#
# Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
# Copyright (C) 2018-2020 OpenCyphal Development Team <opencyphal.org>
# This software is distributed under the terms of the MIT License.
#
"""Logic for parsing language configuration.
"""
import re
import types
import typing
from yaml import Loader as YamlLoader
from yaml import load as yaml_loader
from nunavut._utilities import deep_update
[docs]class LanguageConfig:
"""
Configuration storage encapsulating parsers and other configuration format details. For any configuration type used
the concept of "sections" must be maintained which requires that the top-level configuration be structured as
key/value pairs with the keys using the form "nunavut.lang.[language name]". For example, yaml configuration must
have a top-level structure like this:
.. code-block:: python
example_yaml = '''
nunavut.lang.a:
key_one: value_one
key_two: value_two
nunavut.lang.b:
key_one: value_one
key_two: value_two
nunavut.lang.c:
key_one: value_one
key_two: value_two
'''
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
config = LanguageConfig()
config.update_from_string(example_yaml)
data = config.sections()
assert len(data) == 3
assert data['nunavut.lang.b']['key_two'] == 'value_two'
.. note::
The "language name" part of the section identifier must not start with a number and can contain only
alphanumeric characters. That is, the section identifier must match this pattern:
nunavut\\.lang\\.[a-zA-Z]{1}\\w*
The values of the section data can be anything:
.. code-block:: python
example_yaml = '''
nunavut.lang.d:
key_one:
- is
- a
- list:
where: index2
is: a_dictionary
'''
.. invisible-code-block: python
config.update_from_string(example_yaml)
assert 'a_dictionary' == config.sections()['nunavut.lang.d']['key_one'][2]['list']['is']
"""
SECTION_NAME_PATTERN = re.compile(
r"^nunavut\.lang\.([a-zA-Z]{1}\w*)$"
) #: Required pattern for section name identifers.
def __init__(self): # type: ignore
self._sections = dict() # type: typing.Dict[str, typing.Dict[str, typing.Any]]
[docs] def update(self, configuration: typing.Any) -> None:
"""
Add configuration data to this configuration from a string.
Unlike add_section, this method will update section data with existing keys.
For example, the first update is to an empty configuration so it will act as a simple insert operation:
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
.. code-block: python
initial_data = {
'nunavut.lang.a':
{
'key_one': 'value_one',
'key_two': 'value_two'
},
'nunavut.lang.b':
{
'key_one':
[
'item_0',
{
'item_1_value_0': 0,
'item_1_value_1': 1
},
'item_2'
],
'key_two': 'value_two'
}
}
config = LanguageConfig()
config.update(initial_data)
assert config.sections()['nunavut.lang.a']['key_one'] == 'value_one'
assert config.sections()['nunavut.lang.b']['key_one'][1]['item_1_value_1'] == 1
assert config.sections()['nunavut.lang.b']['key_two'] == 'value_two'
...but updating this data is now possible where sections can be added and updated:
.. code-block: python
updated_data = '''
nunavut.lang.b:
key_one: simple
key_three: value_three
nunavut.lang.c:
key_one: new_language_key
'''
updated_data = {
'nunavut.lang.b':
{
'key_one': 'simple',
'key_three': 'value_three'
},
'nunavut.lang.c':
{
'key_one': 'new_language_key'
},
}
config.update(updated_data)
assert config.sections()['nunavut.lang.a']['key_one'] == 'value_one'
assert config.sections()['nunavut.lang.b']['key_one'] == 'simple'
assert config.sections()['nunavut.lang.b']['key_two'] == 'value_two'
assert config.sections()['nunavut.lang.b']['key_three'] == 'value_three'
assert config.sections()['nunavut.lang.c']['key_one'] == 'new_language_key'
.. invisible-code-block: python
tests = [
(
{
'did_not_start.with.nunavut':
{
'key_one': 'value_one'
}
},
ValueError()
),
(
{
'nunavut.lang.0c':
{
'key_one': 'value_one'
}
},
ValueError()
),
(
{
1:
{
'key_one': 'value_one'
}
},
TypeError()
),
(
{
'nunavut.lang.c.iso':
{
'key_one': 'value_one'
}
},
ValueError()
)
]
for test_tuple in tests:
try:
config.update(test_tuple[0])
assert False
except BaseException as e:
assert isinstance(e, type(test_tuple[1]))
pass
"""
