I have created an azure devops project for java , spring boot and kubernetes as a way to learn about the azure technology set. It does work , the simple spring boot web application is deployed and runs and is rebuilt if I make code changes.

However the spring boot application uses a very old version of spring 1.5.7.RELEASE and it is deployed in a tomcat server in k8s.

I am looking for some guidance on how to run it as a standalone spring boot version 2 application in kubernetes. My attempts so far have resulted in the deployment timing out after 15 minutes in the Helm Upgrade step.

The existing docker file

FROM maven:3.5.2-jdk-8 AS build-env
WORKDIR /app
COPY . /app
RUN mvn package

FROM tomcat:8
RUN rm -rf /usr/local/tomcat/webapps/ROOT
COPY --from=build-env /app/target/*.war /usr/local/tomcat/webapps/ROOT.war

How to change the dockerfile to build the image of a standalone spring boot app?

I changed the pom to generate a jar file, then modified the docker file to this:

FROM maven:3.5.2-jdk-8 AS build-env
WORKDIR /app
COPY . /app
RUN mvn package

FROM openjdk:8-jdk-alpine
VOLUME /tmp
COPY --from=build-env  /app/target/ROOT.jar .
RUN ls -la
ENTRYPOINT ["java","-jar","ROOT.jar"]

This builds, see output from the log for 'Build an image' step

...
2019-06-25T23:33:38.0841365Z Step 9/20 : COPY --from=build-env  /app/target/ROOT.jar .
2019-06-25T23:33:41.4839851Z  ---> b478fb8867e6
2019-06-25T23:33:41.4841124Z Step 10/20 : RUN ls -la
2019-06-25T23:33:41.6653383Z  ---> Running in 4618c503ac5c
2019-06-25T23:33:42.2022890Z total 50156
2019-06-25T23:33:42.2026590Z drwxr-xr-x    1 root     root          4096 Jun 25 23:33 .
2019-06-25T23:33:42.2026975Z drwxr-xr-x    1 root     root          4096 Jun 25 23:33 ..
2019-06-25T23:33:42.2027267Z -rwxr-xr-x    1 root     root             0 Jun 25 23:33 .dockerenv
2019-06-25T23:33:42.2027608Z -rw-r--r--    1 root     root      51290350 Jun 25 23:33 ROOT.jar
2019-06-25T23:33:42.2027889Z drwxr-xr-x    2 root     root          4096 May  9 20:49 bin
2019-06-25T23:33:42.2028188Z drwxr-xr-x    5 root     root           340 Jun 25 23:33 dev
2019-06-25T23:33:42.2028467Z drwxr-xr-x    1 root     root          4096 Jun 25 23:33 etc
2019-06-25T23:33:42.2028765Z drwxr-xr-x    2 root     root          4096 May  9 20:49 home
2019-06-25T23:33:42.2029376Z drwxr-xr-x    1 root     root          4096 May 11 01:32 lib
2019-06-25T23:33:42.2029682Z drwxr-xr-x    5 root     root          4096 May  9 20:49 media
2019-06-25T23:33:42.2029961Z drwxr-xr-x    2 root     root          4096 May  9 20:49 mnt
2019-06-25T23:33:42.2030257Z drwxr-xr-x    2 root     root          4096 May  9 20:49 opt
2019-06-25T23:33:42.2030537Z dr-xr-xr-x  135 root     root             0 Jun 25 23:33 proc
2019-06-25T23:33:42.2030937Z drwx------    2 root     root          4096 May  9 20:49 root
2019-06-25T23:33:42.2031214Z drwxr-xr-x    2 root     root          4096 May  9 20:49 run
2019-06-25T23:33:42.2031523Z drwxr-xr-x    2 root     root          4096 May  9 20:49 sbin
2019-06-25T23:33:42.2031797Z drwxr-xr-x    2 root     root          4096 May  9 20:49 srv
2019-06-25T23:33:42.2032254Z dr-xr-xr-x   12 root     root             0 Jun 25 23:33 sys
2019-06-25T23:33:42.2032355Z drwxrwxrwt    2 root     root          4096 May  9 20:49 tmp
2019-06-25T23:33:42.2032656Z drwxr-xr-x    1 root     root          4096 May 11 01:32 usr
2019-06-25T23:33:42.2032945Z drwxr-xr-x    1 root     root          4096 May  9 20:49 var
2019-06-25T23:33:43.0909881Z Removing intermediate container 4618c503ac5c
2019-06-25T23:33:43.0911258Z  ---> 0d824ce4ae62
2019-06-25T23:33:43.0911852Z Step 11/20 : ENTRYPOINT ["java","-jar","ROOT.jar"]
2019-06-25T23:33:43.2880002Z  ---> Running in bba9345678be
...

The build completes but deployment fails in the Helm Upgrade step, timing out after 15 minutes. This is the log

2019-06-25T23:38:06.6438602Z ##[section]Starting: Helm upgrade
2019-06-25T23:38:06.6444317Z ==============================================================================
2019-06-25T23:38:06.6444448Z Task         : Package and deploy Helm charts
2019-06-25T23:38:06.6444571Z Description  : Deploy, configure, update a Kubernetes cluster in Azure Container Service by running helm commands
2019-06-25T23:38:06.6444648Z Version      : 0.153.0
2019-06-25T23:38:06.6444927Z Author       : Microsoft Corporation
2019-06-25T23:38:06.6445006Z Help         : https://docs.microsoft.com/azure/devops/pipelines/tasks/deploy/helm-deploy
2019-06-25T23:38:06.6445300Z ==============================================================================
2019-06-25T23:38:09.1285973Z [command]/opt/hostedtoolcache/helm/2.14.1/x64/linux-amd64/helm upgrade --tiller-namespace dev2134 --namespace dev2134 --install --force --wait --set image.repository=stephenacr.azurecr.io/stephene991 --set image.tag=20 --set applicationInsights.InstrumentationKey=643a47f5-58bd-4012-afea-b3c943bc33ce --set imagePullSecrets={stephendockerauth} --timeout 900 azuredevops /home/vsts/work/r1/a/Drop/drop/sampleapp-v0.2.0.tgz
2019-06-25T23:53:13.7882713Z UPGRADE FAILED
2019-06-25T23:53:13.7883396Z Error: timed out waiting for the condition
2019-06-25T23:53:13.7885043Z Error: UPGRADE FAILED: timed out waiting for the condition
2019-06-25T23:53:13.7967270Z ##[error]Error: UPGRADE FAILED: timed out waiting for the condition

2019-06-25T23:53:13.7976964Z ##[section]Finishing: Helm upgrade