# Copyright (c) 2012-2016 Lars Hupfeldt Nielsen, Hupfeldt IT
# All rights reserved. This work is under a BSD license, see LICENSE.TXT.
from __future__ import print_function
import sys, os, traceback
from collections import OrderedDict
import json
import threading
from .envs import EnvFactory, Env, MissingValueEnvException, AmbiguousEnvException, EnvException, MC_NO_ENV, thread_local
from .values import MC_NO_VALUE, MC_TODO, MC_REQUIRED, McTodoHandling
from .attribute import _McAttribute, _McAttributeAccessor, Where
from .property_wrapper import _McPropertyWrapper
from .repeatable import RepeatableDict
from .config_errors import ConfigException, ConfigApiException, InvalidUsageException, ConfigExcludedAttributeError, ConfigExcludedKeyError
from .config_errors import caller_file_line, find_user_file_line, _line_msg, _error_msg, _warning_msg, not_repeatable_in_parent_msg, repeatable_in_parent_msg
from .json_output import ConfigItemEncoder, _mc_filter_out_keys, _mc_identification_msg_str
from . import typecheck
major_version = sys.version_info[0]
class _McExcludedException(Exception):
pass
_mc_debug_enabled = str(os.environ.get('MULTICONF_DEBUG')).lower() == 'true'
def _mc_debug(*args):
if _mc_debug_enabled:
print(*args)
class _ConfigBase(object):
_mc_last_item = None
_mc_built_by = None
_mc_hierarchy = []
_mc_deco_named_as = None
_mc_deco_required = ()
_mc_deco_nested_repeatables = ()
@classmethod
def _mc_debug_hierarchy(cls, msg):
_mc_debug(
msg,
cls if not isinstance(cls, _ConfigBase) else (type(cls), id(cls)),
'_mc_hierarchy: {}'.format([id(item) for item in cls._mc_hierarchy]))
def _mc_error_msg(self, message):
self._mc_num_errors += 1
return _error_msg(message)
def _mc_warning_msg(self, msg):
self._mc_root._mc_num_warnings += 1
return _warning_msg(msg)
def _mc_raise_errors(self, already="\nCheck already printed error messages"):
nerr = self._mc_num_errors
ww, err = ('were', 'errors') if nerr > 1 else ('was', 'error')
msg = "There {ww} {nerr} {err} when defining item: {self}{already}.".format(ww=ww, nerr=nerr, err=err, self=self, already=already)
raise ConfigException(msg, is_summary = True)
def _mc_print_error(self, message, file_name, line_num):
"""Print a single message preceded by file:line"""
print(_line_msg(file_name=file_name, line_num=line_num) + '\n' + self._mc_error_msg(message), file=sys.stderr)
def _mc_print_error_caller_unchecked(self, message, mc_error_info_up_level):
"""Print a single message preceded by file:line. The caller is responsible for checking if self is frozen."""
file_name, line_num = caller_file_line(up_level=mc_error_info_up_level + 1)
print(_line_msg(file_name=file_name, line_num=line_num) + '\n' + self._mc_error_msg(message), file=sys.stderr)
def _mc_print_error_caller(self, message, mc_error_info_up_level):
"""Print a single message preceded by file:line. If self is frozen then raise error immediately."""
self._mc_print_error_caller_unchecked(message, mc_error_info_up_level + 1)
if self._mc_where == Where.FROZEN:
# We need to raise now, self is already frozen so error count will not be checked later
self._mc_raise_errors()
def _mc_print_warning(self, message, file_name, line_num):
"""Print a single message preceded by file:line"""
print(_line_msg(file_name=file_name, line_num=line_num) + '\n' + self._mc_warning_msg(message), file=sys.stderr)
def _mc_print_value_error_msg(self, attr_name, value, mc_caller_file_name, mc_caller_line_num):
"""Print message about invalid or missing value"""
cr = self._mc_root
current_env = thread_local.env
value_msg = ' ' + repr(value) if value != MC_NO_VALUE else ''
msg = "Attribute: '{attr}'{value_msg} did not receive a value for env {env}".format(attr=attr_name, value_msg=value_msg, env=current_env)
if value == MC_TODO:
cr._mc_todo_msgs[current_env].append((msg, mc_caller_file_name, mc_caller_line_num))
todo_handling = cr._mc_todo_handling_allowed if current_env.allow_todo else cr._mc_todo_handling_other
if todo_handling is McTodoHandling.SILENT:
return
if todo_handling is McTodoHandling.WARNING:
self._mc_print_warning(msg, file_name=mc_caller_file_name, line_num=mc_caller_line_num)
return
self._mc_print_error(msg, file_name=mc_caller_file_name, line_num=mc_caller_line_num)
def _mc_print_no_proper_value_error_msg(self, mc_error_info_up_level):
msg = "The following attribues defined earlier never received a proper value for {env}:".format(env=self.env)
if mc_error_info_up_level is not None:
mc_caller_file_name, mc_caller_line_num = find_user_file_line(up_level_start=mc_error_info_up_level + 1)
print(_line_msg(file_name=mc_caller_file_name, line_num=mc_caller_line_num), file=sys.stderr)
print(_error_msg(msg), file=sys.stderr)
for attr_name, info in self._mc_attributes_to_check.items():
where_from, value_file_name, value_line_num = info # TODO, 'use where'_from in error message
value = getattr(self, attr_name)
self._mc_print_value_error_msg(attr_name, value, value_file_name, value_line_num)
@classmethod
def named_as(cls):
"""Return the named_as property set by the @named_as decorator"""
return cls._mc_deco_named_as or cls.__name__
def json(self, compact=False, sort_attributes=False, property_methods=True, builders=False, skipkeys=True, warn_nesting=None, show_all_envs=False,
depth=None, persistent_ids=False):
"""Create json representation of configuration.
The mc_json_filter and mc_json_fallback arguments to :func:`mc_config` also influence the output.
Arguments:
compact (bool): Set compact to true if dumping for easier human readable output, false for machine readable output.
sort_attributes (bool): Sort attributes by name. Sort dir() entries by name.
property_methods (bool or None): Call @property methods and insert values in output, including a comment that the value is calculated.
If `property_methods` is None the @property method is not called but the name is still output, with the value replace by a fixed
message. False completely disables information about @property methods.
builders (bool): Include ConfigBuilder items in json.
skipkeys (bool): Passed to json.dumps.
show_all_envs (bool): Display attribute values for all envs in a single dump. Without this only the values for the current env is displayed.
depth (int): The number of levels of child objects to dump. None means all.
persistent_ids (bool): Use a persistent value instead of using id(obj) as reference keys.
NOTE: This will mostly make it impossible to identify the referenced obj, but it makes it possible to compare json across runs.
