fix: Split local image build into build and publish workflows#730
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lindnerby merged 5 commits intoMay 7, 2026
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Adds image-builder-local.yml to build and publish runtime-watcher images to ghcr.io/kyma-project/runtime-watcher for fast local testing on arm64 (Apple M-series) and amd64 machines. Closes kyma-project#709
- Rename image-builder-local.yml → build-image-local.yml - Remove draft PR guard — builds run for draft PRs too - Rename workflow display name to "Build Image (Local testing / ghcr.io)"
Addresses the pull_request_target supply-chain vulnerability flagged by GitHub code scanning. Follows the workflow_run split pattern: - build-image-local.yml: runs on pull_request (untrusted, no secrets), builds multi-arch OCI tarball and uploads as artifact - publish-image-local.yml: runs on workflow_run (privileged, never executes fork code), pushes tarball to ghcr.io via skopeo Improvements over the original fix: - Guard against empty tags with explicit error message - Push from OCI archive directly to all tags (no registry round-trip) - Print image digest in job summary for digest pinning
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medmes
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Remove metadata.json from the build workflow entirely — fork code could forge event_name/ref to hijack the :latest tag. Tag decisions are now derived exclusively from github.event.workflow_run.* (trusted GitHub context) in the publish workflow, which never executes untrusted code.
Move workflow_run context values (head_branch, head_sha, event) from
inline ${{ }} expressions into env variables to prevent shell injection
via maliciously-named branches.
lindnerby
approved these changes
May 7, 2026
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Description
Addresses the
pull_request_targetsupply-chain vulnerability flagged by GitHub code scanning after #711 was merged.The single workflow is split into two:
build-image-local.yml: runs onpull_request(untrusted context, no secrets) — builds multi-arch OCI tarball and uploads as a GitHub Actions artifactpublish-image-local.yml: runs onworkflow_run(privileged, base branch context) — downloads the pre-built artifact and pushes toghcr.ioviaskopeo. Never checks out fork code.This eliminates the risk of fork-controlled
Dockerfilecontent executing in a context withpackages: write.Additional improvements over the baseline fix:
tagswith an explicit error message