25 years ago, Java went into the programming masses to eventually become one of the pillars around which application stacks are built. Today, however, many people and organizations that have been loyal to Java for many years are busy moving or thinking of moving to the Java platform. or its derivatives such as or .
Alas, Kubernetes has a steep learning curve and introduces another operational layer into the Java development process that is familiar to Java programmers. Today we will show you how to use to simplify these additional operations associated with Kubernetes and containers, as well as provide a painless migration to the cloud while maintaining the familiar Java ecosystem. Moreover, we will show how to deploy Java applications on the OpenShift platform using the OpenShift Maven plugin.
Traditional Java development process
Traditional development process (Figure 1) implies that a developer writes code, then creates deployment units as JAR or WAR files, and then deploys and runs those files on a web or application server. This is mostly done using Maven from the command line, or using an IDE like IntelliJ or Eclipse to code and package applications. Developers are accustomed to making changes to the code and testing everything thoroughly before committing the code and submitting it to source control.
Rice. 1. Traditional Java development process.
Java development process for the cloud
With the transition to cloud applications, Kubernetes and . Therefore, now the developer needs to package Java applications in and create Kubernetes manifests that describe these images. These manifests are then applied to the production server running Kubernetes. In turn, Kubernetes takes these images from the registry and deploys applications according to the configurations that we have written in the manifests, which are usually YAML files.
The metamorphosis of the traditional Java development process in moving to the cloud is shown in Fig. 2.
Rice. 2. Java development process for the cloud.
Eclipse JKube
The transition to Kubernetes adds another operational layer to the development process, and many developers are unnerved by this, because they want to focus on their core job - application logic - and not how to deploy them. And here comes into play , which allows developers to use their libraries and plugins ( with or ) to effortlessly perform operations related to containers and Kubernetes, following the scheme in Fig. 2.
In the rest of this article, we'll show you how to simplify the Java development process in a Kubernetes environment using Eclipse JKube with the Kubernetes Maven Plugin.
Development process for the cloud using Eclipse JKube
Let's consider a slightly modified cloud Java development flow from Figure 2 by injecting Eclipse JKube and Kubernetes Maven Plugin into it, as shown in Figure 3. XNUMX.
Rice. 3. Java development process for the cloud using Eclipse JKube.
As we can see, here all operations for interacting with Kubernetes and containers (highlighted in red in the diagram) are replaced by default Eclipse JKube goals, which are listed in Table. 1.
Tab. 1. Eclipse JKube default tasks.
Task
Stage
Description
PRE_INTEGRATION_TEST
Building docker images
INSTALL
Pushing Docker Images to the Registry
PROCESS_RESOURCES
Generating K8s Manifests
COMPILE
Applying Generated Manifests to K8s
UNDEPLOY
Deleting K8s resources that have been deployed with k8s:apply and k8s:deploy
Note: If you do not want tasks to use these hard defaults (opinionated defaults), then you can manually configure Eclipse JKube for yourself, since it supports configuration via ΠΈ .
Now let's look at examples of using Eclipse JKube and Kubernetes Maven Plugin when working with applications.
Deploy Java Application to Kubernetes with Eclipse JKube
In this example, we will deploy a simple Java application on a cluster using Eclipse JKube. Using the Kubernetes Maven Plugin, we can set deployment options without writing any configuration.
As an example application, we use , which produces JSON-output at the /random endpoint:
~/work/repos/eclipse-jkube-demo-project : $ curl localhost:8080/random | jq .
