Source code for jsonargparse.util

"""Collection of general functions and classes."""

import inspect
import logging
import os
import re
import stat
import sys
import warnings
from collections import namedtuple
from contextlib import contextmanager
from contextvars import ContextVar
from functools import wraps
from types import BuiltinFunctionType, FunctionType, ModuleType
from typing import Any, Callable, Optional, Tuple, Type, TypeVar, Union

from .loaders_dumpers import load_value
from .optionals import (
    fsspec_support,
    get_config_read_mode,
    import_fsspec,
    import_reconplogger,
    import_requests,
    import_url_validator,
    reconplogger_support,
    url_support,
)
from .type_checking import ArgumentParser


__all__ = [
    'capture_parser',
    'class_from_function',
    'LoggerProperty',
    'null_logger',
    'ParserError',
    'Path',
    'register_unresolvable_import_paths',
    'usage_and_exit_error_handler',
]


logging_levels = {'CRITICAL', 'ERROR', 'WARNING', 'INFO', 'DEBUG'}
null_logger = logging.getLogger('jsonargparse_null_logger')
null_logger.addHandler(logging.NullHandler())
null_logger.parent = None


NoneType = type(None)


default_config_option_help = 'Path to a configuration file.'


[docs]class ParserError(Exception): """Error raised when parsing a value fails."""
class DebugException(Exception): pass class JsonargparseWarning(UserWarning): pass def warning(message, category=JsonargparseWarning, stacklevel=1): warnings.warn( re.sub('\n\n+', '\n\n', re.sub('\n +', '\n ', message)), category=category, stacklevel=stacklevel+1, ) class CaptureParserException(Exception): def __init__(self, parser: Optional[ArgumentParser]): self.parser = parser super().__init__('' if parser else 'No parse_args call to capture the parser.') parser_captured: ContextVar = ContextVar('parser_captured', default=False) @contextmanager def capture_parser_context(): t = parser_captured.set(True) try: yield finally: parser_captured.reset(t)
[docs]def capture_parser(function: Callable, *args, **kwargs) -> ArgumentParser: """Returns the parser object used within the execution of a function. The function execution is stopped on the start of the call to parse_args. No parsing is done or execution of instructions after the parse_args. Args: function: A callable that internally creates a parser and calls parse_args. *args: Positional arguments used to run the function. **kwargs: Keyword arguments used to run the function. Raises: CaptureParserException: If the function does not call parse_args. """ try: with capture_parser_context(): function(*args, **kwargs) except CaptureParserException as ex: return ex.parser # type: ignore raise CaptureParserException(None)
def return_parser_if_captured(parser: ArgumentParser): if parser_captured.get(): raise CaptureParserException(parser) def identity(value): return value NestedArg = namedtuple('NestedArg', 'key val') def parse_value_or_config(value: Any, enable_path: bool = True, simple_types: bool = False) -> Tuple[Any, Optional['Path']]: """Parses yaml/json config in a string or a path""" nested_arg: Union[bool, NestedArg] = False if isinstance(value, NestedArg): nested_arg = value value = nested_arg.val cfg_path = None if enable_path and type(value) is str: try: cfg_path = Path(value, mode=get_config_read_mode()) except TypeError: pass else: with change_to_path_dir(cfg_path): value = load_value(cfg_path.get_content(), simple_types=simple_types) if type(value) is str and value.strip() != '': parsed_val = load_value(value, simple_types=simple_types) if type(parsed_val) is not str: value = parsed_val if isinstance(value, dict) and cfg_path is not None: value['__path__'] = cfg_path if nested_arg: value = NestedArg(key=nested_arg.key, val=value) # type: ignore return value, cfg_path
[docs]def usage_and_exit_error_handler(parser: 'ArgumentParser', message: str) -> None: """Error handler that prints the usage and exits with error code 2 (same behavior as argparse). If the JSONARGPARSE_DEBUG environment variable is set, instead of exit, a DebugException is raised. Args: parser: The parser object. message: The message describing the error being handled. """ parser.print_usage(sys.stderr) args = {'prog': parser.prog, 'message': message} sys.stderr.write('%(prog)s: error: %(message)s\n' % args) if 'JSONARGPARSE_DEBUG' in os.environ: raise DebugException('jsonargparse debug enabled, thus raising exception instead of exit.') else: parser.exit(2)