# validate the (very loose) configuration schema.
for section_name, section_data in configuration.items():
if not isinstance(section_name, str):
raise TypeError("section names must be strings")
if not self.SECTION_NAME_PATTERN.match(section_name):
raise ValueError(
'Section name "{}" is invalid. See LanguageConfig documentation for rules.'.format(section_name)
)
self.update_section(section_name, section_data)
def update_section(self, section_name: str, configuration: typing.Any) -> None:
self._sections[section_name] = deep_update(self._sections.get(section_name, {}), configuration)
def sections(self) -> typing.Dict[str, typing.Dict[str, typing.Any]]:
return self._sections
def update_from_string(self, string: str, context: typing.Optional[str] = None) -> None:
configuration = yaml_loader(string, Loader=YamlLoader)
self.update(configuration)
def update_from_file(self, f: typing.TextIO, context: typing.Optional[str] = None) -> None:
configuration = yaml_loader(f, Loader=YamlLoader)
self.update(configuration)
def set(self, section: str, option: str, value: typing.Any) -> None:
self._sections[section][option] = value
[docs] def add_section(self, section_name: str) -> None:
"""Add a section to the configuration.
Sections are top-level containers that contain key/value pairs of configuration of a single
language type.
:param section_name: The name of the language section. This must adhere to the :data:`SECTION_NAME_PATTERN`
pattern.
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
config = LanguageConfig()
try:
config.add_section(53)
assert "add_section must throw TypeError if given non-string key."
except TypeError:
pass
try:
config.add_section("foo")
assert "add_section must throw ValueError if given an invalid string name."
except ValueError:
pass
config.add_section("nunavut.lang.c")
try:
config.add_section("nunavut.lang.c")
assert "add_section must throw ValueError if section redefinition is attempted."
except ValueError:
pass
"""
if not isinstance(section_name, str):
raise TypeError("section names must be strings")
if not self.SECTION_NAME_PATTERN.match(section_name):
raise ValueError(
'Section name "{}" is invalid. See LanguageConfig documentation for rules.'.format(section_name)
)
if section_name in self._sections:
raise ValueError("Section {} is already defined.".format(section_name))
self._sections[section_name] = dict()
_UNSET = object() # Used internally to allow "None" as a default value.
def _get_config_value_raw(self, section_name: str, key: str, default_value: typing.Any) -> typing.Any:
"""
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
.. code-block: python
test_data = {
'nunavut.lang.a':
{
'key_one': 'value_one'
},
'nunavut.lang.b':
{
'key_one': 'value_one'
}
}
config = LanguageConfig()
config.update(initial_data)
try:
config.get_config_value('nunavut.lang.c', 'foo')
assert False
except KeyError:
pass
assert 'bar' == config.get_config_value('nunavut.lang.c', 'foo', 'bar')
try:
config.get_config_value('nunavut.lang.a', 'foo')
assert False
except KeyError:
pass
assert 'bar' == config.get_config_value('nunavut.lang.a', 'foo', 'bar')
assert 'value_one' == config.get_config_value('nunavut.lang.a', 'key_one')
assert 'value_one' == config.get_config_value('nunavut.lang.a', 'key_one', 'bar')
"""
try:
section_data = self._sections[section_name]
except KeyError:
if default_value is not self._UNSET:
return default_value
else:
raise
try:
return section_data[key]
except KeyError:
if default_value is not self._UNSET:
return default_value
else:
raise
[docs] def get_config_value(self, section_name: str, key: str, default_value: typing.Optional[str] = None) -> str:
"""
Get an optional language property from the language configuration.
:param section_name : The name of the section to get the value from.
:param str key : The config value to retrieve.
:param default_value: The value to return if the key was not in the configuration. If provided this method will\
not raise.
:type default_value : typing.Optional[str]
:return: Either the value from the config or the default_value if provided.
:rtype: str
:raises: KeyError if the section or the key in the section does not exist and a default_value was not provided.
