scaffold: adjust Dockerfile template to support multi-arch builds

Author: cbarbian-sap

scaffold/templates/Dockerfile.tpl

@@ -1,35 +1,33 @@
 # Build the manager binary
-FROM golang:{{ .goVersion }} as builder
+FROM --platform=$BUILDPLATFORM golang:{{ .goVersion }} as builder
 ARG TARGETOS
 ARG TARGETARCH
 
 WORKDIR /workspace
 # Copy the Go Modules manifests
 COPY go.mod go.mod
 COPY go.sum go.sum
-# cache deps before building and copying source so that we don't need to re-download as much
+# Cache deps before building and copying source so that we don't need to re-download as much
 # and so that source changes don't invalidate our downloaded layer
 RUN go mod download
 
-# Copy the go source
+# Copy the go sources
 COPY main.go main.go
 COPY api/ api/
 COPY pkg/ pkg/
-COPY hack/ hack/
+COPY crds/ crds/
 COPY Makefile Makefile
 
-# Build
-# the GOARCH has not a default value to allow the binary be built according to the host where the command
-# was called. For example, if we call make docker-build in a local env which has the Apple Silicon M1 SO
-# the docker BUILDPLATFORM arg will be linux/arm64 when for Apple x86 it will be linux/amd64. Therefore,
-# by leaving it empty we can ensure that the container and binary shipped on it will have the same platform.
-RUN CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} make test build
+# Run tests and build
+RUN make envtest \
+ && CGO_ENABLED=0 KUBEBUILDER_ASSETS="/workspace/bin/k8s/current" go test ./... \
+ && CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build -a -o manager main.go
 
 # Use distroless as minimal base image to package the manager binary
 # Refer to https://github.com/GoogleContainerTools/distroless for more details
 FROM gcr.io/distroless/static:nonroot
 WORKDIR /
-COPY --from=builder /workspace/bin/manager .
+COPY --from=builder /workspace/manager .
 USER 65532:65532
 
 ENTRYPOINT ["/manager"]