def is_subclass(cls, class_or_tuple): """Extension of issubclass that supports non-class arguments.""" try: return inspect.isclass(cls) and issubclass(cls, class_or_tuple) except TypeError: return False def import_object(name: str): """Returns an object in a module given its dot import path.""" if not isinstance(name, str) or '.' not in name: raise ValueError(f'Expected a dot import path string: {name}') if not all(x.isidentifier() for x in name.split('.')): raise ValueError(f'Unexpected import path format: {name}') name_module, name_object = name.rsplit('.', 1) try: parent = __import__(name_module, fromlist=[name_object]) except ModuleNotFoundError as ex: if '.' not in name_module: raise ex name_module, name_object1 = name_module.rsplit('.', 1) parent = getattr(__import__(name_module, fromlist=[name_object1]), name_object1) return getattr(parent, name_object) def import_module_leaf(name: str): """Similar to __import__(name) but returns the leaf module instead of the root.""" if '.' in name: name_parent, name_leaf = name.rsplit('.', 1) parent = __import__(name_parent, fromlist=[name_leaf]) module = getattr(parent, name_leaf) else: module = __import__(name) return module unresolvable_import_paths = {}
[docs]def register_unresolvable_import_paths(*modules: ModuleType): """Saves import paths of module objects for which its import path is unresolvable from the object alone. Objects with unresolvable import paths have the __module__ attribute set to None. """ for module in modules: for val in vars(module).values(): if getattr(val, '__module__', None) is None and \ getattr(val, '__name__', None) and \ type(val) in {BuiltinFunctionType, FunctionType, Type}: unresolvable_import_paths[val] = f'{module.__name__}.{val.__name__}'
def get_import_path(value): """Returns the shortest dot import path for the given object.""" module_path = getattr(value, '__module__', None) if module_path is None: path = unresolvable_import_paths.get(value) if not path: raise ValueError(f'Not possible to determine the import path for object {value}.') module_path = path.rsplit('.', 1)[0] else: path = module_path + '.' + value.__qualname__ if '.' in module_path: module_parts = module_path.split('.') for num in range(len(module_parts)): module_path = '.'.join(module_parts[:num+1]) module = import_module_leaf(module_path) if '.' in value.__qualname__: obj_name, attr = value.__qualname__.rsplit('.', 1) obj = getattr(module, obj_name, None) if getattr(obj, attr, None) is value: path = module_path + '.' + value.__qualname__ break elif getattr(module, value.__qualname__, None) is value: path = module_path + '.' + value.__qualname__ break return path def object_path_serializer(value): try: path = get_import_path(value) reimported = import_object(path) if value is not reimported: raise ValueError return path except Exception as ex: raise ValueError(f'Only possible to serialize an importable object, given {value}: {ex}') from ex lenient_check: ContextVar = ContextVar('lenient_check', default=False) @contextmanager def lenient_check_context(caller=None, lenient=True): t = lenient_check.set(False if caller == 'argcomplete' else lenient) try: yield finally: lenient_check.reset(t) @contextmanager def change_to_path_dir(path: Optional['Path']): """A context manager for running code in the directory of a path.""" chdir = path is not None and not (path.is_url or path.is_fsspec) if chdir: cwd = os.getcwd() os.chdir(os.path.abspath(os.path.dirname(str(path)))) try: yield None finally: if chdir: os.chdir(cwd) def iter_to_set_str(val, sep=','): val = list(val) if len(val) == 1: return str(val[0]) return '{'+sep.join(str(x) for x in val)+'}' def indent_text(text: str) -> str: return text.replace('\n', '\n ') def get_private_kwargs(kwargs, items): extracted = [kwargs.pop(name, default) for name, default in items.items()] if kwargs: raise ValueError(f'Unexpected keyword parameters: {set(kwargs.keys())}') return extracted[0] if len(extracted) == 1 else extracted def known_to_fsspec(path: str) -> bool: import_fsspec('known_to_fsspec') from fsspec.registry import known_implementations for protocol in known_implementations.keys(): if path.startswith(protocol+'://') or path.startswith(protocol+'::'): return True return False class ClassFromFunctionBase: wrapped_function: Callable ClassType = TypeVar('ClassType')
