build: Refactor to use BuildKit

Signed-off-by: Chris Crone <christopher.crone@docker.com>

Dockerfile

@@ -5,7 +5,7 @@ ARG BUILD_DEBIAN_VERSION=slim-stretch
 ARG RUNTIME_ALPINE_VERSION=3.11.5
 ARG RUNTIME_DEBIAN_VERSION=stretch-20200414-slim
 
-ARG BUILD_PLATFORM=alpine
+ARG DISTRO=alpine
 
 FROM docker:${DOCKER_VERSION} AS docker-cli
 
@@ -40,15 +40,14 @@ RUN apt-get update && apt-get install --no-install-recommends -y \
     openssl \
     zlib1g-dev
 
-FROM build-${BUILD_PLATFORM} AS build
-COPY docker-compose-entrypoint.sh /usr/local/bin/
+FROM build-${DISTRO} AS build
 ENTRYPOINT ["sh", "/usr/local/bin/docker-compose-entrypoint.sh"]
-COPY --from=docker-cli /usr/local/bin/docker /usr/local/bin/docker
 WORKDIR /code/
+COPY docker-compose-entrypoint.sh /usr/local/bin/
+COPY --from=docker-cli /usr/local/bin/docker /usr/local/bin/docker
 RUN pip install \
     virtualenv==20.0.30 \
     tox==3.19.0
-
 COPY requirements-dev.txt .
 COPY requirements-indirect.txt .
 COPY requirements.txt .
@@ -64,9 +63,14 @@ ARG GIT_COMMIT=unknown
 ENV DOCKER_COMPOSE_GITSHA=$GIT_COMMIT
 RUN script/build/linux-entrypoint
 
+FROM scratch AS bin
+ARG TARGETARCH
+ARG TARGETOS
+COPY --from=build /usr/local/bin/docker-compose /docker-compose-${TARGETOS}-${TARGETARCH}
+
 FROM alpine:${RUNTIME_ALPINE_VERSION} AS runtime-alpine
 FROM debian:${RUNTIME_DEBIAN_VERSION} AS runtime-debian
-FROM runtime-${BUILD_PLATFORM} AS runtime
+FROM runtime-${DISTRO} AS runtime
 COPY docker-compose-entrypoint.sh /usr/local/bin/
 ENTRYPOINT ["sh", "/usr/local/bin/docker-compose-entrypoint.sh"]
 COPY --from=docker-cli  /usr/local/bin/docker           /usr/local/bin/docker

Jenkinsfile

@@ -13,6 +13,9 @@ pipeline {
         timeout(time: 2, unit: 'HOURS')
         timestamps()
     }
+    environment {
+        DOCKER_BUILDKIT="1"
+    }
 
     stages {
         stage('Build test images') {
@@ -69,7 +72,7 @@ def buildImage(baseImage) {
             ansiColor('xterm') {
                 sh """docker build -t ${imageName} \\
                     --target build \\
-                    --build-arg BUILD_PLATFORM="${baseImage}" \\
+                    --build-arg DISTRO="${baseImage}" \\
                     --build-arg GIT_COMMIT="${scmvar.GIT_COMMIT}" \\
                     .\\
                 """

Release.Jenkinsfile

@@ -13,6 +13,9 @@ pipeline {
         timeout(time: 2, unit: 'HOURS')
         timestamps()
     }
+    environment {
+        DOCKER_BUILDKIT="1"
+    }
 
     stages {
         stage('Build test images') {
@@ -229,7 +232,7 @@ def buildImage(baseImage) {
             ansiColor('xterm') {
                 sh """docker build -t ${imageName} \\
                     --target build \\
-                    --build-arg BUILD_PLATFORM="${baseImage}" \\
+                    --build-arg DISTRO="${baseImage}" \\
                     --build-arg GIT_COMMIT="${scmvar.GIT_COMMIT}" \\
                     .\\
                 """
@@ -276,7 +279,7 @@ def buildRuntimeImage(baseImage) {
     def imageName = "docker/compose:${baseImage}-${env.BRANCH_NAME}"
     ansiColor('xterm') {
         sh """docker build -t ${imageName} \\
-            --build-arg BUILD_PLATFORM="${baseImage}" \\
+            --build-arg DISTRO="${baseImage}" \\
             --build-arg GIT_COMMIT="${scmvar.GIT_COMMIT.take(7)}" \\
             .
         """

script/build/linux

@@ -5,14 +5,12 @@ set -ex
 ./script/clean
 
 DOCKER_COMPOSE_GITSHA="$(script/build/write-git-sha)"
-TAG="docker/compose:tmp-glibc-linux-binary-${DOCKER_COMPOSE_GITSHA}"
 
-docker build -t "${TAG}" . \
-       --build-arg BUILD_PLATFORM=debian \
-       --build-arg GIT_COMMIT="${DOCKER_COMPOSE_GITSHA}"
-TMP_CONTAINER=$(docker create "${TAG}")
-mkdir -p dist
+docker build . \
+       --target bin \
+       --build-arg DISTRO=debian \
+       --build-arg GIT_COMMIT="${DOCKER_COMPOSE_GITSHA}" \
+       --output dist/
 ARCH=$(uname -m)
-docker cp "${TMP_CONTAINER}":/usr/local/bin/docker-compose "dist/docker-compose-Linux-${ARCH}"
-docker container rm -f "${TMP_CONTAINER}"
-docker image rm -f "${TAG}"
+# Ensure that we output the binary with the same name as we did before
+mv dist/docker-compose-linux-amd64 "dist/docker-compose-Linux-${ARCH}"

script/build/test-image

@@ -13,6 +13,6 @@ IMAGE="docker/compose-tests"
 DOCKER_COMPOSE_GITSHA="$(script/build/write-git-sha)"
 docker build -t "${IMAGE}:${TAG}" . \
        --target build \
-       --build-arg BUILD_PLATFORM="debian" \
+       --build-arg DISTRO="debian" \
        --build-arg GIT_COMMIT="${DOCKER_COMPOSE_GITSHA}"
 docker tag "${IMAGE}":"${TAG}" "${IMAGE}":latest