In this blog post, I will talk about how easily you can create a scaffold for your Java based application and deploy it. TAP make this very easy for us with the help of accelerators and it also comes with few out of the box accelerators. We will be using accelerator to generate a scaffold and then deploy the application.
#1 Use Case: Developing Application
Thinking from a developer perspective, you are planning to develop a Java based application and deploy it on a Kubernete platform without knowing the complexity of the underlying Kubernetes platform.
So, as a developer, you will get readymade accelerators to speedup the application development.
Let’s create the scaffold for your application now.
– Login to TAP GUI
– Navigate to the Create option
– Choose Tanzu Java Web App
– Provide the required detail as shown in the below screenshot.
Remember:
Image Repository name is a combination of SERVER/REPOSITORY-NAME you have provided in tap-values.yaml file during tap install/update.
Name, You can provide the application name or leave the default one.
– You can also explore the project by clicking on EXPLORE button and the following detail will be displayed.
– Explore the important files like config/workload.yaml and Tiltfile. I will talk about these files in detail later on.
– Click on the Next Step button
– Click on the Create button and this will generate a zip file for you.
– Download the zip file, unzip and open the Java project. I am using Visual Studio Code and would recommend to use that because in later parts, I will be talking about the Tanzu plugin for VSCode that helps you as a developer to accelerate the application changes.
$ unzip tanzu-java-web-app.zip
Archive: tanzu-java-web-app.zip
creating: tanzu-java-web-app/
extracting: tanzu-java-web-app/.gitignore
creating: tanzu-java-web-app/.mvn/
creating: tanzu-java-web-app/.mvn/wrapper/
extracting: tanzu-java-web-app/.mvn/wrapper/MavenWrapperDownloader.java
extracting: tanzu-java-web-app/.mvn/wrapper/maven-wrapper.jar
extracting: tanzu-java-web-app/.mvn/wrapper/maven-wrapper.properties
extracting: tanzu-java-web-app/LICENSE
extracting: tanzu-java-web-app/README.md
extracting: tanzu-java-web-app/Tiltfile
extracting: tanzu-java-web-app/accelerator-log.md
extracting: tanzu-java-web-app/catalog-info.yaml
creating: tanzu-java-web-app/config/
extracting: tanzu-java-web-app/config/workload.yaml
extracting: tanzu-java-web-app/mvnw
extracting: tanzu-java-web-app/mvnw.cmd
extracting: tanzu-java-web-app/pom.xml
creating: tanzu-java-web-app/src/
creating: tanzu-java-web-app/src/main/
creating: tanzu-java-web-app/src/main/java/
creating: tanzu-java-web-app/src/main/java/com/
creating: tanzu-java-web-app/src/main/java/com/example/
creating: tanzu-java-web-app/src/main/java/com/example/springboot/
extracting: tanzu-java-web-app/src/main/java/com/example/springboot/Application.java
extracting: tanzu-java-web-app/src/main/java/com/example/springboot/HelloController.java
creating: tanzu-java-web-app/src/main/resources/
extracting: tanzu-java-web-app/src/main/resources/application.yml
creating: tanzu-java-web-app/src/test/
creating: tanzu-java-web-app/src/test/java/
creating: tanzu-java-web-app/src/test/java/com/
creating: tanzu-java-web-app/src/test/java/com/example/
creating: tanzu-java-web-app/src/test/java/com/example/springboot/
extracting: tanzu-java-web-app/src/test/java/com/example/springboot/HelloControllerTest.java
$
$ ls
tanzu-java-web-app – I am pushing the code in my github repository. You can do the same but use your github repository.
$ git remote add origin https://github.com/dineshtripathi30/tanzu-java-web-app.git
(main) $ git branch -M main
(main) $ git push -u origin main
Enumerating objects: 34, done.
Counting objects: 100% (34/34), done.
Delta compression using up to 12 threads
Compressing objects: 100% (24/24), done.
Writing objects: 100% (34/34), 60.36 KiB | 10.06 MiB/s, done.
Total 34 (delta 0), reused 0 (delta 0), pack-reused 0
To https://github.com/dineshtripathi30/tanzu-java-web-app.git
* [new branch] main -> main
Branch 'main' set up to track remote branch 'main' from 'origin'.So, here the development part is completed. Now, lets deploy the application.
#2 Use Case: Deploying Application
Deploying application is very easy and you do not have to worry about writing a complex Dockerfile, yaml files etc. Just run the below tanzu command to deploy this application.
$ tanzu apps workload create tanzu-java-web-app \
> --git-repo https://github.com/dineshtripathi30/tanzu-java-web-app \
> --git-branch main \
> --type web \
> --label app.kubernetes.io/part-of=tanzu-java-web-app \
> --yes
Create workload:
1 + |---
2 + |apiVersion: carto.run/v1alpha1
3 + |kind: Workload
4 + |metadata:
5 + | labels:
6 + | app.kubernetes.io/part-of: tanzu-java-web-app
7 + | apps.tanzu.vmware.com/workload-type: web
8 + | name: tanzu-java-web-app
9 + | namespace: default
10 + |spec:
11 + | source:
12 + | git:
13 + | ref:
14 + | branch: main
15 + | url: https://github.com/dineshtripathi30/tanzu-java-web-app
Created workload "tanzu-java-web-app"
– Keep watching the pod status as it will take sometime to build and deploy the application. TAP internally uses Tanzu Build Service (TBS) for turning application source code to a container image.
– Run the below command to see the status of application deployment.
$ tanzu apps workload tail tanzu-java-web-app --since 10m --timestamp– Run the below command after few mins and you will see the status in detail.
$ tanzu apps workload get tanzu-java-web-app
# tanzu-java-web-app: Ready
---
lastTransitionTime: "2021-12-27T04:32:03Z"
message: ""
reason: Ready
status: "True"
type: Ready
Workload pods
NAME STATE AGE
tanzu-java-web-app-build-1-build-pod Succeeded 56m
tanzu-java-web-app-config-writer-kmlfp-pod Succeeded 55m
Workload Knative Services
NAME READY URL
tanzu-java-web-app Ready http://tanzu-java-web-app.default.example.com
– Run the below command to get other objects
$ kubectl get workload,gitrepository,pipelinerun,images.kpack,podintent,app,services.serving
NAME AGE
workload.carto.run/tanzu-java-web-app 8m32s
NAME URL READY STATUS AGE
gitrepository.source.toolkit.fluxcd.io/tanzu-java-web-app https://github.com/dineshtripathi30/tanzu-java-web-app True Fetched revision: main/c593c74131cada0f0a723b36b649b08528e90edc 8m29s
NAME LATESTIMAGE READY
image.kpack.io/tanzu-java-web-app demo-registry.com/build-service/tanzu-java-web-app-default@sha256:11299229f883996dd8229ef6f1b644e0ec1758645953c23edade68ad7ca49dcb True
NAME READY REASON AGE
podintent.conventions.apps.tanzu.vmware.com/tanzu-java-web-app True 7m23s
NAME DESCRIPTION SINCE-DEPLOY AGE
app.kappctrl.k14s.io/tanzu-java-web-app Reconcile succeeded 14s 6m19s
NAME URL LATESTCREATED LATESTREADY READY REASON
service.serving.knative.dev/tanzu-java-web-app http://tanzu-java-web-app.default.example.com tanzu-java-web-app-00001 tanzu-java-web-app-00001 # Please edit the object below. Lines beginning with a '#' will be ignored,
True
That’s all for this post, In the upcoming TAP part #, I will be talking about how easily you can make the changes on this application and live update using Tanzu plugin for VSCode.
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