[docs]def class_from_function(func: Callable[..., ClassType]) -> Type[ClassType]: """Creates a dynamic class which if instantiated is equivalent to calling func. Args: func: A function that returns an instance of a class. It must have a return type annotation. """ func_return = inspect.signature(func).return_annotation if isinstance(func_return, str): caller_frame = inspect.currentframe().f_back # type: ignore func_return = caller_frame.f_locals.get(func_return) or caller_frame.f_globals.get(func_return) # type: ignore if func_return is None: raise ValueError(f'Unable to dereference {func_return} the return type of {func}.') @wraps(func) def __new__(cls, *args, **kwargs): return func(*args, **kwargs) class ClassFromFunction(func_return, ClassFromFunctionBase): # type: ignore pass ClassFromFunction.wrapped_function = func ClassFromFunction.__new__ = __new__ # type: ignore ClassFromFunction.__doc__ = func.__doc__ ClassFromFunction.__name__ = func.__name__ return ClassFromFunction
[docs]class Path: """Stores a (possibly relative) path and the corresponding absolute path. When a Path instance is created it is checked that: the path exists, whether it is a file or directory and whether has the required access permissions (f=file, d=directory, r=readable, w=writeable, x=executable, c=creatable, u=url, s=fsspec or in uppercase meaning not, i.e., F=not-file, D=not-directory, R=not-readable, W=not-writeable and X=not-executable). The absolute path can be obtained without having to remember the working directory from when the object was created. """ file_scheme = re.compile('^file:///?')
[docs] def __init__( self, path: Union[str, 'Path'], mode: str = 'fr', cwd: Optional[str] = None, skip_check: bool = False, ): """Initializer for Path instance. Args: path: The path to check and store. mode: The required type and access permissions among [fdrwxcuFDRWX]. cwd: Working directory for relative paths. If None, then os.getcwd() is used. skip_check: Whether to skip path checks. Raises: ValueError: If the provided mode is invalid. TypeError: If the path does not exist or does not agree with the mode. """ self._check_mode(mode) if cwd is None: cwd = os.getcwd() is_url = False is_fsspec = False if isinstance(path, Path): is_url = path.is_url is_fsspec = path.is_fsspec cwd = path.cwd # type: ignore abs_path = path.abs_path # type: ignore path = path.rel_path # type: ignore elif isinstance(path, str): abs_path = os.path.expanduser(path) if self.file_scheme.match(abs_path): abs_path = self.file_scheme.sub('' if os.name == 'nt' else '/', abs_path) if 'u' in mode and url_support and import_url_validator('Path')(abs_path): is_url = True elif 's' in mode and fsspec_support and known_to_fsspec(abs_path): is_fsspec = True elif 'f' in mode or 'd' in mode: abs_path = abs_path if os.path.isabs(abs_path) else os.path.join(cwd, abs_path) else: raise TypeError('Expected path to be a string or a Path object.') if not skip_check and is_url: if 'r' in mode: requests = import_requests('Path with URL support') try: requests.head(abs_path).raise_for_status() except requests.HTTPError as ex: raise TypeError(f'{abs_path} HEAD not accessible :: {ex}') from ex elif not skip_check and is_fsspec: fsspec_mode = ''.join(c for c in mode if c in {'r','w'}) if fsspec_mode: fsspec = import_fsspec('Path') try: handle = fsspec.open(abs_path, fsspec_mode) handle.open() handle.close() except (FileNotFoundError, KeyError): raise TypeError('Path does not exist: '+abs_path) except PermissionError: raise TypeError('Path exists but no permission to access: '+abs_path) elif not skip_check: ptype = 'Directory' if 'd' in mode else 'File' if 'c' in mode: pdir = os.path.realpath(os.path.join(abs_path, '..')) if not os.path.isdir(pdir): raise TypeError(ptype+' is not creatable since parent directory does not exist: '+abs_path) if not os.access(pdir, os.W_OK): raise TypeError(ptype+' is not creatable since parent directory not writeable: '+abs_path) if 'd' in mode and os.access(abs_path, os.F_OK) and not os.path.isdir(abs_path): raise TypeError(ptype+' is not creatable since path already exists: '+abs_path) if 'f' in mode and os.access(abs_path, os.F_OK) and not os.path.isfile(abs_path): raise TypeError(ptype+' is not creatable since path already exists: '+abs_path) else: if not os.access(abs_path, os.F_OK): raise TypeError(ptype+' does not exist: '+abs_path) if 'd' in mode and not os.path.isdir(abs_path): raise TypeError('Path is not a directory: '+abs_path) if 'f' in mode and not (os.path.isfile(abs_path) or stat.S_ISFIFO(os.stat(abs_path).st_mode)): raise TypeError('Path is not a file: '+abs_path) if 'r' in mode and not os.access(abs_path, os.R_OK): raise TypeError(ptype+' is not readable: '+abs_path) if 'w' in mode and not os.access(abs_path, os.W_OK): raise TypeError(ptype+' is not writeable: '+abs_path) if 'x' in mode and not os.access(abs_path, os.X_OK): raise TypeError(ptype+' is not executable: '+abs_path) if 'D' in mode and os.path.isdir(abs_path): raise TypeError('Path is a directory: '+abs_path) if 'F' in mode and (os.path.isfile(abs_path) or stat.S_ISFIFO(os.stat(abs_path).st_mode)): raise TypeError('Path is a file: '+abs_path) if 'R' in mode and os.access(abs_path, os.R_OK): raise TypeError(ptype+' is readable: '+abs_path) if 'W' in mode and os.access(abs_path, os.W_OK): raise TypeError(ptype+' is writeable: '+abs_path) if 'X' in mode and os.access(abs_path, os.X_OK): raise TypeError(ptype+' is executable: '+abs_path) self.rel_path = path self.abs_path = abs_path self.cwd = cwd self.mode = mode self.is_url: bool = is_url self.is_fsspec: bool = is_fsspec self.skip_check = skip_check