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 45 0 45 0 0 818 0 --:--:-- --:--:-- --:--:-- 818
{
"id": "e80a4d10-c79b-4b9a-aaac-7c286cb37f3c"
}
Step 1Download the Kubernetes Maven Plugin
Kubernetes Maven Plugin is in the repository . To use Eclipse JKube, add the Kubernetes Maven Plugin to your pom.xml as a dependency:
<plugin>
<groupId>org.eclipse.jkube</groupId>
<artifactId>kubernetes-maven-plugin</artifactId>
<version>${jkube.version}</version>
</plugin>
If OpenShift is used instead of pure Kubernetes, then pom.xml is modified as follows:
<plugin>
<groupId>org.eclipse.jkube</groupId>
<artifactId>openshift-maven-plugin</artifactId>
<version>${jkube.version}</version>
</plugin>
Step 2. Building a docker image
The application JAR file can be built with the mvn package command, and then the mvn k8s:build goal can be used to build the docker image of this application. Note that we have overridden the default image name with this property:
<jkube.generator.name>docker.io/rohankanojia/random-generator:${project.version}</jkube.generator.name>
Before building the image, you need to make sure that the docker daemon is correctly exposed. This can be done with the following command:
$ eval $(minikube docker-env)
Then we enter the mvn k8s:build command, and this is what we will see on the screen when we build the docker image using the Eclipse JKube build task:
~/work/repos/eclipse-jkube-demo-project : $ mvn k8s:build
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< meetup:random-generator >-----------------------
[INFO] Building random-generator 0.0.1
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- kubernetes-maven-plugin:1.0.0-rc-1:build (default-cli) @ random-generator ---
[INFO] k8s: Running in Kubernetes mode
[INFO] k8s: Building Docker image in Kubernetes mode
[INFO] k8s: Running generator spring-boot
[INFO] k8s: spring-boot: Using Docker image quay.io/jkube/jkube-java-binary-s2i:0.0.7 as base / builder
[INFO] k8s: [docker.io/rohankanojia/random-generator:0.0.1] "spring-boot": Created docker-build.tar in 251 milliseconds
[INFO] k8s: [docker.io/rohankanojia/random-generator:0.0.1] "spring-boot": Built image sha256:a20e5
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 5.053 s
[INFO] Finished at: 2020-08-10T11:28:23+05:30
[INFO] ------------------------------------------------------------------------
~/work/repos/eclipse-jkube-demo-project : $
Step 3. Pushing the Image to the Docker Registry
After we have built a docker image with a configured push registry (in our case, docker.io), we can push this image to the registry. Here is what will be displayed after we ask Eclipse JKube to perform the mvn k8s:push push task:
~/work/repos/eclipse-jkube-demo-project : $ mvn k8s:push
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< meetup:random-generator >-----------------------
[INFO] Building random-generator 0.0.1
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- kubernetes-maven-plugin:1.0.0-rc-1:push (default-cli) @ random-generator ---
[INFO] k8s: Running in Kubernetes mode
[INFO] k8s: Building Docker image in Kubernetes mode
[INFO] k8s: Running generator spring-boot
[INFO] k8s: spring-boot: Using Docker image quay.io/jkube/jkube-java-binary-s2i:0.0.7 as base / builder
[INFO] k8s: The push refers to repository [docker.io/rohankanojia/random-generator]
5dcd9556710f: Layer already exists
b7139ad07aa8: Layer already exists
b6f081e4b2b6: Layer already exists
d8e1f35641ac: Layer already exists
[INFO] k8s: 0.0.1: digest: sha256:9f9eda2a13b8cab1d2c9e474248500145fc09e2922fe3735692f9bda4c76002d size: 1162
[INFO] k8s: Pushed docker.io/rohankanojia/random-generator:0.0.1 in 7 seconds
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 11.222 s
[INFO] Finished at: 2020-08-10T11:35:37+05:30
[INFO] ------------------------------------------------------------------------
~/work/repos/eclipse-jkube-demo-project : $
After sending the image, you need to check that it got into the registry. In our case, we just see it in Docker Hub, as shown in Fig. 4.
Rice. 4. The image submitted to the registry appeared in Docker Hub.
Step 4: Generating Kubernetes Resource Manifests for the Application
So, we have assembled the application image, now we need to write Kubernetes manifests. To do this, Eclipse JKube has a task that generates hard resource manifests based on the underlying Java framework (, , Vert.x or some other). It is also possible to customize the manifest by using an XML config file and putting the raw fragments (fragments of the required resource manifest) in the application's src/main/jkube folder. In this case, your configuration will be uploaded to the generated manifests.
In our example, we leave everything as it is, and therefore Eclipse JKube generates a manifest for the default deployment and for a service with type ClusterIP. And only then we modify the service manifest to change the service type to NodePort. You can override the default behavior with the following property:
<jkube.enricher.jkube-service.type>NodePort</jkube.enricher.jkube-service.type>
This is what the screen output looks like after we ask Eclipse JKube to run the mvn k8s:resource resource task.
