clean up closed PRs in a Jenkins multibranch pipeline environment. Enable as a CRON job

cleanup_closed_PRs.sh

#!/usr/bin/env bash
#set -x
GITHUB_ACCESS_TOKEN=TOKEN_GOES_HERE
GITHUB_USERNAME=USERNAME_GOES_HERE
GITHUB_ORGANIZATION=com.example
GITHUB_REPOSITORY=microservice
## Jenkins project name
PROJECT="com.example.microservice"

function clean_closed_prs {
	local PAGE;
	local CURRENT_RESPONSE_SIZE;
	PAGE_SIZE=100;
	PAGE=1
	CURRENT_RESPONSE_SIZE=${PAGE_SIZE};
	
	RESPONSE=""
		
	while [[ ${CURRENT_RESPONSE_SIZE} -eq ${PAGE_SIZE} ]]; do
		echo >&2 "requesting page: ${PAGE}" 
		CURRENT_RESPONSE=$(curl -vs -u ${GITHUB_USERNAME}:${GITHUB_ACCESS_TOKEN} "https://api.github.com/repos/${GITHUB_ORGANIZATION}/${GITHUB_REPOSITORY}/pulls?state=closed&page=${PAGE}&per_page=${PAGE_SIZE}" 2>/dev/null | jq -r '.[] .url' | cut -d '/' -f 8)
		CURRENT_RESPONSE_SIZE=$(echo -e "${CURRENT_RESPONSE}" | wc -l)
		echo >&2 "Response size: ${CURRENT_RESPONSE_SIZE}"
		PAGE=$(($PAGE+1))
		RESPONSE=$(echo -e "${RESPONSE}\n${CURRENT_RESPONSE}")
		
		for CLOSED_PR in ${RESPONSE}; do
			if [ -z "${CLOSED_PR}" ]; then
				continue;
			fi
			CLEAN_DIR_CMD="rm -rf /var/lib/jenkins/workspace/${PROJECT}-${CLOSED_PR}*"
			$($CLEAN_DIR_CMD)
		done
	done;
}

clean_closed_prs