immutable docker image), generate the kubernetes manifest and deploy it then tail the log output so you can see how your app behaves. If you hit Ctrl-C<\/i> it then terminates the app.<\/p>\n So that the fabric8:run<\/i> goal works kinda like other run goals in other maven projects like spring-boot<\/i>, tomcat<\/i>, jetty<\/i>, karaf<\/i> and wildfly<\/i>.<\/p>\n Deploying your app is a little like running fabric8:run<\/a> in the background.<\/p>\n To deploy your app into kubernetes you use the fabric8:deploy<\/a> goal<\/p>\n This will build your java code and run your unit tests, generate the docker image, create the kubernetes manifest and deploy them into kubernetes.<\/p>\n To remove our app from kubernetes just use the fabric8:undeploy<\/a> goal<\/p>\n Once you\u2019ve deployed your app you probably want to check its logs. So you can type:<\/p>\n then hit Ctrl-C<\/i> to terminate tailing the log.<\/p>\n If you don\u2019t want to keep tailing the log and just want to see the current log output try this:<\/p>\n If you have deployed your app you sometimes want to stop it running so that you can later on start it again. e.g. since its using up resources on your laptop or its invoking some other microservice that you wish to take offline.<\/p>\n To stop your application just use the fabric8:stop<\/a> and fabric8:start<\/a> goal:<\/p>\n All the fabric8:start<\/a> and fabric8:stop<\/a> goals do is to scale your application on Kubernetes\u200a\u2014\u200aas in set the number of expected replicas\u200a\u2014\u200athe number of running processes of your app.<\/p>\n You can also use fabric8:start<\/a> to scale up your app to more than one pod if you wish<\/p>\n![\"fabric](\"http:\/\/www.eclipse.org\/community\/eclipse_newsletter\/2017\/january\/images\/fabric8.png\")
<\/a><\/p>\n\n
Setup your maven project<\/h2>\n
mvn io.fabric8:fabric8-maven-plugin:3.2.8:setup<\/pre>\n
Starting and stopping a local kubernetes cluster<\/h2>\n
mvn fabric8:cluster-start<\/pre>\n
mvn fabric8:cluster-start -Dfabric8.cluster.kind=openshift<\/pre>\n
kubectl get pod<\/pre>\n
mvn fabric8:cluster-stop<\/pre>\n
Running your app<\/h2>\n
mvn fabric8:run<\/pre>\n
Deploy or undeploy your app<\/h2>\n
mvn fabric8:deploy<\/pre>\n
mvn fabric8:undeploy<\/pre>\n
Viewing logs<\/h2>\n
mvn fabric8:log<\/pre>\n
mvn fabric8:log -Dfabric8.log.follow=false<\/pre>\n
Start and stop<\/h2>\n
mvn fabric8:stop\n\u2026\nmvn fabric8:start<\/pre>\n
mvn fabric8:start -Dfabric8.replicas=2<\/pre>\n
![\"debug](\"http:\/\/www.eclipse.org\/community\/eclipse_newsletter\/2017\/january\/images\/debug.png\")
<\/p>\n![\"debug](\"http:\/\/www.eclipse.org\/community\/eclipse_newsletter\/2017\/january\/images\/debugtitle.png\")
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