Multi-Arch Docker Image Releases (kudobuilder#214)

Co-authored-by: Marcin Owsiany <mowsiany@D2iQ.com>
Signed-off-by: Ken Sipe <kensipe@gmail.com>

Author: kensipe

DOCKER.md

@@ -0,0 +1,27 @@
+# Docker Releases
+
+There is strong interest in the community to support a number of architectures with docker images.  One driver is [Operator SDK scorecard](https://sdk.operatorframework.io/docs/advanced-topics/scorecard/scorecard/) for which KUTTL provides additional test features.   The following architectures are needed to support scorecard:
+
+* linux/amd64
+* linux/arm64
+* linux/ppc64le
+* linux/s390x
+
+In order to support this, we are using the new and experimental docker [buildx](https://docs.docker.com/engine/reference/commandline/buildx/).  This allows for building and pushing of several architectures to the same docker repository allowing for the client platform to determine preferred architecture for its pull request. 
+
+In addition to using `buildx` there are two more requirements to make this work:
+
+1. The base image must support all the architectures desired.  For this reason we now use `registry.access.redhat.com/ubi8/ubi-minimal`.
+1. The go libraries must support the architectures.
+
+## Building and Pushing Multi-Arch Docker Image
+
+For a detailed understanding, please read the [buildx build documentation](https://docs.docker.com/engine/reference/commandline/buildx_build/).
+You will need to `enable` docker CLI experimental features for this to work.
+
+To build and push manually the following is necessary:  `make docker-release`
+
+This will result in a command similar to the following with the version tag replaced with the current version:
+`docker buildx build . -t kudobuilder/kuttl:v0.6.1  --platform linux/amd64,linux/arm64,linux/ppc64le --push`
+
+Updates for platform builds are maintained in [hack/docker-release.sh](hack/docker-release.sh).

Dockerfile

@@ -25,14 +25,15 @@ RUN go get -d -v ./...
 RUN make cli
 
 # release image with kubectl + kuttl
-FROM debian:buster
+FROM registry.access.redhat.com/ubi8/ubi-minimal:latest
 
-RUN apt-get update && apt-get install -y curl wget gnupg2 apt-transport-https vim
-RUN curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | apt-key add -
+RUN microdnf install vim
+RUN echo 'alias vi=vim' >> ~/.bashrc
 
-RUN echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | tee -a /etc/apt/sources.list.d/kubernetes.list
-RUN apt-get update
-RUN  apt-get install -y kubectl
+#  kube 1.18
+RUN curl -LO https://storage.googleapis.com/kubernetes-release/release/v1.18.0/bin/linux/amd64/kubectl
+RUN chmod +x ./kubectl
+RUN mv ./kubectl /usr/local/bin/kubectl
 
 COPY --from=builder /go/src/kuttl/bin/kubectl-kuttl /usr/bin/kubectl-kuttl
 

Makefile

@@ -60,10 +60,16 @@ clean: cli-clean  ## Cleans CLI and kind logs
 	rm -rf kind-logs-*
 
 .PHONY: docker
-# build docker image
-docker:  ## Builds docker image
+# build a local docker image (specific to the local platform only)
+docker:  ## Builds docker image for architecture of the local env
 	docker build . -t kuttl
 
+.PHONY: docker-release
+# build and push a multi-arch docker image
+docker-release:  ## Build and push multi-arch docker images
+	./hack/docker-release.sh
+
+
 # Install CLI
 cli-install:  ## Installs kubectl-kuttl to GOBIN
 	go install -ldflags "${LDFLAGS}" ./cmd/kubectl-kuttl

RELEASE.md

@@ -71,6 +71,9 @@ The release process is:
 It is possible outside of the standard release process to build a "snapshot" release using the following command: `goreleaser release --skip-publish --snapshot --rm-dist`
 This process will create a `dist` folder with all the build artifacts. The changelog is not created unless a full release is executed. If you are looking to get a "similar" changelog, install [github-release-notes](https://github.com/buchanae/github-release-notes) and execute `github-release-notes -org kudobuilder -repo kuttl -since-latest-release`.
 
+### Docker Release
+
+The docker release is accomplished by `make docker-release`.  Details on what is required are provided in [Docker.md](DOCKER.md).
 
 ### Cutting a Release Branch
 

hack/docker-release.sh

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+
+#####
+#  Used to produce a multi-arch docker image and push it onto docker hub
+#  This requires the use of the buildx experimental feature in the later version of docker
+#####
+
+set -o nounset
+set -o pipefail
+# intentionally not setting 'set -o errexit' because we want to print custom error messages
+
+GIT_VERSION="$(git describe --abbrev=0 --tags | cut -b 2-)"
+
+echo "Releasing for version: $GIT_VERSION"
+
+# run buildx ls to check that buildx is possible on this platform
+docker buildx ls > /dev/null 2>&1
+RETVAL=$?
+if [[ ${RETVAL} != 0 ]]; then
+    echo "Invoking 'docker buildx ls' ends with non-zero exit code. (✖╭╮✖)"
+    echo "Updated docker with experimental options enabled is required."
+    exit 1
+fi
+
+docker buildx build . -t "kudobuilder/kuttl:v$GIT_VERSION"  --platform linux/amd64,linux/arm64,linux/ppc64le --push
+
+RETVAL=$?
+if [[ ${RETVAL} != 0 ]]; then
+    echo "Invoking 'docker buildx build' ends with non-zero exit code. （╯°□°）╯ ┻━┻"
+    exit 1
+fi
+
+echo "docker build and push was successful! ヽ(•‿•)ノ"