koha-backup-db-only

#!/bin/bash

set -euo pipefail

# Script version
VERSION="0.1.0"
# Set the name of the script to variable
SCRIPT_NAME="$(basename "${0}")"

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
NC='\033[0m' # No Color

# Functions
# Help function
function help_message() {
  cat <<EOF
Usage: ${SCRIPT_NAME} -i <instance_id> [-d <dump_directory>] [-h] [-v]

Options:
  -i: The name of the koha instance. Can be specified multiple times.
  -d: The path of the dump directory. If not specified, a temporary directory will be used.
  -h: Print help message.
  -v: Print version.

Examples:
  ${SCRIPT_NAME} -i library
  ${SCRIPT_NAME} -i library1 -i library2 -d /path/to/dump/directory
EOF
}

# Check if required packages are installed
check_requirements() {
  local packages=(xmlstarlet mysqldump)

  for package in "${packages[@]}"; do
    if ! command -v "$package" &> /dev/null; then
      echo -e "${RED}Error: $package is not installed.${NC}" >&2
      exit 1
    fi
  done
}

# Parse command-line options
instance_ids=()
while [[ $# -gt 0 ]]; do
  case $1 in
    -i)
      if [[ -z ${2:-} ]]; then
        echo -e "${RED}Error: instance id is missing.${NC}" >&2
        help_message >&2
        exit 1
      fi
      instance_ids+=("$2")
      shift
      ;;
    -d)
      if [[ -z ${2:-} ]]; then
        echo -e "${RED}Error: dump directory path is missing.${NC}" >&2
        help_message >&2
        exit 1
      fi
      DUMP_DIR="$2"
      shift
      ;;
    -v|--version)
      echo "${SCRIPT_NAME} version ${VERSION}"
      exit 0
      ;;
    -h|--help)
      help_message
      exit 0
      ;;
    *)
      echo "Error: Unknown option: $1" >&2
      help_message >&2
      exit 1
      ;;
  esac
  shift
done

# Check if instance_ids are set
if [[ ${#instance_ids[@]} -eq 0 ]]; then
  echo -e "${RED}Error: you must specify at least one instance id.${NC}" >&2
  help_message >&2
  exit 1
fi

# Check if required packages are installed
check_requirements

# Set up temporary directory for SQL dump if not specified
if [[ -z ${DUMP_DIR+x} ]]; then
  DUMP_DIR=$(mktemp -d)
fi

# Function to dump database
dump_db() {
  local instance_name=$1

  # Set the path to koha_conf.xml
  koha_conf="/etc/koha/sites/${instance_name}/koha-conf.xml"

  # Retrieve the Koha user, password, and database hostname
  kohadbpwd=$(sudo xmlstarlet sel -t -v 'yazgfs/config/pass' "$koha_conf")
  kohadbuser="koha_${instance_name}"
  kohadbhost=$(sudo xmlstarlet sel -t -v 'yazgfs/config/hostname' "$koha_conf")
  date=$(date +"%m-%d-%Y-%Hh%M")

# Dump Koha database
# See:
# https://stackoverflow.com/questions/52423595/mysqldump-couldnt-execute-unknown-table-column-statistics-in-information-sc
# https://bugs.mysql.com/bug.php?id=109685#c530123
# https://repost.aws/knowledge-center/mysqldump-error-rds-mysql-mariadb
# https://snapshooter.com/docs/fixing-mysqldump-couldn-t-execute-flush-tables-access-denied
# mysqldump $dbflag --no-tablespaces --host="$mysqlhost" --single-transaction --user="$mysqluser" --password="$mysqlpass" "$mysqldb" | gzip >"$dbdump"
mysqldump -h "$kohadbhost" -u "$kohadbuser" -p"$kohadbpwd"  --databases --no-tablespaces --set-gtid-purged=OFF --column-statistics=0 "koha_${instance_name}" > "${DUMP_DIR}/koha_${instance_name}-$date.sql"
}

# Lock file to prevent concurrent execution
LOCK_FILE="/tmp/${SCRIPT_NAME}.lock"
(
flock -n 200 || {
echo "Script is already running"
exit 1
}

# Dump Koha instances
for instance_name in "${instance_ids[@]}"; do
dump_db "$instance_name"
echo "The database for $instance_name has been saved to ${DUMP_DIR}/koha_${instance_name}-$date.sql"
done
) 200>"$LOCK_FILE"