"""
cr = self._mc_root
filter_callable = cr._mc_json_filter
fallback_callable = cr._mc_json_fallback
encoder = ConfigItemEncoder(
filter_callable=filter_callable, fallback_callable=fallback_callable,
compact=compact, sort_attributes=sort_attributes, property_methods=property_methods,
builders=builders, warn_nesting=warn_nesting,
multiconf_base_type=_ConfigBase, multiconf_builder_type=_ConfigBuilder,
multiconf_property_wrapper_type=_McPropertyWrapper,
show_all_envs=show_all_envs,
depth=depth,
persistent_ids=persistent_ids)
cr._mc_in_json = True
# Disable attribute setting to avoid side effects from calling json if @property methods set mc attributes
_ConfigBase._mc_setattr = _ConfigBase._mc_setattr_disabled
try:
orig_env = thread_local.env
if show_all_envs:
thread_local.env = MC_NO_ENV
# python3 doesn't need separators=(',', ': ')
json_str = json.dumps(self, skipkeys=skipkeys, default=encoder, check_circular=False, sort_keys=False, indent=4, separators=(',', ': '))
cr._mc_json_errors = encoder.num_errors
return json_str
finally:
_ConfigBase._mc_setattr = _ConfigBase._mc_setattr_real
cr._mc_in_json = False
thread_local.env = orig_env
def _mc_excl_repr(self):
return "Excluded: " + repr(type(self))
def __repr__(self):
if self:
# Don't call @property methods in repr, it is too dangerous, leading to double errors (endless loops) in case of incorrect user
# implemented @property methods. We only insert the method name and a predefined message in the generated json.
return self.json(compact=True, property_methods=None, builders=True, depth=None)
return self._mc_excl_repr()
def num_json_errors(self):
"""
Returns number of errors encountered when generating json
Return 0 if json() has not been called
"""
return self._mc_root._mc_json_errors
def mc_init(self):
"""This is a user defined callback method.
This is called at the exit from a with statement.
May be used for e.g. setting default values based on other properties or cross validation of different properties
"""
def mc_validate(self):
"""This is a user defined callback method.
This method is called once for each item for each env after other initialization has been and all items are created.
May be used for e.g. setting default values based on other properties or cross validation of different properties.
It is preferable to use mc_init when possible as mc_init generally results in more precise error messages, and ensures that an
item is fully defined when the 'with' statement is exited.
"""
def mc_post_validate(self):
"""This is a user defined callback method.
This method is called once for each item after other initialization has been done for all envs, so cross env checking and cross
object/attribute checking is possible. Since it is called once, and not per env, there is no current env and regular attribute
access is not possible, instead the item.getattr(name, env) method must be used to get attribute values for different envs.
This makes it possible to implement checks like the following::
assert item.getattr('mem_size', pprd) == item.getattr('mem_size', prod) <= item.getattr('mem_size', tst1)
Note that careful consideration should be taken when using env names explicitly (as above) when implementing a configuration
object model, since this will force all configurations to define those envs.
Note that no modifications can be done in this method!
"""
def __bool__(self):
return bool(self._mc_exists_in_env())
# Python2 compatibility
__nonzero__ = __bool__
if major_version >= 3: # This should have been an else, but that makes it difficult to do the coverage
def __dir__(self):
return [name for name in object.__dir__(self)
if not isinstance(getattr(self.__class__, name, None), _McAttributeAccessor) or name in self._mc_attributes]
def _mc_exists_in_given_env(self, env):
return self._mc_handled_env_bits & env.mask
def _mc_exists_in_env(self):
env_mask = thread_local.env.mask
return self._mc_handled_env_bits & env_mask or env_mask == 0
def _mc_freeze(self, mc_error_info_up_level):
if not self:
self._mc_where = Where.FROZEN
return
if self._mc_num_errors:
self._mc_raise_errors()
self._mc_where = Where.IN_MC_INIT
must_pop = False
if self.__class__._mc_hierarchy[-1] != self:
must_pop = True
self.__class__._mc_hierarchy.append(self)
# Call user 'mc_init' callback
self.mc_init()
if self._mc_attributes_to_check and self.mc_validate.__code__ is _ConfigBase.mc_validate.__code__:
self._mc_print_no_proper_value_error_msg(mc_error_info_up_level)
if isinstance(self, _ConfigBuilder):
self._mc_builder_freeze()
# New items may have been created in mc_init
self._mc_freeze_previous(mc_error_info_up_level)
if must_pop:
self.__class__._mc_hierarchy.pop()
missing_req = []
for req in self._mc_deco_required:
if not req in self._mc_items:
missing_req.append(req)
if missing_req:
if mc_error_info_up_level is not None:
mc_caller_file_name, mc_caller_line_num = find_user_file_line(up_level_start=mc_error_info_up_level)
print(_line_msg(file_name=mc_caller_file_name, line_num=mc_caller_line_num), file=sys.stderr)
print(self._mc_error_msg("Missing '@required' items: {}".format(missing_req)), file=sys.stderr)
if self._mc_num_errors:
self._mc_raise_errors()
self._mc_where = Where.FROZEN
def _mc_freeze_previous(self, mc_error_info_up_level):
previous_item = _ConfigBase._mc_last_item
if previous_item is not self and previous_item is not self._mc_contained_in and previous_item and previous_item._mc_where != Where.FROZEN:
previous_item._mc_freeze(mc_error_info_up_level + 1 if mc_error_info_up_level is not None else None)
def _mc_call_mc_validate_recursively(self, env):
"""Call the user defined 'mc_validate' methods on all items"""
if not self._mc_exists_in_given_env(env):
return
self._mc_where = Where.NOWHERE
self.mc_validate()
if self._mc_attributes_to_check:
self._mc_print_no_proper_value_error_msg(None)
if self._mc_num_errors:
self._mc_raise_errors()
self._mc_where = Where.FROZEN
for child_item in self._mc_items.values():
child_item._mc_call_mc_validate_recursively(env)
def _mc_validate_properties_recursively(self, env):
"""Validate that @property methods can be called without error"""
if not self._mc_exists_in_given_env(env):
return
for key in self.__class__._mc_cls_dir_entries:
if key.startswith('_') or key in self._mc_attributes or key in self._mc_items or key in _mc_filter_out_keys:
continue
try:
val = getattr(self, key)
except InvalidUsageException:
self._mc_root._mc_num_invalid_property_usage += 1
# print(_error_msg("InvalidUsageException trying to validate @property '{prop_name}' in {env}.".format(prop_name=key, env=env)), file=sys.stderr)
# traceback.print_exception(*sys.exc_info())
except Exception as ex:
self._mc_root._mc_num_property_errors += 1
print(_error_msg("Exception validating @property '{prop_name}' on item {item} in {env}.".format(
prop_name=key, item=_mc_identification_msg_str(self), env=env)), file=sys.stderr)
traceback.print_exception(*sys.exc_info())
for child_item in self._mc_items.values():
child_item._mc_validate_properties_recursively(env)
@property
def num_invalid_property_usage(self):
"""Returns number of 'InvalidUsageException' s encountered when validating @property methods
Returns 0 if 'mc_config' was called with validate_properties=False.