~/work/repos/eclipse-jkube-demo-project : $ mvn k8s:resource
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< meetup:random-generator >-----------------------
[INFO] Building random-generator 0.0.1
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- kubernetes-maven-plugin:1.0.0-rc-1:resource (default-cli) @ random-generator ---
[INFO] k8s: Running generator spring-boot
[INFO] k8s: spring-boot: Using Docker image quay.io/jkube/jkube-java-binary-s2i:0.0.7 as base / builder
[INFO] k8s: jkube-controller: Adding a default Deployment
[INFO] k8s: jkube-service: Adding a default service 'random-generator' with ports [8080]
[INFO] k8s: jkube-healthcheck-spring-boot: Adding readiness probe on port 8080, path='/actuator/health', scheme='HTTP', with initial delay 10 seconds
[INFO] k8s: jkube-healthcheck-spring-boot: Adding liveness probe on port 8080, path='/actuator/health', scheme='HTTP', with initial delay 180 seconds
[INFO] k8s: jkube-revision-history: Adding revision history limit to 2
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3.344 s
[INFO] Finished at: 2020-08-10T11:38:11+05:30
[INFO] ------------------------------------------------------------------------
~/work/repos/eclipse-jkube-demo-project : $ ls target/classes/META-INF/jkube/kubernetes
random-generator-deployment.yml random-generator-service.yml
~/work/repos/eclipse-jkube-demo-project : $ cat target/classes/META-INF/jkube/kubernetes/random-generator-deployment.yml | head -n10
---
apiVersion: apps/v1
kind: Deployment
metadata:
annotations:
jkube.io/git-url: [email protected]:rohanKanojia/eclipse-jkube-demo-project.git
jkube.io/git-commit: 1ef9ef2ef7a6fcbf8eb64c293f26f9c42d026512
jkube.io/git-branch: master
jkube.io/scm-url: https://github.com/spring-projects/spring-boot/spring-boot-starter-parent/random-generator
jkube.io/scm-tag: HEAD
~/work/repos/eclipse-jkube-demo-project : $
Step 5: Deploying the Application to a Kubernetes Cluster
So, we are all set to deploy the application: we generated its image and then automatically generated the resource manifests. Now all that's left is to apply all this to the Kubernetes cluster. To deploy the application, you can, of course, use the kubectl apply -f command, but the plugin can do this for us. Here is what will be on the screen after we ask Eclipse JKube to execute the mvn k8s:apply apply task:
~/work/repos/eclipse-jkube-demo-project : $ mvn k8s:apply
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< meetup:random-generator >-----------------------
[INFO] Building random-generator 0.0.1
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- kubernetes-maven-plugin:1.0.0-rc-1:apply (default-cli) @ random-generator ---
[INFO] k8s: Using Kubernetes at https://192.168.39.145:8443/ in namespace default with manifest /home/rohaan/work/repos/eclipse-jkube-demo-project/target/classes/META-INF/jkube/kubernetes.yml
[INFO] k8s: Using namespace: default
[INFO] k8s: Creating a Service from kubernetes.yml namespace default name random-generator
[INFO] k8s: Created Service: target/jkube/applyJson/default/service-random-generator.json
[INFO] k8s: Creating a Deployment from kubernetes.yml namespace default name random-generator
[INFO] k8s: Created Deployment: target/jkube/applyJson/default/deployment-random-generator.json
[INFO] k8s: HINT: Use the command `kubectl get pods -w` to watch your pods start up
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 7.306 s
[INFO] Finished at: 2020-08-10T11:40:57+05:30
[INFO] ------------------------------------------------------------------------
~/work/repos/eclipse-jkube-demo-project : $ kubectl get pods -w
NAME READY STATUS RESTARTS AGE
random-generator-58b7847d7f-9m9df 0/1 Running 0 7s
random-generator-58b7847d7f-9m9df 1/1 Running 0 17s
^C~/work/repos/eclipse-jkube-demo-project : $ kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
io-openliberty-sample-getting-started NodePort 10.110.4.104 <none> 9080:30570/TCP 44h
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 18d
random-generator NodePort 10.97.172.147 <none> 8080:32186/TCP 22s
~/work/repos/eclipse-jkube-demo-project : $ curl `minikube ip`:32186/random | jq .
