Build desired target with a buildargument

This way we are not diverging in multiple dockerfiles and we can choose between two targets:
- cilium-cli-ci The original target based on ubuntu and the default
- cilium-cli Only contains the cilium cli based on scratch

Fixes: cilium#2755

Signed-off-by: Merijn Keppel <[email protected]>

.github/workflows/images.yaml

@@ -67,7 +67,9 @@ jobs:
           context: .
           file: ${{ matrix.dockerfile }}
           push: true
-          platforms: linux/amd64
+          platforms: ${{ matrix.platforms }}
+          build-args: |
+            FINAL_CONTAINER=${{ matrix.name }}
           tags: |
             quay.io/${{ github.repository_owner }}/${{ matrix.name }}:latest
             quay.io/${{ github.repository_owner }}/${{ matrix.name }}:${{ steps.tag.outputs.tag }}
@@ -90,6 +92,8 @@ jobs:
           file: ${{ matrix.dockerfile }}
           push: true
           platforms: ${{ matrix.platforms }}
+          build-args: |
+            FINAL_CONTAINER=${{ matrix.name }}
           tags: |
             quay.io/${{ github.repository_owner }}/${{ matrix.name }}:${{ steps.tag.outputs.tag }}
 

Dockerfile

@@ -3,15 +3,23 @@
 # Copyright Authors of Cilium
 # SPDX-License-Identifier: Apache-2.0
 
+# FINAL_CONTAINER specifies the source for the output
+# cilium-cli-ci (default) is based on ubuntu with cloud CLIs
+# cilium-cli is from scratch only including cilium binaries
+ARG FINAL_CONTAINER="cilium-cli-ci"
+
 FROM docker.io/library/golang:1.22.6-alpine3.19@sha256:1bad39361dd21f2f881ce10ff810e40e5be3eba89a0b61e762e05ec42f9bbaf2 AS builder
 WORKDIR /go/src/github.com/cilium/cilium-cli
 RUN apk add --no-cache git make ca-certificates
 COPY . .
 RUN make
 
-FROM ubuntu:24.04@sha256:8a37d68f4f73ebf3d4efafbcf66379bf3728902a8038616808f04e34a9ab63ee
+FROM scratch AS cilium-cli
+LABEL maintainer="[email protected]"
+COPY --from=builder /go/src/github.com/cilium/cilium-cli/cilium /usr/local/bin/cilium
+
+FROM ubuntu:24.04@sha256:8a37d68f4f73ebf3d4efafbcf66379bf3728902a8038616808f04e34a9ab63ee AS cilium-cli-ci
 LABEL maintainer="[email protected]"
-WORKDIR /root/app
 COPY --from=builder /go/src/github.com/cilium/cilium-cli/cilium /usr/local/bin/cilium
 
 # Install cloud CLIs. Based on these instructions:
@@ -31,4 +39,8 @@ RUN apt-get update -y \
  && rm -r ./aws awscliv2.zip \
  && curl -sL https://aka.ms/InstallAzureCLIDeb | bash
 
+# Select the layer to provide the final container image from
+FROM ${FINAL_CONTAINER}
+LABEL maintainer="[email protected]"
+WORKDIR /root/app
 ENTRYPOINT []