"""
return self._mc_root._mc_num_invalid_property_usage
def _mc_call_mc_post_validate_recursively(self):
"""Call the user defined 'mc_post_validate' methods on all items"""
self._mc_where = Where.NOWHERE
self.mc_post_validate()
self._mc_where = Where.FROZEN
for child_item in self._mc_items.values():
child_item._mc_call_mc_post_validate_recursively()
def __enter__(self):
self._mc_where = Where.IN_WITH if self._mc_where != Where.IN_RE_INIT else Where.IN_RE_WITH
self.__class__._mc_hierarchy.append(self)
# self.__class__._mc_debug_hierarchy('_ConfigBase.__enter__')
return self
def __exit__(self, exc_type, value, traceback):
if not exc_type:
self._mc_freeze_previous(mc_error_info_up_level=1)
self._mc_freeze(mc_error_info_up_level=1)
self.__class__._mc_hierarchy.pop()
return None
# self.__class__._mc_debug_hierarchy('_ConfigBase.__exit__')
if exc_type is _McExcludedException:
self.__class__._mc_hierarchy.pop()
return True
def _mc_setattr_env_value(self, current_env, attr_name, env_attr, value, old_value, from_eg, mc_force, mc_error_info_up_level, mc_5_migration):
# print("_mc_setattr_env_value:", current_env, attr_name, value, old_value)
if old_value != MC_NO_VALUE and not mc_force:
if self._mc_where == Where.IN_MC_INIT and env_attr.where_from != Where.IN_MC_INIT and old_value != MC_REQUIRED:
# In mc_init we will not overwrite a proper value set previously unless the eg is more specific than the previous one or mc_force is used
if not mc_5_migration:
if from_eg not in env_attr.from_eg or from_eg == env_attr.from_eg:
return
else:
# or previous value was set in __init__ and the env is at least as specific and mc_5_migration is set
if from_eg not in env_attr.from_eg:
if env_attr.where_from != Where.IN_INIT:
return
if from_eg != env_attr.from_eg:
return
if self._mc_where == Where.IN_RE_INIT and env_attr.where_from != Where.IN_RE_INIT and old_value != MC_REQUIRED:
# In mc_re_init we will not overwrite a proper value set previously unless the eg is more specific than the previous one or mc_force is used
if from_eg not in env_attr.from_eg or from_eg == env_attr.from_eg:
return
if self._mc_where == Where.IN_RE_WITH and env_attr.where_from == Where.IN_RE_WITH:
# Trying to set the same attribute again in with block
msg = "The attribute '{attr_name}' is already fully defined.".format(attr_name=attr_name)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
if self._mc_where == Where.IN_WITH and env_attr.where_from == Where.IN_WITH:
# Trying to set the same attribute again in with block
msg = "The attribute '{attr_name}' is already fully defined.".format(attr_name=attr_name)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
if env_attr.where_from == Where.FROZEN:
msg = "Trying to set attribute '{attr_name}'. ".format(attr_name=attr_name)
msg += "Setting attributes is not allowed after value has been used (in order to enforce derived value validity)."
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
if self._mc_where == Where.FROZEN:
msg = "Trying to set attribute '{attr_name}'. ".format(attr_name=attr_name)
msg += "Setting attributes is not allowed after item is 'frozen' (with 'scope' is exited)."
self._mc_print_error_caller(msg, mc_error_info_up_level) # Note: This always raises en exception
if value == MC_NO_VALUE:
if old_value not in (MC_NO_VALUE, MC_TODO, MC_REQUIRED):
return
value = old_value
if value != MC_NO_VALUE:
# We have a value for the env which is more specific than any previous value
env_attr.set(current_env, value, self._mc_where, from_eg)
if value not in (MC_TODO, MC_REQUIRED):
if self._mc_root._mc_do_type_check:
type_msg = typecheck.type_check(self, attr_name, value)
if type_msg:
self._mc_print_error_caller(type_msg, mc_error_info_up_level)
return
if self._mc_attributes_to_check:
self._mc_attributes_to_check.pop(attr_name, None)
return
if self._mc_where == Where.IN_INIT or not self:
if value == MC_NO_VALUE:
env_attr.set(current_env, value, self._mc_where, from_eg)
# This is not an error now, as we allow partial set in __init__ and setting value to MC_REQUIRED in 'with' block
# to postpone check until after 'mc_init', but we must remember to test later if the attribute has been set.
mc_caller_file_name, mc_caller_line_num = caller_file_line(up_level=mc_error_info_up_level)
if self._mc_attributes_to_check is None:
self._mc_attributes_to_check = OrderedDict()
self._mc_attributes_to_check[attr_name] = (self._mc_where, mc_caller_file_name, mc_caller_line_num)
return
# We will report the error now, so pop from check list
if self._mc_attributes_to_check:
self._mc_attributes_to_check.pop(attr_name, None)
mc_caller_file_name, mc_caller_line_num = caller_file_line(up_level=mc_error_info_up_level)
self._mc_print_value_error_msg(attr_name, value, mc_caller_file_name, mc_caller_line_num)
def _mc_check_no_existing_attr(self, attr_name, mc_overwrite_property, mc_set_unknown, mc_error_info_up_level):
if attr_name in self._mc_items:
# Non-Repeatable ConfigItems are not defined at the class level, only at instance level and in _mc_items
item = self._mc_items[attr_name]
msg = "'{name}' {typ} is already defined and may not be replaced with an attribute.".format(name=attr_name, typ=type(item))
self._mc_print_error_caller(msg, mc_error_info_up_level)
return True
if mc_overwrite_property:
msg = "'mc_overwrite_property' is True but no property named '{name}' exists.".format(name=attr_name)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return True
if self._mc_where not in (Where.IN_INIT, Where.IN_RE_INIT) and not mc_set_unknown:
msg = "All attributes must be defined in __init__ or set with 'mc_set_unknown'. " + \
"Attempting to set attribute '{attr_name}' which does not exist.".format(attr_name=attr_name)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return True
return False
def _mc_setattr(
self, current_env, attr_name, value, from_eg, mc_overwrite_property, mc_set_unknown, mc_force, mc_error_info_up_level,
mc_5_migration=False, is_assign=False):
"""Common code for assignment and item.setattr"""
#_mc_debug("_mc_setattr:", current_env, attr_name, value)
try:
cls_attr = getattr(self.__class__, attr_name)
# print("_mc_setattr, cls_attr:", type(cls_attr))
except AttributeError as ex:
#_mc_debug("_mc_setattr, AttributeError:", ex)
if self._mc_check_no_existing_attr(attr_name, mc_overwrite_property, mc_set_unknown, mc_error_info_up_level+1):
return
# print("_mc_setattr creating new _McAttributeAccessor")
setattr(self.__class__, attr_name, _McAttributeAccessor(attr_name))
env_attr = _McAttribute()
self._mc_attributes[attr_name] = env_attr
self._mc_setattr_env_value(current_env, attr_name, env_attr, value, MC_NO_VALUE, from_eg, mc_force, mc_error_info_up_level + 1, mc_5_migration)
else:
if isinstance(cls_attr, _McAttributeAccessor):
# print("_mc_setattr found _McAttributeAccessor")
env_attr = self._mc_attributes.get(attr_name)
if env_attr is None:
if self._mc_check_no_existing_attr(attr_name, mc_overwrite_property, mc_set_unknown, mc_error_info_up_level+1):
return
env_attr = _McAttribute()
self._mc_attributes[attr_name] = env_attr
old_value = MC_NO_VALUE
else:
old_value = env_attr.env_values.get(current_env, MC_NO_VALUE)
if mc_set_unknown and old_value != MC_NO_VALUE:
msg = "Attempting to use 'mc_set_unknown' to set attribute '{attr_name}' which already exists.".format(attr_name=attr_name)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
self._mc_setattr_env_value(current_env, attr_name, env_attr, value, old_value, from_eg, mc_force, mc_error_info_up_level + 1, mc_5_migration)
return
if isinstance(cls_attr, _McPropertyWrapper):
#_mc_debug("_mc_setattr found _McPropertyWrapper")
if value == MC_NO_VALUE:
return
env_attr = self._mc_attributes.get(attr_name)
if env_attr is None:
env_attr = _McAttribute()
self._mc_attributes[attr_name] = env_attr
old_value = MC_NO_VALUE
else:
old_value = env_attr.env_values.get(current_env, MC_NO_VALUE)
if mc_set_unknown and old_value != MC_NO_VALUE:
msg = "Attempting to use 'mc_set_unknown' to overwrite a an existing @property '{attr_name}'.".format(attr_name=attr_name)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
self._mc_setattr_env_value(current_env, attr_name, env_attr, value, old_value, from_eg, mc_force, mc_error_info_up_level + 1, mc_5_migration)
return
if isinstance(cls_attr, RepeatableDict):
msg = "'{name}' is already defined as a nested-repeatable and may not be replaced with an attribute.".format(name=attr_name)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
if not mc_overwrite_property:
base_msg = "The attribute '{name}' clashes with a @property or method".format(name=attr_name)
msg = base_msg + " and 'mc_overwrite_property' is False."
if is_assign:
msg = base_msg + ". Use item.setattr with mc_overwrite_property=True if overwrite intended."
