# Copyright 2019 VyOS maintainers and contributors <maintainers@vyos.io> # # This library is free software; you can redistribute it and/or # modify it under the terms of the GNU Lesser General Public # License as published by the Free Software Foundation; either # version 2.1 of the License, or (at your option) any later version. # # This library is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU # Lesser General Public License for more details. # # You should have received a copy of the GNU Lesser General Public License # along with this library. If not, see <http://www.gnu.org/licenses/>. import sys import os import subprocess import vyos.version import vyos.defaults import vyos.systemversions as systemversions import vyos.formatversions as formatversions class MigratorError(Exception): pass class Migrator(object): def __init__(self, config_file, force=False, set_vintage='vyos'): self._config_file = config_file self._force = force self._set_vintage = set_vintage self._config_file_vintage = None self._log_file = None self._changed = False def read_config_file_versions(self): """ Get component versions from config file footer and set vintage; return empty dictionary if config string is missing. """ cfg_file = self._config_file component_versions = {} cfg_versions = formatversions.read_vyatta_versions(cfg_file) if cfg_versions: self._config_file_vintage = 'vyatta' component_versions = cfg_versions cfg_versions = formatversions.read_vyos_versions(cfg_file) if cfg_versions: self._config_file_vintage = 'vyos' component_versions = cfg_versions return component_versions def update_vintage(self): old_vintage = self._config_file_vintage if self._set_vintage: self._config_file_vintage = self._set_vintage if self._config_file_vintage not in ['vyatta', 'vyos']: raise MigratorError("Unknown vintage.") if self._config_file_vintage == old_vintage: return False else: return True def open_log_file(self): """ Open log file for migration, catching any error. Note that, on boot, migration takes place before the canonical log directory is created, hence write to the config file directory. """ self._log_file = os.path.join(vyos.defaults.directories['config'], 'vyos-migrate.log') # on creation, allow write permission for cfg_group; # restore original umask on exit mask = os.umask(0o113) try: log = open('{0}'.format(self._log_file), 'w') log.write("List of executed migration scripts:\n") except Exception as e: os.umask(mask) print("Logging error: {0}".format(e)) return None os.umask(mask) return log def run_migration_scripts(self, config_file_versions, system_versions): """ Run migration scripts iteratively, until config file version equals system component version. """ log = self.open_log_file() cfg_versions = config_file_versions sys_versions = system_versions sys_keys = list(sys_versions.keys()) sys_keys.sort() rev_versions = {} for key in sys_keys: sys_ver = sys_versions[key] if key in cfg_versions: cfg_ver = cfg_versions[key] else: cfg_ver = 0 migrate_script_dir = os.path.join( vyos.defaults.directories['migrate'], key) while cfg_ver < sys_ver: next_ver = cfg_ver + 1 migrate_script = os.path.join(migrate_script_dir, '{}-to-{}'.format(cfg_ver, next_ver)) try: subprocess.check_call([migrate_script, self._config_file]) except FileNotFoundError: pass except Exception as err: print("\nMigration script error: {0}: {1}." "".format(migrate_script, err)) sys.exit(1) if log: try: log.write('{0}\n'.format(migrate_script)) except Exception as e: print("Error writing log: {0}".format(e)) cfg_ver = next_ver rev_versions[key] = cfg_ver if log: log.close() return rev_versions def write_config_file_versions(self, cfg_versions): """ Write new versions string. """ versions_string = formatversions.format_versions_string(cfg_versions) os_version_string = vyos.version.get_version() if self._config_file_vintage == 'vyatta': formatversions.write_vyatta_versions_foot(self._config_file, versions_string, os_version_string) if self._config_file_vintage == 'vyos': formatversions.write_vyos_versions_foot(self._config_file, versions_string, os_version_string) def run(self): """ Gather component versions from config file and system. Run migration scripts. Update vintage ('vyatta' or 'vyos'), if needed. If changed, remove old versions string from config file, and write new versions string. """ cfg_file = self._config_file cfg_versions = self.read_config_file_versions() if self._force: # This will force calling all migration scripts: cfg_versions = {} sys_versions = systemversions.get_system_versions() rev_versions = self.run_migration_scripts(cfg_versions, sys_versions) if rev_versions != cfg_versions: self._changed = True if self.update_vintage(): self._changed = True if not self._changed: return formatversions.remove_versions(cfg_file) self.write_config_file_versions(rev_versions) def config_changed(self): return self._changed class VirtualMigrator(Migrator): def run(self): cfg_file = self._config_file cfg_versions = self.read_config_file_versions() if not cfg_versions: return if self.update_vintage(): self._changed = True if not self._changed: return formatversions.remove_versions(cfg_file) self.write_config_file_versions(cfg_versions)