FROM scratch as base
ENV VERSION=1.29
ENV SRC_HASH=d1f1c9c44c425809718edab34c884c4dd9fd6c18396d779d5bd444da2d420792
ENV SRC_FILE=release-${VERSION}.tar.gz
ENV SRC_SITE=https://github.com/kubernetes/kubernetes/archive/refs/heads/${SRC_FILE}
ENV GOPATH=/cache/go
ENV GOCACHE=/cache/
ENV GOWORK=off
ENV GOPROXY=https://proxy.golang.org,direct
ENV GOSUMDB=sum.golang.org
ENV CGO_ENABLED=0
ENV GOHOSTOS=linux
ENV GOHOSTARCH=amd64

FROM base as fetch
COPY --from=stagex/busybox . /
COPY --from=stagex/go . /
COPY --from=stagex/ca-certificates . /
ADD --checksum=sha256:${SRC_HASH} ${SRC_SITE} .
RUN tar -xvf ${SRC_FILE}
WORKDIR kubernetes-release-${VERSION}
RUN go get ./...

FROM fetch as build
RUN --network=none go build -trimpath -v k8s.io/kubernetes/cmd/kubectl

from build as install
RUN <<-EOF
    mkdir -p /rootfs/usr/bin/
    cp kubectl /rootfs/usr/bin/
    find /rootfs -exec touch -hcd "@0" "{}" +
EOF

FROM stagex/filesystem as package
COPY --from=install /rootfs/./ /