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
if not isinstance(cls_attr, property):
msg = "'mc_overwrite_property' specified but existing attribute '{name}' with value '{value}' is not a @property.".format(
name=attr_name, value=cls_attr)
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
# Now we know we had a @property at class level
if value == MC_NO_VALUE:
# No value was give for current env, so no need to do anything, we will fall back to the @property
return
# Replace property with a wrapper
setattr(self.__class__, attr_name, _McPropertyWrapper(attr_name, cls_attr))
env_attr = _McAttribute()
self._mc_attributes[attr_name] = env_attr
self._mc_setattr_env_value(current_env, attr_name, env_attr, value, MC_NO_VALUE, from_eg, mc_force, mc_error_info_up_level + 1, mc_5_migration)
return
def _mc_setattr_disabled(
self, current_env, attr_name, value, from_eg, mc_overwrite_property, mc_set_unknown, mc_force, mc_error_info_up_level,
mc_5_migration=False, is_assign=False):
"""Common code for assignment and item.setattr to disable attribute modification after config is loaded"""
msg = "Trying to set attribute '{}'. Setting attributes is not allowed after configuration is loaded or while doing json dump (print) (in order to enforce derived value validity)."
raise ConfigApiException(msg.format(attr_name))
_mc_setattr_real = _mc_setattr # Keep a reference to the real _mc_setattr
def __setattr__(self, attr_name, value):
if attr_name[0] == '_':
object.__setattr__(self, attr_name, value)
return
cr = self._mc_root
self._mc_setattr(
thread_local.env, attr_name, value, cr.env_factory.default, False, False, False, mc_error_info_up_level=3,
mc_5_migration=cr._mc_5_migration, is_assign=True)
def setattr(self, attr_name, mc_overwrite_property=False, mc_set_unknown=False, mc_force=False, mc_error_info_up_level=2, **env_values):
"""Set env specific values for an attribute.
Arguments:
attr_name (str): The name of the attribute to set.
mc_overwrite_property (bool=False): Setting this to True allows overwriting a @property method with env specific values.
Any env for which the @property is not overridden will still get the value of the @property method.
mc_set_unknown (bool=False): This allows setting a property which was not defined in the __init__ method.
mc_force (bool=False): Force the value of the property regardless of the normal multiconf rules for assigning values.
This should be used with care, as normal validation is disabled. Using this could be a sign of bad configuration/modelling.
mc_error_info_up_level (int): Only for use if a class overrides setattr. You must add 1 each time it is overridden.
This is used for calculating the file:line info in case of errors.
**env_values (dict[env-name]->value): The env specific values to assign. Arg names must be valid env names from the EnvFactory used to
create the configuration.
"""
if attr_name[0] == '_':
msg = "Trying to set attribute '{}' on a config item. ".format(attr_name)
msg += ("Atributes starting with '_mc' are reserved for multiconf internal usage." if attr_name.startswith('_mc') else
"Atributes starting with '_' cannot be set using item.setattr. Use assignment instead.")
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
if not env_values:
msg = "No Env or EnvGroup names specified."
self._mc_print_error_caller(msg, mc_error_info_up_level)
return
cr = self._mc_root
env_factory = cr.env_factory
if cr._mc_check_unknown:
# Check that there are no undefined eg names specified
undefined = []
for eg_name in env_values:
try:
env_factory.env_or_group_from_name(eg_name)
except EnvException:
undefined.append(eg_name)
if undefined:
msg = "No such Env or EnvGroup: " + repr(undefined[0]) # TODO list
self._mc_print_error_caller(msg, mc_error_info_up_level)
current_env = thread_local.env
try:
value, eg = env_factory._mc_resolve_env_group_value(current_env, env_values)
self._mc_setattr(
current_env, attr_name, value, eg, mc_overwrite_property, mc_set_unknown, mc_force, mc_error_info_up_level + 1, cr._mc_5_migration)
return
except MissingValueEnvException:
self._mc_setattr(
current_env, attr_name, MC_NO_VALUE, env_factory.eg_none, mc_overwrite_property, mc_set_unknown, False, mc_error_info_up_level + 1, cr._mc_5_migration)
return
except AmbiguousEnvException as ex:
msg = "Value for {env} is specified more than once, with no single most specific group or direct env:".format(env=current_env)
for eg in ex.ambiguous:
value = env_values[eg.name]
msg += "\nvalue: " + repr(value) + ", from: " + repr(eg)
self._mc_print_error_caller(msg, mc_error_info_up_level)
def getattr(self, attr_name, env):
"""Get the attribute value for the specified env.
Arguments:
attr_name (str): The attribute name.
env (Env): The env to get the value for.
"""
try:
orig_env = thread_local.env
thread_local.env = env
return getattr(self, attr_name)
finally:
thread_local.env = orig_env
def attr_env_items(self, attr_name, ignored_exceptions=()):
"""Iterate through the attribute (env, value) for the all defined envs.
If ConfigExcludedAttributeError, ConfigExcludedKeyError or any exception specified in `ignored_exceptions` is raised then
`McInvalidValue.MC_NO_VALUE` is returned.
Arguments:
attr_name (str): The attribute name.
ignored_exceptions (type or sequence(type)): Additional exception classes to ignore. This can be necessary when
`attr_name` references a @property method which may raise an arbitrary error when called for an env where some of
it's dependencies may not be setup correctly.
Yields:
env (Env), value (any): The (env, attribute value) for each env or `MC_NO_VALUE` is there is no value for a specific
env (e.g. the item is excluded). If an exception was raised for all envs the last exception will propagate.
"""
try:
exception = True
orig_env = thread_local.env
# print("attr_env_items 1:", attr_name, 'current env:', orig_env, bool(self))
for env in self._mc_root._mc_env_factory.envs.values():
thread_local.env = env
# print("attr_env_items 2:", env, type(self), bool(self),
# '\n self._mc_handled_env_bits', int_to_bin_str(self._mc_handled_env_bits),
# '\n env.mask ', int_to_bin_str(env.mask))
try:
yield env, getattr(self, attr_name)
exception = False
except (ConfigExcludedAttributeError, ConfigExcludedKeyError) as ex:
# print("attr_env_items 3:", ex)
if exception:
exception = ex
yield env, MC_NO_VALUE
except ignored_exceptions as ex:
# print("attr_env_items 4:", repr(ex), 'hello')
if exception:
exception = ex
yield env, MC_NO_VALUE
finally:
thread_local.env = orig_env
if exception and exception is not True:
raise exception
def attr_env_values(self, attr_name, ignored_exceptions=()):
"""Iterate through the attribute value for the all defined envs.
See :meth:`attr_env_items` for common behaviour.
Yields:
value (any): The attribute value for each env.
"""
for _, value in self.attr_env_items(attr_name, ignored_exceptions):
yield value
def env_loop(self):
"""Iterator over all defined envs.
Sets current env and yields it.