def __str__(self): return self.rel_path def __repr__(self): cwd = '' if self.rel_path == self.abs_path else ', cwd='+self.cwd name = 'Path_'+self.mode if self.skip_check: name += '_skip_check' return name+'('+self.rel_path+cwd+')'
[docs] def __call__(self, absolute:bool=True) -> str: """Returns the path as a string. Args: absolute: If false returns the original path given, otherwise the corresponding absolute path. """ return self.abs_path if absolute else self.rel_path
[docs] def get_content(self, mode:str='r') -> str: """Returns the contents of the file or the response of a GET request to the URL.""" if self.is_url: requests = import_requests('Path with URL support') response = requests.get(self.abs_path) response.raise_for_status() return response.text elif self.is_fsspec: fsspec = import_fsspec('Path') with fsspec.open(self.abs_path, mode) as handle: with handle as input_file: return input_file.read() else: with open(self.abs_path, mode) as input_file: return input_file.read()
@staticmethod def _check_mode(mode:str): if not isinstance(mode, str): raise ValueError('Expected mode to be a string.') if len(set(mode)-set('fdrwxcusFDRWX')) > 0: raise ValueError('Expected mode to only include [fdrwxcusFDRWX] flags.') if 'f' in mode and 'd' in mode: raise ValueError('Both modes "f" and "d" not possible.') if 'u' in mode and 'd' in mode: raise ValueError('Both modes "d" and "u" not possible.') if 's' in mode and 'd' in mode: raise ValueError('Both modes "d" and "s" not possible.')
def setup_default_logger(data, level, caller): name = caller if isinstance(data, str): name = data elif isinstance(data, dict) and 'name' in data: name = data['name'] logger = logging.getLogger(name) logger.parent = None if len(logger.handlers) == 0: handler = logging.StreamHandler() handler.setFormatter(logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')) logger.addHandler(handler) level = getattr(logging, level) for handler in logger.handlers: handler.setLevel(level) return logger def parse_logger(logger: Union[bool, str, dict, logging.Logger], caller): if not isinstance(logger, (bool, str, dict, logging.Logger)): raise ValueError(f'Expected logger to be an instance of (bool, str, dict, logging.Logger), but got {logger}.') if isinstance(logger, dict) and len(set(logger.keys())-{'name', 'level'}) > 0: value = {k: v for k, v in logger.items() if k not in {'name', 'level'}} raise ValueError(f'Unexpected data to configure logger: {value}.') if logger is False: return null_logger level = 'WARNING' if isinstance(logger, dict) and 'level' in logger: level = logger['level'] if level not in logging_levels: raise ValueError(f'Got logger level {level!r} but must be one of {logging_levels}.') if (logger is True or (isinstance(logger, dict) and 'name' not in logger)) and reconplogger_support: logger = import_reconplogger('parse_logger').logger_setup(level=level) if not isinstance(logger, logging.Logger): logger = setup_default_logger(logger, level, caller) return logger
[docs]class LoggerProperty: """Class designed to be inherited by other classes to add a logger property."""
[docs] def __init__(self, *args, logger: Union[bool, str, dict, logging.Logger] = False, **kwargs): """Initializer for LoggerProperty class.""" self.logger = logger super().__init__(*args, **kwargs)
@property def logger(self): """The logger property for the class. :getter: Returns the current logger. :setter: Sets the given logging.Logger as logger or sets the default logger if given True/str(logger name)/dict(name, level), or disables logging if given False. Raises: ValueError: If an invalid logger value is given. """ return self._logger @logger.setter def logger(self, logger: Union[bool, str, dict, logging.Logger]): if logger is None: from .deprecated import deprecation_warning, logger_property_none_message deprecation_warning((LoggerProperty.logger, None), logger_property_none_message) logger = False if not logger and 'JSONARGPARSE_DEBUG' in os.environ: logger = {'level': 'DEBUG'} self._logger = parse_logger(logger, type(self).__name__)
if 'JSONARGPARSE_DEBUG' in os.environ: os.environ['LOGGER_LEVEL'] = 'DEBUG' # pragma: no cover