chore: create script to update golang

Author: justinsb

dev/codebots/update-golang-version

@@ -0,0 +1,58 @@
+#!/bin/bash
+
+# Copyright 2022 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.
+
+
+# Helper script to update golang to latest version
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+REPO_ROOT=$(git rev-parse --show-toplevel)
+cd ${REPO_ROOT}
+
+# TODO: Should we update to the latest go, or the latest go in a particular minor?
+GO_TOOLCHAIN=$(curl https://go.dev/dl/?mode=json | jq -r '[.[] | select(.stable == true)] | .[0].version')
+echo "GO_TOOLCHAIN=$GO_TOOLCHAIN"
+
+git switch --force-create codebot-update-golang-version-${GO_TOOLCHAIN}
+
+# GO_VERSION is the GO_TOOLCHAIN without the go prefix
+GO_VERSION=${GO_TOOLCHAIN#go}
+echo "GO_VERSION=$GO_VERSION"
+
+# Update go.mod files
+# Tidy each individual go.mod
+for gomod_file in $(find "${REPO_ROOT}" -name "go.mod"); do
+    dir=$(dirname ${gomod_file})
+    cd "${dir}"
+    echo "Updating $gomod_file to toolchain $GO_TOOLCHAIN"
+    go mod edit -toolchain=${GO_TOOLCHAIN}
+done
+
+# Update Docker images
+for dockerfile in $(find "${REPO_ROOT}" -name "Dockerfile*"); do
+  echo "Updating Dockerfile $dockerfile to go image $GO_VERSION"
+  sed -i -e "s/FROM golang:[0-9.]*/FROM golang:$GO_VERSION/g" $dockerfile
+done
+
+if $(git diff --quiet); then
+  echo "No changes"
+else
+  cd ${REPO_ROOT}
+  git add .
+  git commit -m "codebot: update go to ${GO_VERSION}"
+fi