This is most useful for cross env applications where the config has been instantiated with `MC_NO_ENV`.
E.g.::
class item(ConfigItem):
def __init__(self, aa):
super(item, self).__init__()
self.aa = aa
self.aa_alternate = MC_REQUIRED
@property
def aa_special(self):
return self.aa_alternate + self.aa
@mc_config(ef)
def config(root):
with item(aa=1) as it:
it.setattr('aa_alternate', default=1, prod=7)
cr = config(MC_NO_ENV)
exp_envs = [pp, prod]
exp_values = [2, 8]
for index, env in enumerate(cr.item.env_loop()):
print(cr.item.aa)
print(cr.item.aa_special)
prints: 1 2 1 8
Yields:
env (Env): The env which was set as the current env.
"""
try:
orig_env = thread_local.env
for env in self._mc_root._mc_env_factory.envs.values():
thread_local.env = env
yield env
finally:
thread_local.env = orig_env
def items(self):
"""Iterate all nested items.
Yields:
item (ConfigItem or RepeatableDict): Nested items.
"""
for key, item in self._mc_items.items():
if not item or isinstance(item, _ConfigBuilder):
continue
yield key, item
@property
def env(self):
return thread_local.env
@property
def env_factory(self):
return self._mc_root._mc_env_factory
@property
def root_conf(self):
return self._mc_root
@property
def contained_in(self):
mc_contained_in = self._mc_contained_in
child = self
while isinstance(mc_contained_in, _ConfigBuilder):
if mc_contained_in._mc_where == Where.IN_WITH and not child._mc_where == Where.IN_MC_BUILD:
msg = "Use of 'contained_in' in not allowed in object while under the 'with' statement of a ConfigBuilder. The final containment is still unknown."
self._mc_print_error_caller(msg, mc_error_info_up_level=2)
raise ConfigApiException(msg)
if self._mc_root._mc_config_post_validated and not isinstance(child, _ItemParentProxy):
msg = "Use of 'contained_in' in not allowed through direct reference to an item from 'with' statement of a ConfigBuilder. Containment is unknown."
self._mc_print_error_caller_unchecked(msg, mc_error_info_up_level=2)
raise ConfigApiException(msg)
mc_contained_in = mc_contained_in._mc_contained_in
child = child._mc_contained_in
return mc_contained_in
def find_contained_in_or_none(self, named_as):
"""Find first parent container named as 'named_as', by searching backwards towards root_conf, starting with parent container"""
contained_in = self.contained_in
while contained_in:
if contained_in.named_as() == named_as:
return contained_in
contained_in = contained_in.contained_in
return None
def find_contained_in(self, named_as):
"""Find first parent container named as 'named_as', by searching backwards towards root_conf, starting with parent container"""
contained_in = self.contained_in
while contained_in:
if contained_in.named_as() == named_as:
return contained_in
contained_in = contained_in.contained_in
# Error, create error message
contained_in = self.contained_in
contained_in_names = []
while contained_in:
contained_in_names.append(contained_in.named_as())
contained_in = contained_in.contained_in
msg = ': Could not find a parent container named as: ' + repr(named_as) + ' in hieracy with names: ' + repr(contained_in_names)
raise ConfigException("Searching from: " + repr(type(self)) + msg)
def find_attribute_or_none(self, name):
"""Find first occurrence of attribute or child item 'name', by searching backwards towards root_conf, starting with self."""
contained_in = self
while contained_in:
attr = contained_in._mc_attributes.get(name)
if attr:
return getattr(contained_in, name)
item = contained_in._mc_items.get(name)
if item:
return item
contained_in = contained_in.contained_in
return None
def find_attribute(self, name):
"""Find first occurrence of attribute or child item 'name', by searching backwards towards root_conf, starting with self."""
contained_in = self
while contained_in:
attr = contained_in._mc_attributes.get(name)
if attr:
return getattr(contained_in, name)
item = contained_in._mc_items.get(name)
if item:
return item
contained_in = contained_in.contained_in
# Error, create error message
contained_in = self
contained_in_names = []
while contained_in:
contained_in_names.append(contained_in.named_as())
contained_in = contained_in.contained_in
msg = ': Could not find an attribute named: ' + repr(name) + ' in hieracy with names: ' + repr(contained_in_names)
raise ConfigException("Searching from: " + repr(type(self)) + msg)
class AbstractConfigItem(_ConfigBase):
"""This may be used as the base of classes which will be basis for both Repeatable and non-repeatable ConfigItem.
Note: This is an Abstract class even though it it not Abstract in the Python sense, because of the complexity of maintaining Python 2 and 3
compatibility with abstract classes.
Inheriting from this class makes it possible to use the decorators on a your base class and then later in the hierarchy split into Repeatable and
non repeatable.
"""
def __new__(cls, mc_key=None, *init_args, **init_kwargs):
try:
object.__getattribute__(cls, '_mc_cls_dir_entries')
except AttributeError:
# Get dir list before attributes are added, but attributes may have been added to a base class, so filter those out
# Assume that dir(cls) will never fail
cls._mc_cls_dir_entries = [dd for dd in dir(cls) if not isinstance(getattr(cls, dd), _McAttributeAccessor)]
return super(AbstractConfigItem, cls).__new__(cls)
def __init__(self, mc_key=None, mc_include=None, mc_exclude=None):
previous_item = _ConfigBase._mc_last_item
try:
self._mc_freeze_previous(mc_error_info_up_level=None)
except Exception as ex:
print("Exception validating previously defined object -", file=sys.stderr)
print(" type:", type(_ConfigBase._mc_last_item or previous_item), file=sys.stderr)
print("Stack trace will be misleading!", file=sys.stderr)
print("This happens if there is an error (e.g. attributes with value MC_REQUIRED or missing '@required' ConfigItems) in", file=sys.stderr)
print("an object that was not directly enclosed in a with statement. Objects that are not arguments to a with", file=sys.stderr)
print("statement will not be validated until the next ConfigItem is declared or an outer with statement is exited.", file=sys.stderr)
raise
_ConfigBase._mc_last_item = self
if not self._mc_contained_in:
self._mc_handled_env_bits &= ~thread_local.env.mask
raise _McExcludedException()
if mc_include or mc_exclude:
self._mc_select_envs(mc_include, mc_exclude)
def _mc_select_envs(self, include, exclude):
"""Calculate whether to include or exclude item in env."""
try:
selected = self._mc_root._mc_env_factory._mc_select_env_list(self.env, exclude or [], include or [])
except AmbiguousEnvException as ex:
msg = "{env} is specified in both include and exclude, with no single most specific group or direct env:"
msg += "\n - from exclude: {egx}"
msg += "\n - from include: {egi}"
ex = ConfigException(msg.format(env=self.env, egx=ex.ambiguous[0], egi=ex.ambiguous[1]))
ex.__suppress_context__ = True
raise ex
if selected == 1 or (selected is None and include):
self._mc_handled_env_bits &= ~thread_local.env.mask
return True
return False
def mc_select_envs(self, include=None, exclude=None, mc_error_info_up_level=2):
"""Calculate whether item should be included or excluded.
This should be the first statement in the 'with' block
If item is excluded, then the 'with' block, is skipped and no multiconf validations are done for item or contained items.
Arguments:
include (list[env]): List of Envs/EngGroups for which to include this item (and contained items)
exclude (list[env]): List of Envs/EngGroups for which to exclude this item (and contained items)
mc_error_info_up_level (int): Only for use if a class overrides mc_select_envs. You must add 1 each time it is overridden.