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 45 0 45 0 0 1800 0 --:--:-- --:--:-- --:--:-- 1875
{
"id": "42e5571f-a20f-44b3-8184-370356581d10"
}
Step 6: Undeploy Applications from the Kubernetes Cluster
For this, the undeploy task is used, which simply removes all the resources that were applied in the previous step, that is, when the apply task was executed. Here is what we will see on the screen after we ask Eclipse JKube to execute the mvn k8s:undeploy undeploy task:
~/work/repos/eclipse-jkube-demo-project : $ kubectl get all
NAME READY STATUS RESTARTS AGE
pod/random-generator-58b7847d7f-9m9df 1/1 Running 0 5m21s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 18d
service/random-generator NodePort 10.97.172.147 <none> 8080:32186/TCP 5m21s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/random-generator 1/1 1 1 5m21s
NAME DESIRED CURRENT READY AGE
replicaset.apps/random-generator-58b7847d7f 1 1 1 5m21s
~/work/repos/eclipse-jkube-demo-project : $ mvn k8s:undeploy
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< meetup:random-generator >-----------------------
[INFO] Building random-generator 0.0.1
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- kubernetes-maven-plugin:1.0.0-rc-1:undeploy (default-cli) @ random-generator ---
[INFO] k8s: Using Kubernetes at https://192.168.39.145:8443/ in namespace default with manifest /home/rohaan/work/repos/eclipse-jkube-demo-project/target/classes/META-INF/jkube/kubernetes.yml
[INFO] k8s: Using namespace: default
[INFO] k8s: Deleting resource Deployment default/random-generator
[INFO] k8s: Deleting resource Service default/random-generator
[INFO] k8s: HINT: Use the command `kubectl get pods -w` to watch your pods start up
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3.412 s
[INFO] Finished at: 2020-08-10T11:46:22+05:30
[INFO] ------------------------------------------------------------------------
~/work/repos/eclipse-jkube-demo-project : $ kubectl get pods -w
^C~/work/repos/eclipse-jkube-demo-project : $ kubectl get all
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 18d
~/work/repos/eclipse-jkube-demo-project : $
What else can be done with Eclipse JKube
So, we have considered the main goals of Eclipse JKube and Kubernetes Maven Plugin, which facilitate the development of Java applications for the Kubernetes platform. If you do not want to constantly enter these tasks from the keyboard, you can write them in the plugin configuration, for example, like this:
<plugin>
<groupId>org.eclipse.jkube</groupId>
<artifactId>kubernetes-maven-plugin</artifactId>
<version>${project.version}</version>
<executions>
<execution>
<goals>
<goal>build</goal>
<goal>resource</goal>
<goal>apply</goal>
</goals>
</execution>
</executions>
</plugin>
I must say that in this article we have not considered all the goal tasks that are in Eclipse JKube and Kubernetes Maven Plugin, so we provide in Table 2 a list of additional tasks that may also be useful to you.
Tab. 2. Additional goals for Eclipse JKube.
Task
Stage
Description
VALIDATED
Getting logs from an application running on Kubernetes.
PACKAGE
Open a debug port to debug an application running on Kubernetes directly from the IDE.
INSTALL
Forking the Install task and applying the generated manifests to the Kubernetes cluster is exactly the same as with the apply task.
PACKAGE
Automatically hot deploy an application by keeping track of its namespace.
Deploying Java Applications on Red Hat OpenShift Using the OpenShift Maven Plugin
To deploy the application from our example on the Red Hat OpenShift platform, we use the plugin . The only difference will be that the task prefix will change from k8s to oc. By default, the Kubernetes Maven plugin does -assemblies, and the OpenShift Maven plugin -assemblies . We don't make any changes to our project other than removing the jkube.generator.name property, as it is not required when pushing to the registry (during the build phase, OpenShift hosts the image in its internal registry). And this is what will appear on the screen when we run our example, in which, by the way, we are executing goal tasks not one at a time, but all at once:
~/work/repos/eclipse-jkube-demo-project : $ mvn oc:build oc:resource oc:apply
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< meetup:random-generator >-----------------------
[INFO] Building random-generator 0.0.1
[INFO] --------------------------------[ jar ]---------------------------------
[INFO]
[INFO] --- openshift-maven-plugin:1.0.0-rc-1:build (default-cli) @ random-generator ---
[INFO] oc: Using OpenShift build with strategy S2I
[INFO] oc: Running in OpenShift mode
[INFO] oc: Running generator spring-boot
[INFO] oc: spring-boot: Using Docker image quay.io/jkube/jkube-java-binary-s2i:0.0.7 as base / builder
[INFO] oc: [random-generator:0.0.1] "spring-boot": Created docker source tar /home/rohaan/work/repos/eclipse-jkube-demo-project/target/docker/random-generator/0.0.1/tmp/docker-build.tar
[INFO] oc: Adding to Secret pullsecret-jkube
[INFO] oc: Using Secret pullsecret-jkube
[INFO] oc: Creating BuildServiceConfig random-generator-s2i for Source build
[INFO] oc: Creating ImageStream random-generator
[INFO] oc: Starting Build random-generator-s2i
[INFO] oc: Waiting for build random-generator-s2i-1 to complete...
