Buildpack Library Requirements Gathering

[BarDweller]

Requirements Questions: These need answers from people who might consume this client as a library...

• where do we need our target images to go ? local daemon vs remote registry / with/without auth ?
• do we have a stack we should be using instead of the paketo one? (buildImage/runImage pair)
• do we have custom buildpack content we want to use via this? (would be present in a spec formatted directory as an arg)
• do we want to pass custom env vars to the final image? (assume map string>string is fine?)
• how will application content be specified (File/Directory/Programmatically supplied as Path/size/inputstream per entry)
• what kind of log/feedback is required during execution?
• do we want the buildpack to assemble from a war/uber-jar, or let it build from source, and take care of everything?
• can we tell if a build is for 'the same application' (allowing us to reuse cache volumes), how can this be indicated to the builder?

[BarDweller]

Current capabilities: https://github.com/BarDweller/java-buildpack-client/blob/main/src/com/redhat/buildpack/BuildPackBuilder.java

• Target image name configurable via API
• Custom Builder/Run Images configurable via API (allows for custom builder image selection, which is one way to coordinate buildpacks, may also need to consider a buildpack dir addon approach, if required)
• Env var during build 50% complete (API in place, not hooked to build phase yet)
• Variety of methods provided for adding application content to be built by buildpack, including String, InputStream, File/Directory, and Custom Abstraction interface.
• LogLevel of Buildpack exec configurable via API. (including timestamp inclusion or not)
• Cache Volume names configurable via API (allowing for a project to decide a cache volume name, so the cache is reused for subsequent builds of that project)
• Configurable pull timeout for build/run images

TODO:

• Docker Registry instead of Docker Daemon Support (requires config for registry auth)
• Buildpack addon dir support
• Custom Buildpack for Quarkus (and/or Quarkus Native)

[BarDweller]

Looking at https://quarkus.io/guides/container-image (and the corresponding code for the jib/docker/s2i extensions) to understand what they provide/offer, and how well that will mesh with the Buildpack model.

Need to confirm Quarkus project behavior with the paketo.io Java buildpack. Expect regular project to work, but Native will likely require a custom buildpack (either via builder image, or via buildpack addon dir)

[BarDweller]

This one hasn't gone totally quiet.. =)

Will need to add support to the Java Buildpack Client to allow builds against a Docker Registry, which will mean passing Configuration information.

Some progress being made re if the Quarkus Builder Image will be in a registry somewhere that the client can pull from too.

[BarDweller]

Closing this one, as the library now has it's own snowdrop docker repo, where future enhancements can be tracked as Issues.