multiarch docker build

Makefile

@@ -175,3 +175,6 @@ test-docs: build-docs
 serve-docs: build-docs
 	@echo Stating docs website on http://localhost:${DOCS_PORT}/_build/html/index.html
 	@docker run -i -p ${DOCS_PORT}:8000 -e USER_ID=$$UID flux-docs
+
+build/image/multiarch:
+	docker buildx build --platform linux/amd64,linux/arm64,linux/arm/v7 -t zlangbert/flux:latest-multiarch -f docker/Dockerfile.build . --push

docker/Dockerfile.build

@@ -0,0 +1,74 @@
+# builder image
+#
+FROM --platform=$BUILDPLATFORM golang:1.13.5-buster as builder
+
+ARG BUILDPLATFORM
+ARG TARGETPLATFORM
+ARG TARGETARCH
+RUN echo "I am running on $BUILDPLATFORM, building for $TARGETPLATFORM"
+
+WORKDIR /workspace
+COPY . .
+
+RUN make ARCH=$TARGETARCH build/kubectl build/fluxd
+
+# build final image
+#
+FROM alpine:3.10
+
+WORKDIR /home/flux
+
+RUN apk add --no-cache openssh-client ca-certificates tini 'git>=2.12.0' 'gnutls>=3.6.7' gnupg gawk socat
+RUN apk add --no-cache -X http://dl-cdn.alpinelinux.org/alpine/edge/testing git-secret
+
+# Add git hosts to known hosts file so we can use
+# StrickHostKeyChecking with git+ssh
+ADD ./docker/known_hosts.sh /home/flux/known_hosts.sh
+RUN sh /home/flux/known_hosts.sh /etc/ssh/ssh_known_hosts && \
+    rm /home/flux/known_hosts.sh
+
+# Add default SSH config, which points at the private key we'll mount
+COPY ./docker/ssh_config /etc/ssh/ssh_config
+
+COPY --from=builder /workspace/build/fluxd /usr/local/bin/
+COPY ./docker/kubeconfig /root/.kube/config
+COPY --from=builder /workspace/build/kubectl /usr/local/bin/
+
+# These are pretty static
+LABEL maintainer="Flux CD <https://github.com/fluxcd/flux/issues>" \
+      org.opencontainers.image.title="flux" \
+      org.opencontainers.image.description="The GitOps operator for Kubernetes" \
+      org.opencontainers.image.url="https://github.com/fluxcd/flux" \
+      org.opencontainers.image.source="[email protected]:fluxcd/flux" \
+      org.opencontainers.image.vendor="Flux CD" \
+      org.label-schema.schema-version="1.0" \
+      org.label-schema.name="flux" \
+      org.label-schema.description="The GitOps operator for Kubernetes" \
+      org.label-schema.url="https://github.com/fluxcd/flux" \
+      org.label-schema.vcs-url="[email protected]:fluxcd/flux" \
+      org.label-schema.vendor="Flux CD"
+
+ENTRYPOINT [ "/sbin/tini", "--", "fluxd" ]
+
+# Get the kubeyaml binary (files) and put them on the path
+COPY --from=quay.io/squaremo/kubeyaml:0.7.0 /usr/lib/kubeyaml /usr/lib/kubeyaml/
+ENV PATH=/bin:/usr/bin:/usr/local/bin:/usr/lib/kubeyaml
+
+# Create minimal nsswitch.conf file to prioritize the usage of /etc/hosts over DNS queries.
+# This resolves the conflict between:
+# * fluxd using netgo for static compilation. netgo reads nsswitch.conf to mimic glibc,
+#   defaulting to prioritize DNS queries over /etc/hosts if nsswitch.conf is missing:
+#   https://github.com/golang/go/issues/22846
+# * Alpine not including a nsswitch.conf file. Since Alpine doesn't use glibc
+#   (it uses musl), maintainers argue that the need of nsswitch.conf is a Go bug:
+#   https://github.com/gliderlabs/docker-alpine/issues/367#issuecomment-354316460
+RUN [ ! -e /etc/nsswitch.conf ] && echo 'hosts: files dns' > /etc/nsswitch.conf
+
+ARG BUILD_DATE
+ARG VCS_REF
+
+# These will change for every build
+LABEL org.opencontainers.image.revision="$VCS_REF" \
+      org.opencontainers.image.created="$BUILD_DATE" \
+      org.label-schema.vcs-ref="$VCS_REF" \
+      org.label-schema.build-date="$BUILD_DATE"