This is used for calculating the file:line in case of ambiguous include/exclude lists.
The inclusion/exclusion is done on a 'most specific' basis -
- If an item is excluded by an EnvGroup specification but included by a more specific EnvGroup (or Env), then it will be included.
- If an item is included by an EnvGroup specification but excluded by a more specific EnvGroup (or Env), then it will be excluded.
"""
try:
if self._mc_select_envs(include, exclude):
raise _McExcludedException()
except ConfigException as ex:
self._mc_print_error_caller(str(ex), mc_error_info_up_level)
def _mc_get_repeatable(self, repeatable_class_key, repeatable_cls_or_dict):
"""Return repeatable if item has repeatable with 'repeatable_class_key', if not raise an exception."""
if repeatable_class_key in self.__class__._mc_deco_nested_repeatables:
return object.__getattribute__(self, repeatable_class_key)
if isinstance(repeatable_cls_or_dict, RepeatableDict):
# Get class of first item for error message. TODO: muliple types can be in the same repeatable
for item in repeatable_cls_or_dict._all_items.values(): # pragma: no branch
repeatable_cls_or_dict = type(item)
break
msg = not_repeatable_in_parent_msg.format(
repeatable_cls_key=repeatable_class_key, repeatable_cls=repeatable_cls_or_dict, ci_named_as=self.named_as(), ci_cls=type(self))
raise ConfigException(msg)
[docs]class ConfigItem(AbstractConfigItem):
"""Base class for config items."""
def __new__(cls, *init_args, **init_kwargs):
# cls._mc_debug_hierarchy('ConfigItem.__new__')
contained_in = cls._mc_hierarchy[-1]
built_by = None
# Find the first parent which is not a builder if we are in the mc_build method of a builder
if contained_in._mc_where == Where.IN_MC_BUILD:
built_by = contained_in
while contained_in._mc_where == Where.IN_MC_BUILD:
contained_in = contained_in._mc_contained_in
name = cls.named_as()
try:
self = object.__getattribute__(contained_in, name)
if self._mc_handled_env_bits & thread_local.env.mask:
# We are trying to replace a non-repeatable object. In mc_init we ignore this.
if contained_in._mc_where == Where.IN_MC_INIT:
self._mc_where = Where.IN_RE_INIT
return self
raise ConfigException("Repeated non repeatable conf item: '{name}': {cls}".format(name=name, cls=cls))
self._mc_handled_env_bits |= thread_local.env.mask
self._mc_where = Where.IN_INIT
self._mc_num_errors = 0
return self
except AttributeError:
self = super(ConfigItem, cls).__new__(cls)
self._mc_where = Where.IN_INIT
self._mc_num_errors = 0
self._mc_attributes = OrderedDict()
self._mc_attributes_to_check = None
self._mc_items = OrderedDict()
self._mc_contained_in = contained_in
self._mc_root = contained_in._mc_root
self._mc_built_by = built_by
self._mc_handled_env_bits = thread_local.env.mask
for key in cls._mc_deco_nested_repeatables:
od = RepeatableDict()
self._mc_items[key] = od # Needed to implement reliable 'items' method
object.__setattr__(self, key, od)
# Insert self in parent
if name in contained_in.__class__._mc_deco_nested_repeatables:
msg = repeatable_in_parent_msg.format(named_as=name, cls=cls, ci_item=contained_in)
raise ConfigException(msg, is_fatal=True)
if name in contained_in._mc_attributes:
msg = "'{name}' is defined both as simple value and a contained item: {self}".format(name=name, self=self)
raise ConfigException(msg, is_fatal=True)
object.__setattr__(contained_in, name, self)
contained_in._mc_items[name] = self # Needed to implement reliable 'items' method
return self
def __init__(self, mc_include=None, mc_exclude=None):
super(ConfigItem, self).__init__(mc_include=mc_include, mc_exclude=mc_exclude)
[docs]class RepeatableConfigItem(AbstractConfigItem):
"""Base class for config items which may be repeated.
RepeatableConfigItems will be stored in an OrderedDict using the key 'mc_key'.
Args:
mc_key (hashable): The key used to lookup the config item.
"""
_mc_key_name = None
_mc_key_value = None
def __new__(cls, mc_key=None, *init_args, **init_kwargs):
# cls._mc_debug_hierarchy('RepeatableConfigItem.__new__')
contained_in = cls._mc_hierarchy[-1]
built_by = None
# Find the first parent which is not a builder if we are in the mc_build method of a builder
if contained_in._mc_where == Where.IN_MC_BUILD:
built_by = contained_in
while contained_in._mc_where == Where.IN_MC_BUILD:
contained_in = contained_in._mc_contained_in
repeatable = contained_in._mc_get_repeatable(cls.named_as(), cls)
mc_key = init_kwargs.get(cls._mc_key_name) or cls._mc_key_value or mc_key
try:
self = repeatable._all_items[mc_key]
if self._mc_handled_env_bits & thread_local.env.mask:
# We are trying to replace an object with the same mc_key. In mc_init we ignore this.
if contained_in._mc_where == Where.IN_MC_INIT:
self._mc_where = Where.IN_RE_INIT
return self
build_msg = " from 'mc_build'" if built_by else ""
raise ConfigException("Re-used key '{key}' in repeated item {cls}{build_msg} overwrites existing entry in parent:\n{ci}".format(
key=mc_key, cls=cls, build_msg=build_msg, ci=contained_in))
self._mc_handled_env_bits |= thread_local.env.mask
self._mc_where = Where.IN_INIT
self._mc_num_errors = 0
return self
except KeyError:
self = super(RepeatableConfigItem, cls).__new__(cls)
self._mc_where = Where.IN_INIT
self._mc_num_errors = 0
self._mc_attributes = OrderedDict()
self._mc_attributes_to_check = None
self._mc_items = OrderedDict()
self._mc_contained_in = contained_in
self._mc_root = contained_in._mc_root
self._mc_built_by = built_by
self._mc_handled_env_bits = thread_local.env.mask
for key in cls._mc_deco_nested_repeatables:
od = RepeatableDict()
self._mc_items[key] = od # Needed to implement reliable 'items' method
object.__setattr__(self, key, od)
# Insert self in repeatable
repeatable._all_items[mc_key] = self
return self
[docs] @classmethod
def named_as(cls):
"""Return the named_as property set by the @named_as decorator"""
return cls._mc_deco_named_as or (cls.__name__ + 's')
class _ConfigBuilder(AbstractConfigItem):
"""Base class for 'builder' items which can create (a collection of) other items."""