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
.. code-block: python
test_data = {
'nunavut.lang.a':
{
'key_one': [
1,
2
]
},
'nunavut.lang.b':
{
'key_one': 'value_one'
}
}
config = LanguageConfig()
config.update(test_data)
assert 'value_one' == config.get_config_value('nunavut.lang.b', 'key_one')
assert 'value_one' == config.get_config_value('nunavut.lang.b', 'key_one', 'bar')
assert 'bar' == config.get_config_value('nunavut.lang.b', 'key_two', 'bar')
try:
config.get_config_value('nunavut.lang.b', 'key_two')
assert False # supposed to throw without a default value.
except KeyError:
pass
"""
optional_result = self._get_config_value_raw(
section_name, key, (self._UNSET if default_value is None else default_value)
)
# when we've retrieved a None result the str() cast will return "None" which isn't our intent.
# Instead, if we get None and the _get_config_value_raw didn't throw a KeyError then what we really
# meant is that we wanted an empty string if the value existed but was None.
return str(optional_result) if optional_result is not None else ""
[docs] def get_config_value_as_bool(self, section_name: str, key: str, default_value: bool = False) -> bool:
"""
Get an optional language property from the language configuration returning a boolean. The rules
for boolean conversion are as follows:
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
config = LanguageConfig()
config.add_section('nunavut.lang.cpp')
.. code-block:: python
# "Any string" = True
config.set('nunavut.lang.cpp', 'v', 'Any string')
assert config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# "true" = True
config.set('nunavut.lang.cpp', 'v', 'true')
assert config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# "TrUe" = True
config.set('nunavut.lang.cpp', 'v', 'TrUe')
assert config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# "1" = True
config.set('nunavut.lang.cpp', 'v', '1')
assert config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# "false" = False
config.set('nunavut.lang.cpp', 'v', 'false')
assert not config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# "FaLse" = False
config.set('nunavut.lang.cpp', 'v', 'FaLse')
assert not config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# "0" = False
config.set('nunavut.lang.cpp', 'v', '0')
assert not config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# "" = False
config.set('nunavut.lang.cpp', 'v', '')
assert not config.get_config_value_as_bool('nunavut.lang.cpp', 'v')
# False if not defined
assert not config.get_config_value_as_bool('nunavut.lang.cpp', 'not_a_key')
# True if not defined but default_value is True
assert not config.get_config_value_as_bool('nunavut.lang.cpp', 'not_a_key')
:param section_name : The name of the section to get the value from.
:param str key : The config value to retrieve.
:param bool default_value : The value to use if no value existed.
:return : The config value as either True or False.
:rtype : bool
"""
result = self.get_config_value(section_name, key, default_value="false" if not default_value else "true")
if result.lower() == "false" or result == "0":
return False
else:
return bool(result)
[docs] def get_config_value_as_dict(
self, section_name: str, key: str, default_value: typing.Optional[typing.Dict] = None
) -> typing.Dict[str, typing.Any]:
"""
Get a language property parsing it as a map with string keys.
Example:
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
config = LanguageConfig()
config.add_section('nunavut.lang.a')
.. code-block: python
config.set('nunavut.lang.a', 'foo', {'one': 1})
assert config.get_config_value_as_dict('nunavut.lang.a', 'foo')['one'] == 1
.. invisible-code-block: python
try:
config.get_config_value_as_dict('nunavut.lang.b', 'foo')
assert False
except KeyError:
pass
assert config.get_config_value_as_dict('nunavut.lang.b', 'foo', {'one': 2})['one'] == 2
try:
config.get_config_value_as_dict('nunavut.lang.a', 'bar')
assert False
except KeyError:
pass
assert config.get_config_value_as_dict('nunavut.lang.a', 'bar', {'one': 2})['one'] == 2
config.set('nunavut.lang.a', 'bar', 1)
try:
config.get_config_value_as_dict('nunavut.lang.a', 'bar')
assert False
except TypeError:
pass
assert config.get_config_value_as_dict('nunavut.lang.a', 'bar', {'one': 2})['one'] == 2
:param str section_name : The name of the section to get the key from.
:param str key : The config value to retrieve.
:param default_value : The value to return if the key was not in the configuration. If provided this method\
will not raise a KeyError nor a TypeError.
:type default_value : typing.Optional[typing.Mapping[str, typing.Any]]
:return : Either the value from the config or the default_value if provided.
