docker-build-push

---

name: docker-build-push description: Build and push multi-platform Docker images to Google Artifact Registry. Use when user asks to build, push, or deploy a Docker image with a tag. Triggers: "build and push", "push docker image", "build with tag", "deploy image".

Docker Build and Push

Build and push multi-platform Docker images to the melosys-api Google Artifact Registry.

This repo-local skill intentionally overrides the global docker-build-push, which auto-detects the image name from the cwd (basename of the git root) and would mis-name images in parallel checkouts like melosys-api-claude.

Image name — ALWAYS melosys-api

The image repository is always melosys-api, never the cwd directory name. Parallel workspaces may be checked out as melosys-api-claude, melosys-api-2, etc., but the published image name never changes.

Registry

europe-north1-docker.pkg.dev/nais-management-233d/teammelosys/melosys-api

Build and Push Command

docker buildx build --platform linux/amd64,linux/arm64 \
  -t europe-north1-docker.pkg.dev/nais-management-233d/teammelosys/melosys-api:TAG \
  --push .

Replace TAG with user-specified tag.

Workflow

The Dockerfile is single-stage (distroless) and copies a pre-built JAR (COPY /app/target/melosys-sb-execution.jar) — it does NOT build the JAR itself. So you must produce the JAR before the buildx build whenever code changed or app/target/ has no current JAR.

1. Build the JAR first: make build-fast (mvn clean install -DskipTests)
2. Run buildx build with --push — keep the image path exactly as shown above
3. Report: tag, platforms, manifest digest
4. Before reporting "done", verify the -t argument ends with /melosys-api:TAG (not /melosys-api-claude:TAG or any other variant)

Setup (if buildx not configured)

docker buildx create --name multiplatform --use --driver docker-container || docker buildx use multiplatform

Error Handling

Authentication expired

Message: "Reauthentication failed" Solution: Ask user to run gcloud auth login, then retry

No matching manifest for linux/amd64

Cause: Image built only for arm64 Solution: Use --platform linux/amd64,linux/arm64 flag

Output Format

After successful push:

Done!

Image details:
- Tag: europe-north1-docker.pkg.dev/.../melosys-api:TAG
- Platforms: linux/amd64, linux/arm64
- Manifest digest: sha256:...