Section 1: Ensure You can connect to the Kubernetes Cluster & create a namespace
jayadmin@cloudshell:~ (kubetrain-331123)$ gcloud container clusters get-credentials virtusa-cluster --zone us-central1-c --project kubetrain-331123
Fetching cluster endpoint and auth data.
kubeconfig entry generated for virtusa-cluster.
jayadmin@cloudshell:~ (kubetrain-331123)$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
gke-virtusa-cluster-default-pool-808e0d91-1fz0 Ready <none> 17h v1.21.5-gke.1302
gke-virtusa-cluster-default-pool-808e0d91-hpdj Ready <none> 17h v1.21.5-gke.1302
gke-virtusa-cluster-default-pool-808e0d91-mb7b Ready <none> 17h v1.21.5-gke.1302
jayadmin@cloudshell:~ (kubetrain-331123)$ kubectl get pods -A
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system event-exporter-gke-5479fd58c8-hdscl 2/2 Running 0 17h
kube-system fluentbit-gke-7xsx5 2/2 Running 0 17h
kube-system fluentbit-gke-927q4 2/2 Running 0 17h
kube-system fluentbit-gke-fqpwr 2/2 Running 0 17h
kube-system gke-metrics-agent-br8xf 1/1 Running 0 17h
kube-system gke-metrics-agent-gvmvx 1/1 Running 0 17h
kube-system gke-metrics-agent-zdnlb 1/1 Running 0 17h
kube-system konnectivity-agent-autoscaler-5c49cb58bb-8mjfg 1/1 Running 0 17h
kube-system konnectivity-agent-f76cf667b-dcjz5 1/1 Running 0 17h
kube-system konnectivity-agent-f76cf667b-dmwn9 1/1 Running 0 17h
kube-system konnectivity-agent-f76cf667b-kxsg6 1/1 Running 0 17h
kube-system kube-dns-697dc8fc8b-lvwrt 4/4 Running 0 17h
kube-system kube-dns-697dc8fc8b-s2z9p 4/4 Running 0 17h
kube-system kube-dns-autoscaler-844c9d9448-h8z68 1/1 Running 0 17h
kube-system kube-proxy-gke-virtusa-cluster-default-pool-808e0d91-1fz0 1/1 Running 0 17h
kube-system kube-proxy-gke-virtusa-cluster-default-pool-808e0d91-hpdj 1/1 Running 0 17h
kube-system kube-proxy-gke-virtusa-cluster-default-pool-808e0d91-mb7b 1/1 Running 0 17h
kube-system l7-default-backend-865b4c8f8b-pwvv5 1/1 Running 0 17h
kube-system metrics-server-v0.4.4-857776bc9c-p9s78 2/2 Running 0 17h
kube-system pdcsi-node-qhcm7 2/2 Running 0 17h
kube-system pdcsi-node-rjrss 2/2 Running 0 17h
kube-system pdcsi-node-sjjj5 2/2 Running 0 17h
jayadmin@cloudshell:~ (kubetrain-331123)$ kubectl get namespace
NAME STATUS AGE
anurag Active 17h
default Active 17h
jagadish Active 16h
jaywant Active 17h
jyothi Active 16h
karimulla Active 17h
kube-node-lease Active 17h
kube-public Active 17h
kube-system Active 17h
mulayam Active 16h
narayana Active 16h
nikhil Active 17h
ramesh Active 16h
sathish Active 17h
vinod Active 16h
vishnavi Active 17h
Create YOUR namespace here kubectl create namespace YOURNAME
jayadmin@cloudshell:~ (kubetrain-331123)$ kubectl create namespace jayaram
namespace/jayaram created
jayadmin@cloudshell:~ (kubetrain-331123)$ kubectl get namespace
NAME STATUS AGE
anurag Active 17h
default Active 17h
jagadish Active 16h
jayaram Active 4s
jaywant Active 17h
jyothi Active 16h
karimulla Active 17h
kube-node-lease Active 17h
kube-public Active 17h
kube-system Active 17h
mulayam Active 16h
narayana Active 16h
nikhil Active 17h
ramesh Active 16h
sathish Active 17h
vinod Active 16h
vishnavi Active 17h
Section 2: Get the Java code and Build it to helloworld.jar
jayadmin@cloudshell:~ (kubetrain-331123)$git clone https://github.com/jayaramcloud/springboot.git
