add release script

Author: roycaihw

scripts/release.sh

@@ -1,10 +1,73 @@
-# This file is intended to document release steps.
-# Verify each step's result before calling the next command.
-# It is documented here with the intention of being automated
-# as a shell script later.
+#!/bin/bash
 
-echo 'git clean -xdf'
-echo 'python setup.py sdist'
-echo 'python setup.py bdist_wheel --universal'
-echo 'twine upload dist/* -r https://upload.pypi.org/legacy/ -u kubernetes'
+# Copyright 2021 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.
 
+# Workflow
+# 1. [master branch] update existing snapshot (include API change for a new alpha/beta/GA
+# release)
+#   - add a new snapshot or reuse the existing snapshot, the latter means either
+#     API change happened in a k8s patch release, or we want to include some new
+#     python / python-base change in the release note
+#   - API change w/ release notes
+#   - master change w/ release notes
+#   - submodule change w/ release notes
+# 2. [master branch] create new snapshot (include API change for a new alpha release)
+#   - add a new snapshot or reuse the existing snapshot, the latter means either
+#     API change happened in a k8s patch release, or we want to include some new
+#     python / python-base change in the release note
+#   - API change w/ release notes
+#   - master change w/ release notes
+#   - submodule change w/ release notes
+# 3. [release branch] create a new release
+#   - pull master
+#     - it's possible that master has new changes after the latest snaphost,
+#       update CHANGELOG accordingly
+#   - for generated file, resolve conflict by committing the master version
+#   - abort if a snapshot doesn't exists
+#   - generate client change, abort if API change is detected
+#   - CHANGELOG: latest snapshot becomes the release
+#   - README: add the release to README
+#   - an extra PR to update CHANGELOG and README in master
+#
+# Difference between 1&2: API change release notes
+#
+# TODO:
+# - additionally, validate the branch
+# - send the PR(s) automatically
+#
+# Usage:
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+repo_root="$(git rev-parse --show-toplevel)"
+declare -r repo_root
+cd "${repo_root}"
+
+source scripts/util/changelog.sh
+
+# KUBERNETES_BRANCH=${KUBERNETES_BRANCH:-$(python "${SCRIPT_ROOT}/constants.py" KUBERNETES_BRANCH)}
+# CLIENT_VERSION=${CLIENT_VERSION:-$(python "${SCRIPT_ROOT}/constants.py" CLIENT_VERSION)}
+# DEVELOPMENT_STATUS=${DEVELOPMENT_STATUS:-$(python "${SCRIPT_ROOT}/constants.py" DEVELOPMENT_STATUS)}
+KUBERNETES_BRANCH="release-1.18"
+CLIENT_VERSION="18.0.0-snapshot"
+DEVELOPMENT_STATUS="3 - Alpha"
+
+# validate inputs
+
+# get Kubernetes API Version
+old_api_version="1.17.13"
+new_api_version=""