port kindnetd to buildkit

images/kindnetd/Dockerfile

@@ -12,7 +12,14 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-ARG GOARCH=amd64
-FROM gcr.io/google-containers/debian-iptables-${GOARCH}:v12.0.1
-COPY --chown=root:root kindnetd /bin/kindnetd
+# first stage build kindnetd binary
+# NOTE: tentatively follow upstream kubernetes go version based on k8s in go.mod
+FROM golang:1.13
+WORKDIR /go/src
+COPY . .
+RUN CGO_ENABLED=0 go build -o ./kindnetd ./cmd/kindnetd
+
+# build real kindnetd image
+FROM gcr.io/google-containers/debian-iptables:v12.0.1
+COPY --from=0 --chown=root:root ./go/src/kindnetd /bin/kindnetd
 CMD ["/bin/kindnetd"]

images/kindnetd/Makefile

@@ -0,0 +1,29 @@
+TAG?=$(shell echo "$$(date +v%Y%m%d)-$$(git describe --always --dirty)")
+IMAGE?=kindest/kindnetd:$(TAG)
+# required for buildx
+export DOCKER_CLI_EXPERIMENTAL=enabled
+
+# build with buildx
+PLATFORMS?=linux/amd64,linux/arm64,linux/arm,linux/ppc64le
+OUTPUT=
+PROGRESS=auto
+build: ensure-buildx
+	docker buildx build --platform=${PLATFORMS} $(OUTPUT) --progress=$(PROGRESS) -t ${IMAGE} --pull .
+
+# push the cross built image
+push: OUTPUT=--push
+push: build
+
+# quick can be used to do a build that will be imported into the local docker 
+# for sanity checking before doing a cross build push
+# cross builds cannot be imported locally at the moment
+# https://github.com/docker/buildx/issues/59
+quick: PLATFORMS=linux/amd64
+quick: OUTPUT=--load
+quick: build
+
+# enable buildx
+ensure-buildx:
+	./../../hack/build/init-buildx.sh
+
+.PHONY: push build quick ensure-buildx