docker-entrypoint.sh

#!/bin/sh

set -eu

: "${DEBUG:=0}"

if [ "${DEBUG}" -eq 1 ]; then
    set -x
fi

##### Function definitions ####

deriveMySQLSettingsFromExistingConfigFile() {
  if [ ! -f /etc/pdns/pdns.conf ]; then
    echo "Use of existing file /etc/pdns/pdns.conf requested but file does not exist!"
    exit 1
  fi

  PDNS_gmysql_host=$(sed -n 's/^gmysql-host=\(.*\)/\1/p' < /etc/pdns/pdns.conf)
  PDNS_gmysql_port=$(sed -n 's/^gmysql-port=\(.*\)/\1/p' < /etc/pdns/pdns.conf)
  PDNS_gmysql_user=$(sed -n 's/^gmysql-user=\(.*\)/\1/p' < /etc/pdns/pdns.conf)
  PDNS_gmysql_password=$(sed -n 's/^gmysql-password=\(.*\)/\1/p' < /etc/pdns/pdns.conf)
  PDNS_gmysql_dbname=$(sed -n 's/^gmysql-dbname=\(.*\)/\1/p' < /etc/pdns/pdns.conf)
}

deriveMySQLSettingsFromEnvironment() {
  # Configure mysql env vars
  : "${PDNS_gmysql_host:=${MYSQL_ENV_MYSQL_HOST:-mysql}}"
  : "${PDNS_gmysql_port:=${MYSQL_ENV_MYSQL_PORT:-3306}}"
  : "${PDNS_gmysql_user:=${MYSQL_ENV_MYSQL_USER:-root}}"
  if [ "${PDNS_gmysql_user}" = 'root' ]; then
      : "${PDNS_gmysql_password:=${MYSQL_ENV_MYSQL_ROOT_PASSWORD:-}}"
  fi
  : "${PDNS_gmysql_password:=${MYSQL_ENV_MYSQL_PASSWORD:-powerdns}}"
  : "${PDNS_gmysql_dbname:=${MYSQL_ENV_MYSQL_DATABASE:-powerdns}}"

  # Use first part of node name as database name suffix
  if [ "${NODE_NAME:-}" ]; then
      NODE_NAME=$(echo "${NODE_NAME}" | sed -e 's/\..*//' -e 's/-//')
      PDNS_gmysql_dbname="${PDNS_gmysql_dbname}${NODE_NAME}"
  fi

  export PDNS_gmysql_host PDNS_gmysql_port PDNS_gmysql_user PDNS_gmysql_password PDNS_gmysql_dbname
}

generateMySQLCommand() {
  : "${MYSQL_CLIENT_EXTRA_PARAMS:=}"

  # Password Auth
  if [ "${PDNS_gmysql_password:-}" ]; then
      MYSQL_CLIENT_EXTRA_PARAMS="${MYSQL_CLIENT_EXTRA_PARAMS} -p${PDNS_gmysql_password}"
  fi

  # Allow socket connections
  if [ "${PDNS_gmysql_socket:-}" ]; then
      export PDNS_gmysql_host='localhost'
      MYSQL_CLIENT_EXTRA_PARAMS="${MYSQL_CLIENT_EXTRA_PARAMS} --socket=${PDNS_gmysql_socket}"
  fi

  MYSQL_COMMAND="mariadb -h ${PDNS_gmysql_host} -P ${PDNS_gmysql_port} -u ${PDNS_gmysql_user} ${MYSQL_CLIENT_EXTRA_PARAMS}"
}

createDatabaseIfRequested() {
  # Initialize DB if needed
  if [ "${SKIP_DB_CREATE:-false}" != 'true' ]; then
      $MYSQL_COMMAND -e "CREATE DATABASE IF NOT EXISTS ${PDNS_gmysql_dbname}"
  fi
}