[INFO] oc: Caching blobs under "/var/cache/blobs".
[INFO] oc: Getting image source signatures
[INFO] oc: Copying blob sha256:cf0f3ebe9f536c782ab3835049cfbd9a663761ded9370791ef6ea3965c823aad
[INFO] oc: Copying blob sha256:57de4da701b511cba33bbdc424757f7f3b408bea741ca714ace265da9b59191a
[INFO] oc: Copying blob sha256:f320f94d91a064281f5127d5f49954b481062c7d56cce3b09910e471cf849050
[INFO] oc: Copying config sha256:52d6788fcfdd39595264d34a3959464a5dabc1d4ef0ae188802b20fc2d6a857b
[INFO] oc: Writing manifest to image destination
[INFO] oc: Storing signatures
[INFO] oc: Generating dockerfile with builder image quay.io/jkube/jkube-java-binary-s2i:0.0.7
[INFO] oc: STEP 1: FROM quay.io/jkube/jkube-java-binary-s2i:0.0.7
[INFO] oc: STEP 2: LABEL "io.openshift.build.source-location"="/tmp/build/inputs" "io.openshift.build.image"="quay.io/jkube/jkube-java-binary-s2i:0.0.7"
[INFO] oc: STEP 3: ENV JAVA_APP_DIR="/deployments" OPENSHIFT_BUILD_NAME="random-generator-s2i-1" OPENSHIFT_BUILD_NAMESPACE="default"
[INFO] oc: STEP 4: USER root
[INFO] oc: STEP 5: COPY upload/src /tmp/src
[INFO] oc: STEP 6: RUN chown -R 1000:0 /tmp/src
[INFO] oc: STEP 7: USER 1000
[INFO] oc: STEP 8: RUN /usr/local/s2i/assemble
[INFO] oc: INFO S2I source build with plain binaries detected
[INFO] oc: INFO S2I binary build from fabric8-maven-plugin detected
[INFO] oc: INFO Copying binaries from /tmp/src/deployments to /deployments ...
[INFO] oc: random-generator-0.0.1.jar
[INFO] oc: INFO Copying deployments from deployments to /deployments...
[INFO] oc: '/tmp/src/deployments/random-generator-0.0.1.jar' -> '/deployments/random-generator-0.0.1.jar'
[INFO] oc: STEP 9: CMD /usr/local/s2i/run
[INFO] oc: STEP 10: COMMIT temp.builder.openshift.io/default/random-generator-s2i-1:48795e41
[INFO] oc: time="2020-08-10T06:37:49Z" level=info msg="Image operating system mismatch: image uses "", expecting "linux""
[INFO] oc: time="2020-08-10T06:37:49Z" level=info msg="Image architecture mismatch: image uses "", expecting "amd64""
[INFO] oc: Getting image source signatures
[INFO] oc: Copying blob sha256:d8e1f35641acb80b562f70cf49911341dfbe8c86f4d522b18efbf3732aa74223
[INFO] oc: Copying blob sha256:b6f081e4b2b6de8be4b1dec132043d14c121e968384dd624fb69c2c07b482edb
[INFO] oc: Copying blob sha256:b7139ad07aa8ce4ed5a132f7c5cc9f1de0f5099b5e155027a23d57f7fbe78b16
[INFO] oc: Copying blob sha256:98972fc90a1108315cc5b05b2c691a0849a149727a7b81e76bc847ac2c6d9714
[INFO] oc: Copying config sha256:27aaadaf28e24856a66db962b88118b8222b61d79163dceeeed869f7289bc230
[INFO] oc: Writing manifest to image destination
[INFO] oc: Storing signatures
[INFO] oc: --> 27aaadaf28e
[INFO] oc: 27aaadaf28e24856a66db962b88118b8222b61d79163dceeeed869f7289bc230
[INFO] oc: Getting image source signatures
[INFO] oc:
[INFO] oc: Pushing image image-registry.openshift-image-registry.svc:5000/default/random-generator:0.0.1 ...