def __new__(cls, mc_key='default-builder', *init_args, **init_kwargs):
# cls._mc_debug_hierarchy('_ConfigBuilder.__new__')
contained_in = cls._mc_hierarchy[-1]
built_by = None
# Find the first parent which is not a builder if we are in the mc_build method of a builder
if contained_in._mc_where == Where.IN_MC_BUILD:
built_by = contained_in
while contained_in._mc_where == Where.IN_MC_BUILD:
contained_in = contained_in._mc_contained_in
private_key = cls.named_as() + ' ' + str(mc_key)
try:
self = contained_in._mc_items[private_key]
if self._mc_handled_env_bits & thread_local.env.mask:
# We are trying to replace an object with the same mc_key. In mc_init we ignore this.
if contained_in._mc_where == Where.IN_MC_INIT:
self._mc_where = Where.IN_RE_INIT
return self
build_msg = " from 'mc_build'" if built_by else ""
raise ConfigException("Re-used key '{key}' in repeated item {cls}{build_msg} overwrites existing entry in parent:\n{ci}".format(
key=mc_key, cls=cls, build_msg=build_msg, ci=contained_in))
self._mc_handled_env_bits |= thread_local.env.mask
self._mc_where = Where.IN_INIT
self._mc_num_errors = 0
return self
except KeyError:
self = super(_ConfigBuilder, cls).__new__(cls)
self._mc_where = Where.IN_INIT
self._mc_num_errors = 0
self._mc_attributes = OrderedDict()
self._mc_attributes_to_check = None
self._mc_items = OrderedDict()
self._mc_contained_in = contained_in
self._mc_root = contained_in._mc_root
self._mc_built_by = built_by
self._mc_handled_env_bits = thread_local.env.mask
contained_in._mc_items[private_key] = self
return self
def __init__(self, mc_key='default-builder', mc_include=None, mc_exclude=None):
# Overridden to accept 'mc_key'
super(_ConfigBuilder, self).__init__(mc_include=mc_include, mc_exclude=mc_exclude)
@classmethod
def named_as(cls):
"""Try to generate a unique name"""
return '_mc_ConfigBuilder_' + cls.__name__
def _mc_get_repeatable(self, repeatable_class_key, repeatable_cls_or_dict):
"""ConfigBuilder allows any nested repeatable without previous declaration."""
repeatable = getattr(self, repeatable_class_key, None)
if repeatable is not None:
return repeatable
repeatable = RepeatableDict()
self._mc_items[repeatable_class_key] = repeatable
object.__setattr__(self, repeatable_class_key, repeatable)
return repeatable
def _mc_builder_freeze(self):
self._mc_where = Where.IN_MC_BUILD
_ConfigBase._mc_last_item = None
try:
self.mc_build()
except _McExcludedException:
pass
def insert(from_build, from_with_key, from_with):
"""Insert items from with statement (single or repeatable) in a single (non repeatable) item from mc_build."""
if from_build._mc_built_by is not self:
return
if isinstance(from_with, RepeatableDict):
repeatable = from_build._mc_get_repeatable(from_with_key, from_with)
for wi_key, wi in from_with._all_items.items():
pp = _ItemParentProxy(from_build, wi)
repeatable._all_items[wi_key] = pp
return
pp = _ItemParentProxy(from_build, from_with)
from_build._mc_items[from_with_key] = pp
object.__setattr__(from_build, from_with_key, pp)
# Now set all items created in the 'with' block of the builder on the items created in the 'mc_build' method
for item_from_with_key, item_from_with in self.items():
for item_from_build_key, item_from_build in self._mc_contained_in.items():
if isinstance(item_from_build, RepeatableDict):
for bi_key, bi in item_from_build._all_items.items():
insert(bi, item_from_with_key, item_from_with)
continue
continue
insert(item_from_build, item_from_with_key, item_from_with)
self._mc_freeze_previous(mc_error_info_up_level=1)
self._mc_where = Where.NOWHERE
class _ItemParentProxy(object):
"""The purpose of this is to set the current '_mc_contained_in' when accessing an item created by a builder and assigned under multiple parent items"""
__slots__ = ('_mc_contained_in', '_mc_proxied_item')
_mc_lock = threading.RLock()
def __init__(self, ci, item):
object.__setattr__(self, '_mc_contained_in', ci)
object.__setattr__(self, '_mc_proxied_item', item)
def __getattribute__(self, name):
if name in object.__getattribute__(self, '__slots__'):
return object.__getattribute__(self, name)
item = object.__getattribute__(self, '_mc_proxied_item')
_ItemParentProxy._mc_lock.acquire()
orig_ci = item._mc_contained_in
item._mc_contained_in = object.__getattribute__(self, '_mc_contained_in')
try:
return getattr(item, name)
finally:
item._mc_contained_in = orig_ci
_ItemParentProxy._mc_lock.release()
def __setattr__(self, attr_name, value):
if attr_name[0] == '_':
object.__setattr__(self._mc_proxied_item, attr_name, value)
return
cr = self._mc_proxied_item._mc_root
self._mc_proxied_item._mc_setattr(
thread_local.env, attr_name, value, cr.env_factory.default, False, False, False, mc_error_info_up_level=3,
mc_5_migration=cr._mc_5_migration, is_assign=True)
def __bool__(self):
return self._mc_contained_in.__bool__() and self._mc_proxied_item.__bool__()
# Python2 compatibility
__nonzero__ = __bool__
class _ConfigRoot(_ConfigBase):
_mc_cls_dir_entries = ()
def __init__(self, env_factory, mc_todo_handling_other, mc_todo_handling_allowed, mc_json_filter, mc_json_fallback, mc_do_type_check, mc_5_migration):
self._mc_env_factory = env_factory
self._mc_todo_handling_other = mc_todo_handling_other
self._mc_todo_handling_allowed = mc_todo_handling_allowed
self._mc_json_filter = mc_json_filter
self._mc_json_fallback = mc_json_fallback
self._mc_do_type_check = mc_do_type_check
self._mc_5_migration = mc_5_migration
self._mc_where = Where.IN_INIT
self._mc_num_errors = 0
self._mc_todo_msgs = OrderedDict([(env, []) for env in env_factory.envs.values()])
self._mc_attributes = OrderedDict()
self._mc_attributes_to_check = None
self._mc_items = OrderedDict()
self._mc_contained_in = None
self._mc_root = self
self._mc_handled_env_bits = 0
self._mc_num_warnings = 0
self._mc_config_result = {}
self._mc_config_loaded = False
self._mc_in_post_validate = False
self._mc_config_post_validated = False
self._mc_num_property_errors = 0
self._mc_num_invalid_property_usage = 0
self._mc_in_json = False
@property
def mc_config_result(self):
return self._mc_config_result[self.env]
def __bool__(self):
return True
__nonzero__ = __bool__
class _RootEnvProxy(object):
"""The purpose of this is to set the current env when accessing a configuration"""
__slots__ = ('_mc_root', '_mc_env')
def __init__(self, env, root_item):
thread_local.env = env
object.__setattr__(self, '_mc_env', env)
object.__setattr__(self, '_mc_root', root_item)
def __getattr__(self, name):
cr = self._mc_root
thread_local.env = self._mc_env
return getattr(cr, name)
@property
def env(self):
return self._mc_env
def __repr__(self):
return repr(self._mc_root)
[docs]def mc_config(
env_factory, error_next_env=False, validate_properties=True,
mc_todo_handling_other=McTodoHandling.ERROR, mc_todo_handling_allowed=McTodoHandling.WARNING,
mc_json_filter=None, mc_json_fallback=None, do_type_check=None, do_post_validate=True, lazy_load=False, mc_5_migration=False):
"""Function decorator for instantiating ConfigItem hierarchy for all Envs defined in 'env_factory'.
This decorator creates a wrapped config function which is then used for retrieving the configuration for a specific env.
The wrapped function signature is:
Arguments:
env (Env): The environment for which to retrieve the config.
allow_todo (bool): If true, then retrieving a configuration for an env which contains `MC_TODO` values will not raise an error.
Return (Root ConfigItem proxy): Reference to the config with the current env set to env.
E.g.::
@mc_config(envf)
def conf(root):
with someitem() as it:
it.setattr('aa', default=1, tst=2, prod=3)
# Get the cfg instantiated for 'prod'
prod_cfg = conf(prod)
NOTE, There can only be one current config!