initDatabase() {
  if [ "${SKIP_DB_INIT:-false}" != 'true'  ]; then
    MYSQL_CHECK_IF_HAS_TABLE="SELECT COUNT(DISTINCT table_name) FROM information_schema.columns WHERE table_schema = '${PDNS_gmysql_dbname}';"
    MYSQL_NUM_TABLE=$($MYSQL_COMMAND --batch --skip-column-names -e "$MYSQL_CHECK_IF_HAS_TABLE")
    if [ "$MYSQL_NUM_TABLE" -eq 0 ]; then
      echo "Database exists and has no tables yet, doing init";
      $MYSQL_COMMAND -D "$PDNS_gmysql_dbname" < /usr/share/doc/pdns/schema.mysql.sql
    else
      echo "Database exists but already has tables, will not try to init";
    fi
  fi
}

migrateDatabaseTo47() {
  # SQL migration to version 4.7
  MYSQL_CHECK_IF_47="SELECT COUNT(*) FROM information_schema.columns WHERE table_schema = '${PDNS_gmysql_dbname}' AND table_name = 'domains' AND column_name = 'options';"
  MYSQL_NUM_TABLE=$($MYSQL_COMMAND --batch --skip-column-names -e "$MYSQL_CHECK_IF_47")
  if [ "$MYSQL_NUM_TABLE" -eq 0 ]; then
    echo 'Migrating MySQL schema to version 4.7...'
    $MYSQL_COMMAND -D "$PDNS_gmysql_dbname" < /usr/share/doc/pdns/4.3.0_to_4.7.0_schema.mysql.sql
  fi
}

initSuperslave() {
  if [ "${PDNS_autosecondary:-no}" = 'yes' ] || [ "${PDNS_superslave:-no}" = 'yes' ]; then
      # Configure supermasters if needed
      if [ "${SUPERMASTER_IPS:-}" ]; then
          $MYSQL_COMMAND -D "$PDNS_gmysql_dbname" -e 'TRUNCATE supermasters;'
          MYSQL_INSERT_SUPERMASTERS=''
          if [ "${SUPERMASTER_COUNT:-0}" -eq 0 ]; then
              SUPERMASTER_COUNT=10
          fi
          i=1; while [ $i -le "${SUPERMASTER_COUNT}" ]; do
              SUPERMASTER_HOST=$(echo "${SUPERMASTER_HOSTS:-}" | awk -v col="$i" '{ print $col }')
              SUPERMASTER_IP=$(echo "${SUPERMASTER_IPS}" | awk -v col="$i" '{ print $col }')
              if [ -z "${SUPERMASTER_HOST:-}" ]; then
                  SUPERMASTER_HOST=$(hostname -f)
              fi
              if [ "${SUPERMASTER_IP:-}" ]; then
                  MYSQL_INSERT_SUPERMASTERS="${MYSQL_INSERT_SUPERMASTERS} INSERT INTO supermasters VALUES('${SUPERMASTER_IP}', '${SUPERMASTER_HOST}', 'admin');"
              fi
              i=$(( i + 1 ))
          done
          $MYSQL_COMMAND -D "$PDNS_gmysql_dbname" -e "$MYSQL_INSERT_SUPERMASTERS"
      fi
  fi
}

generateAndInstallConfigFileFromEnvironment() {
  # Create config file from template
  subvars --prefix 'PDNS_' < '/pdns.conf.tpl' > '/etc/pdns/pdns.conf'
}

#### End of function definitions, let's get to work ...

if [ "${USE_EXISTING_CONFIG_FILE:-false}" = 'true' ]; then
  deriveMySQLSettingsFromExistingConfigFile
else
  deriveMySQLSettingsFromEnvironment
fi

generateMySQLCommand

# Wait for MySQL to respond
until $MYSQL_COMMAND -e ';' ; do
    >&2 echo 'MySQL is unavailable - sleeping'
    sleep 3
done

createDatabaseIfRequested
initDatabase
migrateDatabaseTo47
initSuperslave

if [ "${USE_EXISTING_CONFIG_FILE:-false}" = 'false' ]; then
  echo "(re-)generating config file from environment variables"
  generateAndInstallConfigFileFromEnvironment
fi

exec "$@"