diff options
| -rw-r--r-- | python/vyos/compose_config.py | 84 | ||||
| -rw-r--r-- | python/vyos/configtree.py | 10 |
2 files changed, 93 insertions, 1 deletions
diff --git a/python/vyos/compose_config.py b/python/vyos/compose_config.py new file mode 100644 index 000000000..efa28babe --- /dev/null +++ b/python/vyos/compose_config.py @@ -0,0 +1,84 @@ +# Copyright 2024 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/>. + +"""This module allows iterating over function calls to modify an existing +config. +""" + +from pathlib import Path +from typing import TypeAlias, Union, Callable + +from vyos.configtree import ConfigTree +from vyos.configtree import deep_copy as ct_deep_copy +from vyos.utils.system import load_as_module + +ConfigObj: TypeAlias = Union[str, ConfigTree] + +class ComposeConfigError(Exception): + """Raised when an error occurs modifying a config object. + """ + +class ComposeConfig: + """Apply function to config tree: for iteration over functions or files. + """ + def __init__(self, config_obj: ConfigObj, checkpoint_file=None): + if isinstance(config_obj, ConfigTree): + self.config_tree = config_obj + else: + self.config_tree = ConfigTree(config_obj) + + self.checkpoint = self.config_tree + self.checkpoint_file = checkpoint_file + + def apply_func(self, func: Callable): + """Apply the function to the config tree. + """ + if not callable(func): + raise ComposeConfigError(f'{func.__name__} is not callable') + + if self.checkpoint_file is not None: + self.checkpoint = ct_deep_copy(self.config_tree) + + try: + func(self.config_tree) + except Exception as e: + self.config_tree = self.checkpoint + raise ComposeConfigError(e) from e + + def apply_file(self, func_file: str, func_name: str): + """Apply named function from file. + """ + try: + mod_name = Path(func_file).stem.replace('-', '_') + mod = load_as_module(mod_name, func_file) + func = getattr(mod, func_name) + except Exception as e: + raise ComposeConfigError(f'Error with {func_file}: {e}') from e + + try: + self.apply_func(func) + except ComposeConfigError as e: + raise ComposeConfigError(f'Error in {func_file}: {e}') from e + + def to_string(self, with_version=False) -> str: + """Return the rendered config tree. + """ + return self.config_tree.to_string(no_version=not with_version) + + def write(self, config_file: str, with_version=False): + """Write the config tree to a file. + """ + config_str = self.to_string(with_version=with_version) + Path(config_file).write_text(config_str) diff --git a/python/vyos/configtree.py b/python/vyos/configtree.py index e4b282d72..afd6e030b 100644 --- a/python/vyos/configtree.py +++ b/python/vyos/configtree.py @@ -175,9 +175,11 @@ class ConfigTree(object): def get_version_string(self): return self.__version - def to_string(self, ordered_values=False): + def to_string(self, ordered_values=False, no_version=False): config_string = self.__to_string(self.__config, ordered_values).decode() config_string = unescape_backslash(config_string) + if no_version: + return config_string config_string = "{0}\n{1}".format(config_string, self.__version) return config_string @@ -482,3 +484,9 @@ class DiffTree: add = self.add.to_commands() delete = self.delete.to_commands(op="delete") return delete + "\n" + add + +def deep_copy(config_tree: ConfigTree) -> ConfigTree: + """An inelegant, but reasonably fast, copy; replace with backend copy + """ + D = DiffTree(None, config_tree) + return D.add |