add ability to upgrade via renovate (#11)

Signed-off-by: Anurag <[email protected]>

hack/semver-upgrade.sh

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+# Copyright 2023 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+set -x
+
+semver_upgrade() {
+IFS=. read -r version minor patch <<EOF
+$VERSION
+EOF
+
+case "$1" in
+patch) tag="$version.$minor.$((patch+1))"; ;;
+major) tag="$((version+1)).0.0"; ;;
+*)     tag="$version.$((minor+1)).0"; ;;
+esac
+
+echo $tag
+}

hack/upgrade-builder-image.sh

@@ -0,0 +1,69 @@
+#!/usr/bin/env bash
+
+# Copyright 2023 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This script is executed in the Update-Bot container.
+# It checks if the Dockerfile for the build container has changed.
+# If so, it uses the version of the main branch as the basis for creating a new image tag. 
+# The script also checks if the image tag for the build image exists in the main branch. 
+# We assume that only one branch and one PR will be created for the changes in the build container. 
+# Therefore, we can update this branch as many times as we want and reuse the next available tag after the one from the main branch.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+export BUILDER_IMAGE=ghcr.io/sovereigncloudstack/cspo-builder
+
+REPO_ROOT=$(realpath $(dirname "${BASH_SOURCE[0]}")/..)
+cd "${REPO_ROOT}" || exit 1
+
+source "${REPO_ROOT}/hack/semver-upgrade.sh"
+
+if git diff --exit-code .builder-image-version.txt images/builder/Dockerfile images/builder/build.sh > /dev/null; then
+  echo "nothing seems to have changed."
+  exit 0
+fi
+
+if [ "${CI:-false}" = true ] ; then
+  echo "$BUILD_IMAGE_TOKEN" | docker login ghcr.io -u "$BUILD_IMAGE_USER" --password-stdin
+fi
+
+VERSION=$(git fetch --quiet origin main && git show origin/main:.builder-image-version.txt)
+if [ -z "$VERSION" ]; then
+  echo "failed to find BUILDER_IMAGE_VERSION in Makefile of origin/main branch"
+  exit 1
+fi
+export VERSION
+
+NEW_VERSION=$(semver_upgrade patch "$VERSION")
+export NEW_VERSION
+
+if ! docker manifest inspect "$BUILDER_IMAGE:$VERSION" > /dev/null; then
+  echo "could not find image $BUILDER_IMAGE:$VERSION"
+  exit 1
+fi
+echo "$NEW_VERSION" > .builder-image-version.txt
+echo "Wrote new version $NEW_VERSION to .builder-image-version.txt"
+
+if docker manifest inspect ghcr.io/sovereigncloudstack/cspo-builder:${NEW_VERSION} > /dev/null ; echo $?; then
+
+  sed -i -e "/^BUILDER_IMAGE_VERSION /s/:=.*$/:= ${NEW_VERSION}/" Makefile
+  grep -r -E 'ghcr.io/sovereigncloudstack/cspo-builder:[0-9].*.*' -l | xargs sed -i -e "s/ghcr.io\/sovereigncloudstack\/cspo-builder:${VERSION}/ghcr.io\/sovereigncloudstack\/cspo-builder:${NEW_VERSION}/g"
+  docker build -t ghcr.io/sovereigncloudstack/cspo-builder:${NEW_VERSION}  ./images/builder
+  docker push ghcr.io/sovereigncloudstack/cspo-builder:${NEW_VERSION}
+else
+  exit 1
+fi