diff options
Diffstat (limited to 'src/lib/Bcfg2/Options/Options.py')
| -rw-r--r-- | src/lib/Bcfg2/Options/Options.py | 201 |
1 files changed, 161 insertions, 40 deletions
diff --git a/src/lib/Bcfg2/Options/Options.py b/src/lib/Bcfg2/Options/Options.py index 3874f810d..752e01b4e 100644 --- a/src/lib/Bcfg2/Options/Options.py +++ b/src/lib/Bcfg2/Options/Options.py @@ -1,17 +1,23 @@ -""" The base :class:`Bcfg2.Options.Option` object represents an -option. Unlike options in :mod:`argparse`, an Option object does not -need to be associated with an option parser; it exists on its own.""" +"""Base :class:`Bcfg2.Options.Option` object to represent an option. -import os +Unlike options in :mod:`argparse`, an Option object does not need to +be associated with an option parser; it exists on its own. +""" + +import argparse import copy import fnmatch -import argparse +import os +import sys + from Bcfg2.Options import Types from Bcfg2.Compat import ConfigParser -__all__ = ["Option", "BooleanOption", "PathOption", "PositionalArgument", - "_debug"] +__all__ = ["Option", "BooleanOption", "RepositoryMacroOption", "PathOption", + "PositionalArgument", "_debug"] + +unit_test = False # pylint: disable=C0103 def _debug(msg): @@ -19,8 +25,11 @@ def _debug(msg): they're options, after all -- so option parsing verbosity is enabled by changing this to True. The verbosity here is primarily of use to developers. """ - if os.environ.get('BCFG2_OPTIONS_DEBUG', '0') == '1': - print(msg) + if unit_test: + print("DEBUG: %s" % msg) + elif os.environ.get('BCFG2_OPTIONS_DEBUG', '0').lower() in ["true", "yes", + "on", "1"]: + sys.stderr.write("%s\n" % msg) #: A dict that records a mapping of argparse action name (e.g., @@ -37,7 +46,7 @@ def _get_action_class(action_name): on. So we just instantiate a dummy parser, add a dummy argument, and determine the class that way. """ if (isinstance(action_name, type) and - issubclass(action_name, argparse.Action)): + issubclass(action_name, argparse.Action)): return action_name if action_name not in _action_map: action = argparse.ArgumentParser().add_argument(action_name, @@ -133,10 +142,11 @@ class Option(object): self._dest = None if 'dest' in self._kwargs: self._dest = self._kwargs.pop('dest') - elif self.cf is not None: - self._dest = self.cf[1] elif self.env is not None: self._dest = self.env + elif self.cf is not None: + self._dest = self.cf[1] + self._dest = self._dest.lower().replace("-", "_") kwargs = copy.copy(self._kwargs) kwargs.pop("action", None) self.actions[None] = action_cls(self._dest, self._dest, **kwargs) @@ -149,9 +159,10 @@ class Option(object): sources.append("%s.%s" % self.cf) if self.env: sources.append("$" + self.env) - spec = ["sources=%s" % sources, "default=%s" % self.default] - spec.append("%d parsers" % (len(self.parsers))) - return 'Option(%s: %s)' % (self.dest, ", ".join(spec)) + spec = ["sources=%s" % sources, "default=%s" % self.default, + "%d parsers" % len(self.parsers)] + return '%s(%s: %s)' % (self.__class__.__name__, + self.dest, ", ".join(spec)) def list_options(self): """ List options contained in this option. This exists to @@ -175,6 +186,17 @@ class Option(object): _debug("Finalizing %s" % self) action.finalize(parser, namespace) + @property + def _type_func(self): + """get a function for converting a value to the option type. + + this always returns a callable, even when ``type`` is None. + """ + if self.type: + return self.type + else: + return lambda x: x + def from_config(self, cfp): """ Get the value of this option from the given :class:`ConfigParser.ConfigParser`. If it is not found in the @@ -201,21 +223,33 @@ class Option(object): self.cf[1]) if o not in exclude]) else: - rv = dict() + rv = {} else: - if self.type: - rtype = self.type - else: - rtype = lambda x: x try: - rv = rtype(cfp.getboolean(*self.cf)) - except ValueError: - rv = rtype(cfp.get(*self.cf)) + rv = self._type_func(self.get_config_value(cfp)) except (ConfigParser.NoSectionError, ConfigParser.NoOptionError): rv = None - _debug("Setting %s from config file(s): %s" % (self, rv)) + _debug("Getting value of %s from config file(s): %s" % (self, rv)) return rv + def get_config_value(self, cfp): + """fetch a value from the config file. + + This is passed the config parser. Its result is passed to the + type function for this option. It can be overridden to, e.g., + handle boolean options. + """ + return cfp.get(*self.cf) + + def get_environ_value(self, value): + """fetch a value from the environment. + + This is passed the raw value from the environment variable, + and its result is passed to the type function for this + option. It can be overridden to, e.g., handle boolean options. + """ + return value + def default_from_config(self, cfp): """ Set the default value of this option from the config file or from the environment. @@ -224,7 +258,8 @@ class Option(object): :type cfp: ConfigParser.ConfigParser """ if self.env and self.env in os.environ: - self.default = os.environ[self.env] + self.default = self._type_func( + self.get_environ_value(os.environ[self.env])) _debug("Setting the default of %s from environment: %s" % (self, self.default)) else: @@ -257,6 +292,13 @@ class Option(object): for action in self.actions.values(): action.dest = value + def early_parsing_hook(self, early_opts): # pylint: