def __init__(self, parser, name, validate=None, default_dict=None):
'''
New Section, used to describe options and validation
rules for a configuration section.
'''
# Validate validator callback if specified.
if validate:
_validate_validator(validate)
# Populate private attributes from call.
self._name = name
self._rule_list = list()
self._validator = validate
# Populate _value_dict from default dictionary, updating with
# data parsed from this configuration section.
self._value_dict = AttrDict()
if default_dict:
self._value_dict.update(default_dict.items())
self._value_dict.update(parser.items(name))
return
class Section(object):
'''Representation of a configuration section.'''
_msg_prefix_all = 'configuration validation error:'
_msg_prefix_section = ' '.join((_msg_prefix_all, 'section \'%s\':'))
_msg_prefix_option = ' '.join((_msg_prefix_section, 'option \'%s\':'))
def _make_option_exception(self, rule, msg):
'''Format and return an exception for an option validation error.'''
msg = (self._msg_prefix_option + ' %s') % (self.name, rule.option, msg)
return Config.ValidationError(msg)
def _make_section_exception(self, msg):
'''Format and return an exception for an section validation error.'''
msg = (self._msg_prefix_section + ' %s') % (self.name, msg)
return Config.ValidationError(msg)
#####
def __init__(self, parser, name, validate=None, default_dict=None):
'''
New Section, used to describe options and validation
rules for a configuration section.
'''
# Validate validator callback if specified.
if validate:
_validate_validator(validate)
# Populate private attributes from call.
self._name = name
self._rule_list = list()
self._validator = validate
# Populate _value_dict from default dictionary, updating with
# data parsed from this configuration section.
self._value_dict = AttrDict()
if default_dict:
self._value_dict.update(default_dict.items())
self._value_dict.update(parser.items(name))
return
#####
def __getattr__(self, attr):
'''Allow Section's value dictionary to be accessed as attribute.'''
return self._value_dict[attr.lower()]
#####
def __str__(self):
return '%s:%x' % (self._name, id(self))
#####
def add_rule(self, rule):
'''
Add OptionRule to this section. Returns section object so
that multiple invocations of this method call can be chained.
'''
# Validate that rule is subclass of expected type.
if not isinstance(rule, OptionRule):
raise TypeError('wrong type object %s' % str(rule))
# Append rule to internal rule list.
self._rule_list.append(rule)
return self
#####
def get_option(self, option_name):
'''Returns option by name.'''
return self.__getattr__(option_name)
#####
@property
def name(self):
'''Name of section.'''
return self._name
#####
def options(self):
'''Returns list of configuration options found for this section.'''
return sorted(self._value_dict.keys())
#####
def rules(self):
'''Returns list of option rules defined for this section.'''
return sorted(self._rule_list, key=lambda x : x.option)
#####
def validate(self):
'''Validate configuration section.'''
# List for errors accumulated by validation.
error_list = list()
# pylint: disable=E1101
logging.debug('validating section \'%s\'', self.name)
temp_value_dict = dict()
# Iterate over all defined rules.
for rule in self._rule_list:
# pylint: disable=E1101
logging.debug('validating option \'%s\'', rule.option)
# Does section have this attribute?
if not hasattr(self, rule.option):
# Append error to error list if option doesn't appear in
# options for section; skip further processing of this rule.
logging.debug('option \'%s\' missing', rule.option)
error_list.append(self._make_option_exception(rule,
'required option missing'))
continue
# If valid rule type specified, perform type conversion.
if rule.type:
try:
value = self._convert_type(rule)
temp_value_dict[rule.option.lower()] = value
except Config.ValidationError as exc:
error_list.append(exc)
# pylint: disable=W0703
except Exception as exc:
# Append any error produced by type conversion to
# error list.
log.log_exception()
error_list.append \
(self._make_option_exception(rule,
'EXCEPTION: %s' % exc))
# pylint: disable=E1101
logging.debug \
('option \'%s\' failed to convert to %s',
rule.option, rule.type.__name__)
continue
# pylint: disable=E1101
logging.debug \
('option \'%s\' converted to %s',
rule.option, rule.type.__name__)
else:
# No type converstion necessary for string option.
value = getattr(self, rule.option)
# If rule validator callback is specified, call it with
# AttrDict consisting of a single rule/value pair.
if rule.validator:
try:
# Call rule validator callback with converted value.
self._run_rule_validator(rule, value)
except Config.ValidationError as exc:
error_list.append(exc)
logging.debug('option \'%s\' failed to validate',
rule.option)
except Exception as exc:
# Log exception.
log.log_exception()
# Append error produced by rule validator to error list.
error_list.append(exc)
logging.debug('option \'%s\' failed to validate',
rule.option)
continue
logging.debug('option \'%s\' validated', rule.option)
# If section validator callback is specified, call it with
# AttrDict consisting of a single rule/value pair.
if self.validator:
try:
self._run_section_validator()
except Config.ValidationError as exc:
error_list.append(exc)
except Exception as exc:
# Log exception.
log.log_exception()
# Append error produced by validator callback to error list.
error_list.append(exc)
else:
logging.debug('section \'%s\' failed to validate', self)
# Process errors produced by any validation steps.
if error_list:
raise ConfigError(*error_list)
self._value_dict.update(temp_value_dict)
return
#####
@property
def validator(self):
'''Validator function reference.'''
return self._validator
#####
def _convert_type(self, rule):
'''Perform requested type conversion on specified rule.'''
try:
# Retrieve attribute value and perform type conversion.
value = rule.convert(getattr(self, rule.option))
except ValueError:
raise self._make_option_exception \
(rule, 'type conversion to %s failed' % rule.type.__name__)
# Method completed without error; return converted value.
return value
#####
def _run_rule_validator(self, rule, value):
'''Run validator callback on specified rule.'''
# pylint: disable=E1101
logging.debug('running rule validator %s for option \'%s\'',
rule.validator.__name__, rule.option)
try:
rule.validator(AttrDict({ rule.option : value }))
except Config.ValidationError as exc:
raise self._make_option_exception(rule, exc)
# Method completed without error.
return
#####
def _run_section_validator(self):
'''Run validator callback on Section.'''
# pylint: disable=E1101
logging.debug('running section validator %s',
self._validator.__name__)
try:
self.validator(self)
except Config.ValidationError as exc:
raise self._make_section_exception(exc)
# Method completed without error.
return