jayadmin@cloudshell:~ (kubetrain-331123)$cd springboot/
Change the ... in the line return "Hello World! Welcome to the World of ..."; with YOUR name
jayadmin@cloudshell:~/springboot$ vi src/main/java/io/kubetrain/tutorial/controller/HelloController.java
package io.kubetrain.tutorial.controller;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
@Controller
public class HelloController {
@RequestMapping("/")
@ResponseBody
String index() {
return "Hello World! Welcome to the World of ...";
}
}
jayadmin@cloudshell:~/springboot$cat Docker
jayadmin@cloudshell:~/springboot$mvn clean package
---------------------
Downloaded from central: https://repo.maven.apache.org/maven2/org/springframework/session/spring-session-bom/Bean-SR6/spring-session-bom-Bean-SR6.pom (3.0 kB at 135 kB/s)
[INFO]
[INFO] ------------------< io.kubetrain.tutorial:helloworld >------------------
[INFO] Building helloworld 1.0
[INFO] --------------------------------[ jar ]---------------------------------
Downloading from central: https://repo.maven.apache.org/maven2/org/springframework/boot/spring-boot-maven-plugin/2.1.6.RELEASE/spring-boot-maven-plugin-2.1.6.RELEASE.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/springframe
---------------------------------
Downloaded from central: https://repo.maven.apache.org/maven2/com/google/guava/guava/19.0/guava-19.0.jar (2.3 MB at 2.9 MB/s)
[INFO] Replacing main artifact with repackaged archive
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 21.162 s
[INFO] Finished at: 2021-12-01T20:48:00Z
[INFO] ------------------------------------------------------------------------
jayadmin@cloudshell:~/springboot$ ls
Dockerfile README.md pom.xml src target
jayadmin@cloudshell:~/springboot$ cd target/;ls
classes generated-sources helloworld.jar helloworld.jar.original maven-archiver maven-status
jayadmin@cloudshell:~/springboot/target$ ls -al
total 16428
drwxr-xr-x 6 jayadmin jayadmin 4096 Dec 1 20:48 .
drwxr-xr-x 5 jayadmin jayadmin 4096 Dec 1 20:47 ..
drwxr-xr-x 3 jayadmin jayadmin 4096 Dec 1 20:47 classes
drwxr-xr-x 3 jayadmin jayadmin 4096 Dec 1 20:47 generated-sources
-rw-r--r-- 1 jayadmin jayadmin 16792328 Dec 1 20:48 helloworld.jar
-rw-r--r-- 1 jayadmin jayadmin 3592 Dec 1 20:47 helloworld.jar.original
drwxr-xr-x 2 jayadmin jayadmin 4096 Dec 1 20:47 maven-archiver
drwxr-xr-x 3 jayadmin jayadmin 4096 Dec 1 20:47 maven-status
jayadmin@cloudshell:~/springboot/target$ cd ..;ls
Dockerfile README.md pom.xml src target
Section 3a: Login to Docker & Build the docker file locally
jayadmin@cloudshell:~/springboot$ cat Dockerfile
FROM openjdk:8-jdk-alpine
# Refer to Maven build -> finalName
WORKDIR /opt/app
COPY target/helloworld.jar app.jar
# java -jar /opt/app/app.jar
ENTRYPOINT ["java","-jar","app.jar"]
Ask Jayaram for the dockerhub login password
jayadmin@cloudshell:~/springboot$ docker login --username kubetrain
Password:
WARNING! Your password will be stored unencrypted in /home/jayadmin/.docker/config.json.
Configure a credential helper to remove this warning. See
https://docs.docker.com/engine/reference/commandline/login/#credentials-store
Login Succeeded
Tag with YOUR name here. for example: docker build -t kubetrain/springboot-demo-YOURNAME:v0.1 .
jayadmin@cloudshell:~/springboot$ docker build -t kubetrain/springboot-demo-jayaram:v0.1 .
