[EPIC] Buildpacks-based container image build strategy

[manusa]

Description

As a user, I want to be able to use Eclipse JKube to build container images and deploy them to a Kubernets-compatible cluster for my Java application leveraging Buildpacks, so that I can take advantage and reuse one of the many production ready buildpacks to create an image for my application.

Buildpacks is used by many frameworks, such as Spring Boot, to create container images for an application. There is a curated, community-maintained, growing list of buildpacks to support all kinds of frameworks, libraries, and programming languages.

Currently, JKube can be made compatible with Buildpacks-produced container images by tuning the image name at the buildpacks level, or modifying JKube's resource configuration.
However, this is cumbersome and requires the user to provide additional configurations.

It would be good to have a transparent, seamless integration with Buildpacks (similar to what we have for Jib). This way, a user wouldn't need to worry about additional configurations and could simply leverage Buildpacks by configuring it as JKube's container image build strategy.

Tasks

• Spike a PoC implementation to see if this is possible
• Draft a design document
  https://docs.google.com/document/d/1HYSEad6pLBvtHJqyCmNdUUTE3lhIdCDd1AtmA5p-9MY/
• Create individual development tasks and stories
  • [US] Buildpacks with opinionated defaults (Zero config) #2465
    • Buildpacks CLI (pack) controller #2453
    • Buildpacks CLI (pack) downloader #2454
      • Add utility class to decompress archive files #2456
    • Buildpacks build service #2493
    • Buildpacks Maven integration #2491
    • Buildpacks Gradle integration #2492
    • k8s:push/k8sPush should work with buildpacks build strategy #2464
  • [US] Configure buildpack builder image #2470
  • [US] Configure buildpacks image configuration through JKube's image configuration #2459
  • Add documentation for Buildpacks related functionality #2466
  • [US] Buildpacks unsupported Maven/Gradle goals/tasks #2494
    • k8s:watch/k8sWatch should throw error in buildpacks build strategy #2461
    • k8s:debug throws error when using buildpacks build strategy #2462
  • Implement E2E tests for buildpacks build strategy #3097

To be discussed later:

• JKube generators should be able to provide opinionated BuildPackConfiguration #2460

• Cache buildpack builds in a local docker volume #2463

See also:

• https://buildpacks.io/
• https://github.com/paketo-buildpacks
• https://github.com/spring-projects/spring-boot/tree/3657c6c85de0bd49529d2dc256dd4350b61ad7c1/spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform

Relates to:

• Support for podman/buildah #66

[manusa]

https://github.com/snowdrop/java-buildpack-client

[rohanKanojia]

Shall we close this one? The only open issue should be closed by eclipse-jkube/jkube-integration-tests#371