generate-crds.sh

#!/usr/bin/env bash
#
# Copyright 2021 SAP SE or an SAP affiliate company. All rights reserved. This file is licensed under the Apache Software License, v. 2 except as noted otherwise in the LICENSE file
#
# 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

# Usage:
# generate-crds.sh [<flags>] <group> [<group> ...]
#     Generate manifests for all CRDs to the current working directory.
#     Useful for development purposes.
#
#     -p <file-name-prefix>               File name prefix for manifest files (e.g. '10-crd-')
#     -l (Optional)                       If this argument is given then the generated CRDs will have label gardener.cloud/deletion-protected: "true"
#     -k (Optional)                       If this argument is given then the generated CRDs will have annotation resources.gardener.cloud/keep-object: "true"
#     -r <reason> (Optional)              If this argument is given then the generated CRDs will have annotation api-approved.kubernetes.io: "<reason>"
#     --allow-dangerous-types (Optional)  If this argument is given then the CRD generation will tolerate issues related to dangerous types.
#     <group>                             List of groups to generate (generate all if unset)

if ! command -v controller-gen &> /dev/null ; then
  >&2 echo "controller-gen not available"
  exit 1
fi

output_dir="$(pwd)"
output_dir_temp="$(mktemp -d)"
add_deletion_protection_label=false
add_keep_object_annotation=false
k8s_io_api_approval_reason="unapproved, temporarily squatting"
crd_options=""

# setup virtual GOPATH
source $(dirname $0)/vgopath-setup.sh

export GO111MODULE=off

get_group_package () {
  case "$1" in
  "extensions.gardener.cloud")
    echo "github.com/gardener/gardener/pkg/apis/extensions/v1alpha1"
    ;;
  "resources.gardener.cloud")
    echo "github.com/gardener/gardener/pkg/apis/resources/v1alpha1"
    ;;
  "operator.gardener.cloud")
    echo "github.com/gardener/gardener/pkg/apis/operator/v1alpha1"
    ;;
  "druid.gardener.cloud")
    echo "github.com/gardener/etcd-druid/api/v1alpha1"
    ;;
  "hvpaautoscaling.k8s.io")
    echo "github.com/gardener/hvpa-controller/api/v1alpha1"
    ;;
  "fluentbit.fluent.io")
    echo "github.com/fluent/fluent-operator/v2/apis/fluentbit/v1alpha2"
    ;;
  "autoscaling.k8s.io")
    echo "k8s.io/autoscaler/vertical-pod-autoscaler/pkg/apis/autoscaling.k8s.io/v1"
    ;;
  "machine.sapcloud.io")
    echo "github.com/gardener/machine-controller-manager/pkg/apis/machine/v1alpha1"
    ;;
  *)
    >&2 echo "unknown group $1"
    return 1
  esac
}

generate_all_groups () {
  generate_group extensions.gardener.cloud
  generate_group resources.gardener.cloud
  generate_group operator.gardener.cloud
  generate_group druid.gardener.cloud
  generate_group hvpaautoscaling.k8s.io
  generate_group autoscaling.k8s.io
  generate_group fluentbit.fluent.io
  generate_group machine.sapcloud.io
}

generate_group () {
  local group="$1"
  echo "Generating CRDs for $group group"

  local package="$(get_group_package "$group")"
  if [ -z "$package" ] ; then
    exit 1
  fi
  local package_path="$(go list -f '{{ .Dir }}' "$package")"
  if [ -z "$package_path" ] ; then
    exit 1
  fi

  generate="controller-gen crd"$crd_options" paths="$package_path" output:crd:dir="$output_dir_temp" output:stdout"

