spring-buildpacks-poc

POC using Spring Boot and create image with buildpacks

This POC is being make based on instructions from this site, but using Spring Gradle plugin instead Spring Maven plugin.

What are Cloud Native Buildpacks?

From https://buildpacks.io

"The Cloud Native Buildpacks project was initiated by Pivotal and Heroku in January 2018 and joined the Cloud Native Sandbox in October 2018. The project aims to unify the buildpack ecosystems with a platform-to-buildpack contract that is well-defined and that incorporates learnings from maintaining production-grade buildpacks for years at both Pivotal and Heroku."

Buildpacks provide a higher-level abstraction for building applications compared to Dockerfiles. The job of a buildpack is to detect and gather everything your application needs to build and run.

Long story short, a buildpack will transform your source code into a runnable application image!

Prerequisites

Make sure you have Docker installed. If not, install Docker (optionally install Docker Compose as well).

Verify Docker:

$ docker -v
Docker version 19.03.8, build afacb8b7f0

And optionally Docker Compose:

$ docker-compose -v
docker-compose version 1.25.0, build unknown

Building docker image

Now package the application source code into an OCI image using the Spring Boot Gradle plugin and buildpacks:

$ gradle bootBuildImage

You can check that Gradle will start to create the image with name docker.io/library/buildpack-demo:0.0.1-SNAPSHOT.

To do that it will pull buildpack builder/runtime images from paketo-buildpacks and, after that, start to create the image.

When the build succeeds, you should be able to see the image using Docker:

docker images |grep buildpack-demo                                                                                 ░▒▓ ✔ 
buildpack-demo    0.0.1-SNAPSHOT   fd0862cad8fb     40 years ago    266MB

##Run the application using Docker Now it’s time to start a container via Docker.

$ docker run -d -p 8080:8080 --name springbootcontainer buildpack-demo:0.0.1-SNAPSHOT                                ░▒▓ ✔

Check whether or not the container is running:

$ docker ps
CONTAINER ID        IMAGE                           COMMAND                  CREATED             STATUS              PORTS                                        NAMES
9c86ed8828f7        buildpack-demo:0.0.1-SNAPSHOT   "/cnb/lifecycle/laun…"   12 seconds ago      Up 5 seconds        0.0.0.0:8080->8080/tcp

Now hit http://localhost:8080 in your favorite browser to see the greeting from the simple Spring MVC Rest controller. Excellent, the application is up and running in the container!

Also take a look at the Spring Boot info actuator endpoint: http://localhost:8080/actuator/info

You can verify the Spring Boot application is running on Bellsoft version 11.0.8. The show the Java and application details customize the Spring Boot info actuator in your application.yml configuration file. The version can change based on image updates by Paketo.

To stop the container run:

$ docker stop springbootcontainer

Reference Documentation

For further reference, please consider the following sections:

Guides

The following guides illustrate how to use some features concretely:

Additional Links

These additional references should also help you:

Gradle Build Scans – insights for your project's build