:rtype : typing.Mapping[str, typing.Any]
:raises : KeyError if the key does not exist and a default_value was not provided.
:raises : TypeError if the value exists but is not a dict and a default_value was not provided.
"""
raw_value = self._get_config_value_raw(
section_name, key, default_value=(self._UNSET if default_value is None else default_value)
)
if isinstance(raw_value, dict):
return raw_value
if default_value is None:
raise TypeError("{}.{} exists but is not a dict. (is type {})".format(section_name, key, type(raw_value)))
return default_value
[docs] def get_config_value_as_list(
self, section_name: str, key: str, default_value: typing.Optional[typing.List] = None
) -> typing.List[typing.Any]:
"""Get a language property parsing it as a map with string keys.
Example:
.. invisible-code-block: python
from nunavut.lang import LanguageConfig
config = LanguageConfig()
config.add_section('nunavut.lang.a')
.. code-block: python
config.set('nunavut.lang.a', 'foo', [1, 2, 3])
assert config.get_config_value_as_list('nunavut.lang.a', 'foo')[1] == 2
.. invisible-code-block: python
try:
config.get_config_value_as_list('nunavut.lang.b', 'foo')
assert False
except KeyError:
pass
assert config.get_config_value_as_list('nunavut.lang.b', 'foo', [2, 3, 4])[1] == 3
try:
config.get_config_value_as_list('nunavut.lang.a', 'bar')
assert False
except KeyError:
pass
assert config.get_config_value_as_list('nunavut.lang.a', 'bar', [3, 4, 5])[1] == 4
config.set('nunavut.lang.a', 'bar', 1)
try:
config.get_config_value_as_list('nunavut.lang.a', 'bar')
assert False
except TypeError:
pass
assert config.get_config_value_as_list('nunavut.lang.a', 'bar', [4, 5, 6])[1] == 5
:param str section_name : The name of the section to get the key from.
:param str key : The config value to retrieve.
:param default_value : The value to return if the key was not in the configuration. If provided this method\
will not raise a KeyError nor a TypeError.
:type default_value : typing.Optional[typing.List[typing.Any]]
:return : Either the value from the config or the default_value if provided.
:rtype : typing.List[typing.Any]
:raises : KeyError if the key does not exist and a default_value was not provided.
:raises : TypeError if the value exists but is not a dict and a default_value was not provided.
"""
raw_value = self._get_config_value_raw(
section_name, key, default_value=(self._UNSET if default_value is None else default_value)
)
if isinstance(raw_value, list):
return raw_value
if default_value is None:
raise TypeError("{}.{} exists but is not a list. (is type {})".format(section_name, key, type(raw_value)))
return default_value
# +-------------------------------------------------------------------------------------------------------------------+
# | VersionReader
# +-------------------------------------------------------------------------------------------------------------------+
class VersionReader:
"""
Helper to read an "x.y.z" semantic version from python modules as a module variable
"__version__"
"""
MODULE_VERSION_ATTRIBUTE_NAME = "__version__"
@classmethod
def parse_version(cls, version_string: str) -> typing.Optional[typing.Tuple[int, int, int]]:
version_array = [int(x) for x in version_string.split(".")]
if len(version_array) != 3:
return None
else:
return (version_array[0], version_array[1], version_array[2])
@classmethod
def read_version(cls, module: "types.ModuleType") -> typing.Tuple[int, int, int]:
version = getattr(module, cls.MODULE_VERSION_ATTRIBUTE_NAME, "0.0.0") # type: str
version_tuple = cls.parse_version(version)
if version_tuple is None:
raise RuntimeError(
'Invalid {} "{}" for module {} (expected "x.y.z")'.format(
cls.MODULE_VERSION_ATTRIBUTE_NAME, version, module.__name__
)
)
return version_tuple
def __init__(self, module_name: str):
self._module_name = module_name
self._cached = None # type: typing.Optional[typing.Tuple[int, int, int]]
@property
def version(self) -> typing.Tuple[int, int, int]:
if self._cached is None:
self._cached = self._get_version()
return self._cached
def _get_version(self) -> typing.Tuple[int, int, int]:
import importlib
try:
return self.read_version(importlib.import_module(self._module_name))
except (ImportError, ValueError):
return (0, 0, 0)