  if [[ "$group" == "druid.gardener.cloud" ]]; then
    # /scale subresource is intentionally removed from this CRD, although it is specified in the original CRD from
    # etcd-druid, due to adverse interaction with VPA.
    # See https://github.com/gardener/gardener/pull/6850 and https://github.com/gardener/gardener/pull/8560#discussion_r1347470394
    # TODO(shreyas-s-rao): Remove this workaround as soon as the scale subresource is supported properly.
    etcd_druid_dir="$(go list -f '{{ .Dir }}' "github.com/gardener/etcd-druid")"
    etcd_api_types_file="${etcd_druid_dir}/api/v1alpha1/types_etcd.go"
    # Create a local copy outside the mod cache path in order to patch the types file via sed.
    etcd_api_types_backup="$(mktemp -d)/types_etcd.go"
    cp "$etcd_api_types_file" "$etcd_api_types_backup"
    chmod +w "$etcd_api_types_file" "$etcd_druid_dir/api/v1alpha1/"
    trap 'cp "$etcd_api_types_backup" "$etcd_api_types_file" && chmod -w "$etcd_druid_dir/api/v1alpha1/"' EXIT
    sed -i '/\/\/ +kubebuilder:subresource:scale:specpath=.spec.replicas,statuspath=.status.replicas,selectorpath=.status.labelSelector/d' "$etcd_api_types_file"
    $generate
  elif [[ "$group" == "autoscaling.k8s.io" ]]; then
    # See https://github.com/kubernetes/autoscaler/blame/master/vertical-pod-autoscaler/hack/generate-crd-yaml.sh#L43-L45
    generator_output="$(mktemp -d)/controller-gen.log"
    # As go list does not work with symlinks we need to manually construct the package paths to correctly
    # generate v1beta2 CRDs.
    package_path="${package_path};${package_path}beta2;"
    generate="controller-gen crd"$crd_options" paths="$package_path" output:crd:dir="$output_dir_temp" output:stdout"
    $generate &> "$generator_output" ||:
    grep -v -e 'map keys must be strings, not int' -e 'not all generators ran successfully' -e 'usage' "$generator_output" && { echo "Failed to generate CRD YAMLs."; exit 1; }
  else
    $generate
  fi

  local relevant_files=("$@")
  while IFS= read -r crd; do
    crd_out="$output_dir/$file_name_prefix$(basename $crd)"
    mv "$crd" "$crd_out"
    relevant_files+=("$(basename "$crd_out")")

    if $add_deletion_protection_label; then
      if grep -q "clusters.extensions.gardener.cloud"  "$crd_out"; then
        :
      else
        sed -i '4 a\  labels:\n\    gardener.cloud/deletion-protected: "true"' "$crd_out"
      fi
    fi

    if $add_keep_object_annotation; then
      sed -i '/^  annotations:.*/a\    resources.gardener.cloud/keep-object: "true"' "$crd_out"
    fi

    # TODO(plkokanov): this is needed to add the `api-approved.kubernetes.io` annotaiton to resource from the *.k8s.io api group generated by controller-gen
    # Currently there is an issue open to do that automatically: https://github.com/kubernetes-sigs/controller-tools/issues/656
    if [[ ${group} =~ .*\.k8s\.io ]]; then
      sed -i "/^  annotations:.*/a\    api-approved.kubernetes.io: $k8s_io_api_approval_reason" "$crd_out"
    fi
  done < <(ls "$output_dir_temp/${group/hvpa/}"_*.yaml)

  # garbage collection - clean all generated files for this group to account for changed prefix or removed resources
  local pattern=".*${group}_.*\.yaml"
  if [[ "$group" == "autoscaling.k8s.io" ]]; then
    pattern=".*${group}_v.*\.yaml"
  fi

  while IFS= read -r file; do
    file_name=$(basename "$file")
    delete_no_longer_needed_file=true

    for relevant_file_name in "${relevant_files[@]}"; do
      if [[ $file_name == "$relevant_file_name" ]] || [[ ! $file_name =~ $pattern ]]; then
        delete_no_longer_needed_file=false
        break
      fi
    done

    if $delete_no_longer_needed_file; then
      rm "$file"
    fi
  done < <(ls "$output_dir")
}

parse_flags() {
  while test $# -gt 0; do
    case "$1" in
    -p)
      file_name_prefix="$2"
      shift
      shift
      ;;
    -r)
      k8s_io_api_approval_reason="$2"
      shift
      shift
      ;;
    -l)
      add_deletion_protection_label=true
      shift
      ;;
    -k)
      add_keep_object_annotation=true
      shift
      ;;
    --allow-dangerous-types)
      crd_options=":allowDangerousTypes=true"
      shift
      ;;
    *)
      args+=("$1")
      shift
      ;;
    esac
  done
}

parse_flags "$@"

if [ -n "$args" ]; then
  for group in "${args[@]}"; do
    generate_group "$group"
  done
else
  generate_all_groups
fi