#!/bin/bash

set -ex

# This script should be run at the root of the repository.

# This script is used to update googleapis_commitish, gapic_generator_version,

# and libraries_bom_version in generation configuration at the time of running

# and create a pull request.

# The following commands need to be installed before running the script:

# 1. git

# 2. gh

# 3. jq

# Utility functions

# Get the latest released version of a Maven artifact.

function get_latest_released_version() {

local group_id=$1

local artifact_id=$2

group_id_url_path="$(sed 's|\.|/|g' <<< "${group_id}")"

url="https://repo1.maven.org/maven2/${group_id_url_path}/${artifact_id}/maven-metadata.xml"

xml_content=$(curl -s --fail "${url}")

# 1. Extract all version tags

# 2. Strip the XML tags to leave just the version numbers

# 3. Filter for strictly numbers.numbers.numbers (e.g., 2.54.0)

# 4. Sort by version (V) and take the last one (tail -n 1)

latest=$(echo "${xml_content}" \

| grep -oE '<version>[0-9]+\.[0-9]+\.[0-9]+</version>' \

| sed -E 's/<[^>]+>//g' \

| sort -V \

| tail -n 1)

if [[ -z "${latest}" ]]; then

echo "The latest version of ${group_id}:${artifact_id} is empty."

echo "The returned json from maven.org is invalid: ${json_content}"

exit 1

else

echo "${latest}"

fi

}

# Update a key to a new value in the generation config.

function update_config() {

local key_word=$1

local new_value=$2

local file=$3

echo "Update ${key_word} to ${new_value} in ${file}"

sed -i -e "s/^${key_word}.*$/${key_word}: ${new_value}/" "${file}"

}

# Update an action to a new version in GitHub action.

# the second argument must have the git tag (including "v").

function update_action() {

local key_word=$1

local new_value=$2

local file=$3

echo "Update ${key_word} to ${new_value} in ${file}"

# use a different delimiter because the key_word contains "/".

sed -i -e "s|${key_word}@[^ ]*$|${key_word}@${new_value}|" "${file}"

}

# The parameters of this script is:

# 1. base_branch, the base branch of the result pull request.

# 2. repo, organization/repo-name, e.g., googleapis/google-cloud-java

# 3. [optional] generation_config, the path to the generation configuration,

# the default value is generation_config.yaml in the repository root.

# 4. [optional] workflow, the library generation workflow file,

# the default value is .github/workflows/hermetic_library_generation.yaml.

while [[ $# -gt 0 ]]; do

key="$1"

case "${key}" in

--base_branch)

base_branch="$2"

shift

;;

--repo)

repo="$2"

shift

;;

--generation_config)

generation_config="$2"

shift

;;

--workflow)

workflow="$2"

shift

;;

*)

echo "Invalid option: [$1]"

exit 1

;;

esac

shift

done

if [ -z "${base_branch}" ]; then

echo "missing required argument --base_branch"

exit 1

fi

if [ -z "${repo}" ]; then

echo "missing required argument --repo"

exit 1

fi

if [ -z "${generation_config}" ]; then

generation_config="generation_config.yaml"

echo "Use default generation config: ${generation_config}"

fi

if [ -z "${workflow}" ]; then

workflow=".github/workflows/hermetic_library_generation.yaml"

echo "Use default library generation workflow file: ${workflow}"

fi

current_branch="generate-libraries-${base_branch}"

title="chore: Update generation configuration at $(date)"

git checkout "${base_branch}"

# Try to find a open pull request associated with the branch

pr_num=$(gh pr list -s open -H "${current_branch}" -q . --json number | jq ".[] | .number")

# Create a branch if there's no open pull request associated with the

# branch; otherwise checkout the pull request.

if [ -z "${pr_num}" ]; then

git checkout -b "${current_branch}"

# Push the current branch to remote so that we can

# compare the commits later.

git push -u origin "${current_branch}"

else

gh pr checkout "${pr_num}"

fi

# Only allow fast-forward merging; exit with non-zero result if there's merging

# conflict.

git merge -m "chore: merge ${base_branch} into ${current_branch}" "${base_branch}"

mkdir tmp-googleapis

# Use partial clone because only commit history is needed.

git clone --filter=blob:none https://github.com/googleapis/googleapis.git tmp-googleapis

pushd tmp-googleapis

git pull

latest_commit=$(git rev-parse HEAD)

popd

rm -rf tmp-googleapis

update_config "googleapis_commitish" "${latest_commit}" "${generation_config}"

# Update gapic-generator-java version to the latest

latest_gapic_generator_version=$(get_latest_released_version "com.google.api" "gapic-generator-java")

update_config "gapic_generator_version" "${latest_gapic_generator_version}" "${generation_config}"

# Update the GitHub Actions reference to the latest.

# After the google-cloud-java monorepo migration of sdk-platform-java,

# we cannot rely on the gapic-generator-java version tag. Let's use

# the gapic-libraries-bom version

latest_gapic_libraries_bom_version=$(get_latest_released_version "com.google.cloud" "gapic-libraries-bom")

update_action "googleapis/google-cloud-java/sdk-platform-java/.github/scripts" \

"v${latest_gapic_libraries_bom_version}" \

"${workflow}"

# Update libraries-bom version to the latest

latest_version=$(get_latest_released_version "com.google.cloud" "libraries-bom")

update_config "libraries_bom_version" "${latest_version}" "${generation_config}"

git add "${generation_config}" "${workflow}"

changed_files=$(git diff --cached --name-only)

if [[ "${changed_files}" == "" ]]; then

echo "The latest generation config is not changed."

echo "Skip committing to the pull request."

else

git commit -m "${title}"

fi

# There are potentially at most two commits: merge commit and change commit.

# We want to exit the script if no commit happens (otherwise this will be an

# infinite loop).

# `git cherry` is a way to find whether the local branch has commits that are

# not in the remote branch.

# If we find any such commit, push them to remote branch.

unpushed_commit=$(git cherry -v "origin/${current_branch}" | wc -l)

if [[ "${unpushed_commit}" -eq 0 ]]; then

echo "No unpushed commits, exit"

exit 0

fi

if [ -z "${pr_num}" ]; then

git remote add remote_repo https://cloud-java-bot:"${GH_TOKEN}@github.com/${repo}.git"

git fetch -q remote_repo

git push -f remote_repo "${current_branch}"

gh pr create --title "${title}" --head "${current_branch}" --body "${title}" --base "${base_branch}"

else

git push

gh pr edit "${pr_num}" --title "${title}" --body "${title}"

fi