It is possible to instantiate the config multiple times, but storing references to items in the configuration, and accessing attributes
at a later time, will return the value from the last env.
Arguments:
env_factory (EnvFactory): The EnvFactory defining the envs for which we instantiate the configuration.
error_next_env (bool): If this is False, then no more envs will be instantiated after errors are found in an env.
If True, then instantiation is attempted for all envs, but an exception is raised at the end in any envs could not
be instantiated.
mc_todo_handling_other (McTodoHandling): This specifies how to handle attributes set to MC_TODO for envs with 'allow_todo' False.
The default is McTodoHandling.ERROR, causing an error message to be printed and the configuration to be considered invalid.
mc_todo_handling_allowed (McTodoHandling): This specifies how to handle attributes set to MC_TODO for envs with 'allow_todo' True.
The default is McTodoHandling.WARNING, causing a warning message to be printed but the configuration to be considered valid.
mc_json_filter (func(obj, key, value)): User defined function for filtering objects in json output.
- filter_callable is called for each key/value pair of attributes on each ConfigItem obj.
- It must return a tuple of (key, value). If key is False, the key/value pair is removed from the json output
mc_json_fallback (func(obj)): User defined function for handling objects not otherwise encoded in json output.
- fallback_callable is called for objects that are not handled by the builtin encoder.
- It must return a tuple (object, handled). If handled is True, the object must be encodable by the standard json encoder.
do_type_check (bool): Do type checking of attributes based on typing annotations. Default is True for Python 3.6.1+. Attempting
to enable this for earlier Python versions will raise an exception.
Type checking of attributes is done based on typing information from the __init__ signature. If an attribute exists with the same
name as an __init__ argument with typing information, then the attribute must conform to that type. E.g.::
class X(ConfigItem):
def __init__(self, a:int = MC_REQUIRED):
super(X).__init__()
self.a = a
It will be checked that x.a is instance of int.
do_post_validate (bool): Allow skipping the mc_post_validate call. I.e. if set to False the user defined call backs are not called.
lazy_load (bool): Allow loading config only for envs for which is instantiated by calling the wrapped config method. If False the config is
pre-instantiated for all envs in order to validate correctness of the configuration for all envs. Enabling lazy_load also disables
`mc_post_validate` calls and other checking which cannot be done with lazy loading.
mc_5_migration (bool): This changes the attribute overwriting rule to me more compatible with version 5. Do not use this in any new configurations.
"""
if not isinstance(env_factory, EnvFactory):
msg = "'env_factory' arg must be instance of {ef_typ!r}; found type {got_typ!r}: {val!r}"
raise ConfigException(msg.format(ef_typ=EnvFactory.__name__, got_typ=env_factory.__class__.__name__, val=env_factory))
for _ in env_factory.envs:
# There is at least one env
break
else:
raise ConfigException("The specified 'env_factory' is empty. It must have at least one Env.")
if not isinstance(mc_todo_handling_other, McTodoHandling):
msg = "'mc_todo_handling_other' arg must be instance of {th_typ!r}; found type {got_typ!r}: {val!r}"
raise ConfigException(msg.format(th_typ=McTodoHandling.__name__, got_typ=mc_todo_handling_other.__class__.__name__, val=mc_todo_handling_other))
if not isinstance(mc_todo_handling_allowed, McTodoHandling):
msg = "'mc_todo_handling_allowed' arg must be instance of {th_typ!r}; found type {got_typ!r}: {val!r}"
raise ConfigException(msg.format(th_typ=McTodoHandling.__name__, got_typ=mc_todo_handling_allowed.__class__.__name__, val=mc_todo_handling_allowed))
allow_type_check = major_version >= 3 and typecheck.typing_vcheck()
if do_type_check:
if not allow_type_check:
raise ConfigException(typecheck.unsup_version_msg)
else:
do_type_check = do_type_check is None and allow_type_check
def load_one_env(env, conf_func, cr, root_proxies, error_envs):
_mc_debug("\n==== Loading", env, "====")
rp = _RootEnvProxy(env, cr)
thread_local.env = env
del cr.__class__._mc_hierarchy[:]
_ConfigBase._mc_last_item = None
try:
with cr:
res = conf_func(cr)
cr._mc_handled_env_bits |= env.mask
cr._mc_call_mc_validate_recursively(env)
if validate_properties:
_mc_debug("\n==== Validating @properties", env, "====")
cr._mc_validate_properties_recursively(env)
if cr._mc_num_property_errors:
raise ConfigException("Error validating @property methods for {}".format(env))
cr._mc_check_unknown = False
cr._mc_config_result[env] = res
root_proxies[env] = rp
except ConfigException as ex:
if not error_next_env or ex.is_fatal:
raise
if not ex.is_summary:
traceback.print_exc(file=sys.stderr)
else:
print(ex.__class__.__name__ + ':', ex, file=sys.stderr)
print("Error in config for {} above.\n".format(env), file=sys.stderr)
error_envs.append(env)
def deco(conf_func):
env_factory._mc_calc_env_group_order()
# Create root object
cr = _ConfigRoot(env_factory, mc_todo_handling_other, mc_todo_handling_allowed, mc_json_filter, mc_json_fallback, do_type_check, mc_5_migration)
cr._mc_check_unknown = True
# Make sure _mc_setattr is the real one if decorator is used multiple times
_ConfigBase._mc_setattr = _ConfigBase._mc_setattr_real
# Load envs
root_proxies = {}
error_envs = []
if not lazy_load:
root_proxies[MC_NO_ENV] = cr
for env in env_factory.envs.values():
load_one_env(env, conf_func, cr, root_proxies, error_envs)
if error_envs:
raise ConfigException("The following envs had errors {}".format(error_envs))
# No modifications are allowed after this
cr._mc_config_loaded = True
_ConfigBase._mc_setattr = _ConfigBase._mc_setattr_disabled
if do_post_validate:
cr._mc_in_post_validate = True
# Call mc_post_validate
thread_local.env = MC_NO_ENV
_mc_debug("\n==== Calling 'mc_post_validate' ====")
cr._mc_call_mc_post_validate_recursively()
cr._mc_in_post_validate = False
cr._mc_config_post_validated = True
def config_wrapper(env, allow_todo=False):
try:
rp = root_proxies[env]
except KeyError:
if not isinstance(env, Env):
msg = "{ef_cls}: env must be instance of {env_cls!r}; found type '{got_typ}': {val!r}"
raise ConfigException(msg.format(ef_cls=env_factory.__class__.__name__, env_cls=Env.__name__, got_typ=type(env).__name__, val=env))
if lazy_load and env is MC_NO_ENV:
raise ConfigException("{} cannot be used with 'lazy_load'.".format(env))
if env.factory != env_factory:
raise ConfigException("The selected env {} must be from the 'env_factory' specified for 'mc_config'.".format(env))
if lazy_load:
cr._mc_check_unknown = True
# Make sure _mc_setattr is the real one if decorator is used multiple times
_ConfigBase._mc_setattr = _ConfigBase._mc_setattr_real
load_one_env(env, conf_func, cr, root_proxies, error_envs)
rp = _RootEnvProxy(env, cr)
else:
raise # Should not happen
if env is not MC_NO_ENV and not allow_todo and rp._mc_todo_msgs[env]:
for msg, fname, line in rp._mc_todo_msgs[env]:
print(_line_msg(file_name=fname, line_num=line), file=sys.stderr)
print(msg, file=sys.stderr)
raise ConfigException("Trying to get invalid configuration containing MC_TODO")
return rp
return config_wrapper
return deco