disable=C0111 + """Hook called at the end of early option parsing. + + This can be used to save option values for macro fixup. + """ + pass + #: The namespace destination of this option (see `dest #: <http://docs.python.org/dev/library/argparse.html#dest>`_) dest = property(_get_dest, _set_dest) @@ -284,13 +326,65 @@ class Option(object): (self, parser)) -class PathOption(Option): - """ Shortcut for options that expect a path argument. Uses - :meth:`Bcfg2.Options.Types.path` to transform the argument into a - canonical path. +class RepositoryMacroOption(Option): + """Option that does translation of ``<repository>`` macros. - The type of a path option can also be overridden to return an - option file-like object. For example: + Macro translation is done on the fly instead of just fixing up all + values at the end of parsing because macro expansion needs to be + done before path canonicalization for + :class:`Bcfg2.Options.Options.PathOption`. + """ + repository = None + + def __init__(self, *args, **kwargs): + self._original_type = kwargs.pop('type', lambda x: x) + kwargs['type'] = self._type + kwargs.setdefault('metavar', '<path>') + Option.__init__(self, *args, **kwargs) + + def early_parsing_hook(self, early_opts): + if hasattr(early_opts, "repository"): + if self.__class__.repository is None: + _debug("Setting repository to %s for %s" % + (early_opts.repository, self.__class__.__name__)) + self.__class__.repository = early_opts.repository + else: + _debug("Repository is already set for %s" % self.__class__) + + def _get_default(self): + """ Getter for the ``default`` property """ + if not hasattr(self._default, "replace"): + return self._default + else: + return self._type(self._default) + + default = property(_get_default, Option._set_default) + + def transform_value(self, value): + """transform the value after macro expansion. + + this can be overridden to further transform the value set by + the user *after* macros are expanded, but before the user's + ``type`` function is applied. principally exists for + PathOption to canonicalize the path. + """ + return value + + def _type(self, value): + """Type function that fixes up <repository> macros.""" + if self.__class__.repository is None: + return value + else: + return self._original_type(self.transform_value( + value.replace("<repository>", self.__class__.repository))) + + +class PathOption(RepositoryMacroOption): + """Shortcut for options that expect a path argument. + + Uses :meth:`Bcfg2.Options.Types.path` to transform the argument + into a canonical path. The type of a path option can also be + overridden to return a file-like object. For example: .. code-block:: python @@ -298,30 +392,41 @@ class PathOption(Option): Bcfg2.Options.PathOption( "--input", type=argparse.FileType('r'), help="The input file")] - """ - def __init__(self, *args, **kwargs): - kwargs.setdefault('type', Types.path) - kwargs.setdefault('metavar', '<path>') - Option.__init__(self, *args, **kwargs) + PathOptions also do translation of ``<repository>`` macros. + """ + def transform_value(self, value): + return Types.path(value) class _BooleanOptionAction(argparse.Action): - """ BooleanOptionAction sets a boolean value in the following ways: + """BooleanOptionAction sets a boolean value. + - if None is passed, store the default - if the option_string is not None, then the option was passed on the command line, thus store the opposite of the default (this is the argparse store_true and store_false behavior) - if a boolean value is passed, use that + Makes a copy of the initial default, because otherwise the default + can be changed by config file settings or environment + variables. For instance, if a boolean option that defaults to True + was set to False in the config file, specifying the option on the + CLI would then set it back to True. + Defined here instead of :mod:`Bcfg2.Options.Actions` because otherwise - there is a circular import Options -> Actions -> Parser -> Options """ + there is a circular import Options -> Actions -> Parser -> Options. + """ + + def __init__(self, *args, **kwargs): + argparse.Action.__init__(self, *args, **kwargs) + self.original = self.default def __call__(self, parser, namespace, values, option_string=None): if values is None: setattr(namespace, self.dest, self.default) elif option_string is not None: - setattr(namespace, self.dest, not self.default) + setattr(namespace, self.dest, not self.original) else: setattr(namespace, self.dest, bool(values)) @@ -340,9 +445,25 @@ class BooleanOption(Option): kwargs.setdefault('action', _BooleanOptionAction) kwargs.setdefault('nargs', 0) kwargs.setdefault('default', False) - Option.__init__(self, *args, **kwargs) + def get_environ_value(self, value): + if value.lower() in ["false", "no", "off", "0"]: + return False + elif value.lower() in ["true", "yes", "on", "1"]: + return True + else: + raise ValueError("Invalid boolean value %s" % value) + + def get_config_value(self, cfp): + """fetch a value from the config file. + + This is passed the config parser. Its result is passed to the + type function for this option. It can be overridden to, e.g., + handle boolean options. + """ + return cfp.getboolean(*self.cf) + class PositionalArgument(Option): """ Shortcut for positional arguments. """ |