Migrate to Docker Buildx for multi-architecture builds - ARM64 support currently commented

[Kaushik-Vijayakumar]

Problem Description

The repository claims to support multi-architecture Docker images, but currently only builds for AMD64 architecture. This makes the Docker images unusable on ARM-based systems (Apple Silicon Macs, ARM64 servers, etc.).

Current Issues:

1. Only AMD64 builds enabled: In scripts/build/docker/build-publish-image-all.sh, line 17 shows that ARM64 and other architectures are commented out:

   #archs=("amd64" "arm64" "arm" "ppc64le" "s390x")
   archs=("amd64")  # Only building AMD64

2. Outdated build approach: The current build process uses the older, complex approach of building separate images per architecture and manually creating Docker manifests, which is error-prone and harder to maintain.

3. User experience: Users on ARM systems (M1/M2 Macs, ARM64 servers) cannot use the published Docker images, despite documentation suggesting multi-arch support.

Solution: Migrate to Docker Buildx

The build process should be migrated to Docker Buildx for true multi-architecture builds. This is the modern Docker standard used by most contemporary projects including Kubernetes, Prometheus, and other CNCF projects.

Benefits:
✅ Simplify the build process - Single command instead of complex shell scripts
✅ Enable true multi-arch - All architectures built and pushed together automatically
✅ Improve maintainability - Less custom scripting, more standard Docker tooling
✅ Better user experience - docker pull works seamlessly on any architecture
✅ Future-proof - Buildx is the industry standard for multi-arch builds

Implementation

Replace the current build scripts with a buildx-based approach:

# Example buildx command
docker buildx build \
  --platform linux/amd64,linux/arm64,linux/arm/v7,linux/ppc64le,linux/s390x \
  --push \
  -t ghcr.io/slok/kube-code-generator:${VERSION} \
  -f docker/prod/Dockerfile .

This would:

• Eliminate the need for separate per-arch builds
• Remove manual manifest creation/annotation steps
• Simplify CI/CD workflows significantly
• Provide better error handling and logging
• Enable all the currently commented architectures

Impact

• Users: Can use Docker images on any architecture without worrying about compatibility
• Maintainers: Simpler, more reliable build process with less maintenance overhead
• CI/CD: Faster builds and reduced complexity
• Alignment: Implementation matches documentation claims of multi-arch support

Implementation Plan

I will implement this migration to enable all the currently commented architectures (amd64, arm64, arm, ppc64le, s390x) using Docker Buildx. The current Dockerfile already includes ARG ARCH for cross-compilation, so it's ready for this change.