[INFO] oc: Copying blob sha256:f320f94d91a064281f5127d5f49954b481062c7d56cce3b09910e471cf849050
[INFO] oc: Copying blob sha256:cf0f3ebe9f536c782ab3835049cfbd9a663761ded9370791ef6ea3965c823aad
[INFO] oc: Copying blob sha256:57de4da701b511cba33bbdc424757f7f3b408bea741ca714ace265da9b59191a
[INFO] oc: Copying blob sha256:98972fc90a1108315cc5b05b2c691a0849a149727a7b81e76bc847ac2c6d9714
[INFO] oc: Copying config sha256:27aaadaf28e24856a66db962b88118b8222b61d79163dceeeed869f7289bc230
[INFO] oc: Writing manifest to image destination
[INFO] oc: Storing signatures
[INFO] oc: Successfully pushed image-registry.openshift-image-registry.svc:5000/default/random-generator@sha256:aa9e1a380c04ef9174ba56459c13d44420ebe653ebf32884d60fe4306b17306d
[INFO] oc: Push successful
[INFO] oc: Build random-generator-s2i-1 in status Complete
[INFO] oc: Found tag on ImageStream random-generator tag: sha256:aa9e1a380c04ef9174ba56459c13d44420ebe653ebf32884d60fe4306b17306d
[INFO] oc: ImageStream random-generator written to /home/rohaan/work/repos/eclipse-jkube-demo-project/target/random-generator-is.yml
[INFO]
[INFO] --- openshift-maven-plugin:1.0.0-rc-1:resource (default-cli) @ random-generator ---
[INFO] oc: Using docker image name of namespace: default
[INFO] oc: Running generator spring-boot
[INFO] oc: spring-boot: Using Docker image quay.io/jkube/jkube-java-binary-s2i:0.0.7 as base / builder
[INFO] oc: jkube-controller: Adding a default DeploymentConfig
[INFO] oc: jkube-service: Adding a default service 'random-generator' with ports [8080]
[INFO] oc: jkube-healthcheck-spring-boot: Adding readiness probe on port 8080, path='/actuator/health', scheme='HTTP', with initial delay 10 seconds
[INFO] oc: jkube-healthcheck-spring-boot: Adding liveness probe on port 8080, path='/actuator/health', scheme='HTTP', with initial delay 180 seconds
[INFO] oc: jkube-revision-history: Adding revision history limit to 2
[INFO]
[INFO] --- openshift-maven-plugin:1.0.0-rc-1:apply (default-cli) @ random-generator ---
[INFO] oc: Using OpenShift at https://api.crc.testing:6443/ in namespace default with manifest /home/rohaan/work/repos/eclipse-jkube-demo-project/target/classes/META-INF/jkube/openshift.yml
[INFO] oc: OpenShift platform detected
[INFO] oc: Using project: default
[INFO] oc: Creating a Service from openshift.yml namespace default name random-generator
[INFO] oc: Created Service: target/jkube/applyJson/default/service-random-generator.json
[INFO] oc: Creating a DeploymentConfig from openshift.yml namespace default name random-generator
[INFO] oc: Created DeploymentConfig: target/jkube/applyJson/default/deploymentconfig-random-generator.json
[INFO] oc: Creating Route default:random-generator host: null
[INFO] oc: HINT: Use the command `oc get pods -w` to watch your pods start up
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 01:07 min
[INFO] Finished at: 2020-08-10T12:08:00+05:30
[INFO] ------------------------------------------------------------------------
~/work/repos/eclipse-jkube-demo-project : $ oc get pods -w
NAME READY STATUS RESTARTS AGE
random-generator-1-deploy 1/1 Running 0 14s
random-generator-1-vnrm9 0/1 Running 0 11s
random-generator-s2i-1-build 0/1 Completed 0 1m
random-generator-1-vnrm9 1/1 Running 0 24s
random-generator-1-deploy 0/1 Completed 0 28s
~/work/repos/eclipse-jkube-demo-project : $ oc get routes
NAME HOST/PORT PATH SERVICES PORT TERMINATION WILDCARD
random-generator random-generator-default.apps-crc.testing random-generator 8080 None
~/work/repos/eclipse-jkube-demo-project : $ curl random-generator-default.apps-crc.testing/random
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 45 0 45 0 0 1666 0 --:--:-- --:--:-- --:--:-- 1730
{
"id": "d80052d9-2f92-43cb-b9eb-d7cffb879798"
}
~/work/repos/eclipse-jkube-demo-project : $
Video lesson
To learn more about how to simplify Kubernetes development with Eclipse JKube, watch the video tutorial on quickly deploying a simple Spring Boot application on Minikube:
Conclusion
In this article, we showed how Eclipse JKube makes life easier for a Java developer when working with Kubernetes. More information on Eclipse JKube can be found at and .
Source: habr.com