Sending build context to Docker daemon 16.92MB
Step 1/4 : FROM openjdk:8-jdk-alpine
8-jdk-alpine: Pulling from library/openjdk
e7c96db7181b: Pull complete
f910a506b6cb: Pull complete
c2274a1a0e27: Pull complete
Digest: sha256:94792824df2df33402f201713f932b58cb9de94a0cd524164a0f2283343547b3
Status: Downloaded newer image for openjdk:8-jdk-alpine
---> a3562aa0b991
Step 2/4 : WORKDIR /opt/app
---> Running in 187f800c07cc
Removing intermediate container 187f800c07cc
---> 46070ad2c79f
Step 3/4 : COPY target/helloworld.jar app.jar
---> 4b81c256ca04
Step 4/4 : ENTRYPOINT ["java","-jar","app.jar"]
---> Running in 98f4a6098b22
Removing intermediate container 98f4a6098b22
---> b0c0de18a9e5
Successfully built b0c0de18a9e5
Successfully tagged kubetrain/springboot-demo-jayaram:v0.1
Section 3c: Ensure that the docker container image is present locally
jayadmin@cloudshell:~/flask-python$ docker image ls
REPOSITORY TAG IMAGE ID CREATED SIZE
kubetrain/flask 0.1 6217b5192b86 About an hour ago 928MB
kubetrain/springboot-demo-jayaram v0.1 b0c0de18a9e5 About a minute ao 122MB
python latest f48ea80eae5a 2 weeks ago 917MB
Section 3c: Start the docker container locally and access it with curl command
jayadmin@cloudshell:~/springboot (kubetrain-331123)$ docker run -p 8081:8081 kubetrain/springboot-demo-jayaram:v0.1
Unable to find image 'kubetrain/springboot-demo-jayaram:v0.1' locally
v0.1: Pulling from kubetrain/springboot-demo-jayaram
e7c96db7181b: Pull complete
f910a506b6cb: Pull complete
c2274a1a0e27: Pull complete
ce9558e19762: Pull complete
790e725d72ff: Pull complete
Digest: sha256:6ce436a7b88dbcd7e2e15c89f97719a4a78b1c42d97107b20e3f476a7aacf155
Status: Downloaded newer image for kubetrain/springboot-demo-jayaram:v0.1
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.1.6.RELEASE)
2021-12-01 21:49:01.269 INFO 1 --- [ main] io.kubetrain.tutorial.AppStart : Starting AppStart v1.0 on ef549877592f with PID 1 (/opt/app/app.jar started by root in /opt/app)
2021-12-01 21:49:01.274 INFO 1 --- [ main] io.kubetrain.tutorial.AppStart : No active profile set, falling back to default profiles: default
2021-12-01 21:49:03.071 INFO 1 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8081 (http)
2021-12-01 21:49:03.139 INFO 1 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2021-12-01 21:49:03.140 INFO 1 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.21]
2021-12-01 21:49:03.317 INFO 1 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2021-12-01 21:49:03.318 INFO 1 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1981 ms
2021-12-01 21:49:03.674 INFO 1 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2021-12-01 21:49:04.098 INFO 1 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8081 (http) with context path ''
2021-12-01 21:49:04.108 INFO 1 --- [ main] io.kubetrain.tutorial.AppStart : Started AppStart in 3.596 seconds (JVM running for 4.165)
#Open another shell and see if you can curl:
jayadmin@cloudshell:~ (kubetrain-331123)$ curl http://localhost:8081
Hello World! Welcome to the World of ...
Section 4: Push it to Dockerhub
jayadmin@cloudshell:~/springboot$ docker push kubetrain/springboot-demo-jayaram:v0.1
The push refers to repository [docker.io/kubetrain/springboot-demo-jayaram]
f51a1c0d8709: Pushed
7125f16a6d7e: Pushed
ceaf9e1ebef5: Mounted from library/openjdk
9b9b7f3d56a0: Mounted from library/openjdk
f1b5933fe4b5: Mounted from library/openjdk
v0.1: digest: sha256:6ce436a7b88dbcd7e2e15c89f97719a4a78b1c42d97107b20e3f476a7aacf155 size: 1366
# Visist https://hub.docker.com/repositories and login as kubetrain and check if the new image is present.