JezK
Edit File: expand.py
"""Utility functions to expand configuration directives or special values (such glob patterns). We can split the process of interpreting configuration files into 2 steps: 1. The parsing the file contents from strings to value objects that can be understand by Python (for example a string with a comma separated list of keywords into an actual Python list of strings). 2. The expansion (or post-processing) of these values according to the semantics ``setuptools`` assign to them (for example a configuration field with the ``file:`` directive should be expanded from a list of file paths to a single string with the contents of those files concatenated) This module focus on the second step, and therefore allow sharing the expansion functions among several configuration file formats. **PRIVATE MODULE**: API reserved for setuptools internal usage only. """ import ast import importlib import io import os import pathlib import sys import warnings from glob import iglob from configparser import ConfigParser from importlib.machinery import ModuleSpec from itertools import chain from typing import ( TYPE_CHECKING, Callable, Dict, Iterable, Iterator, List, Mapping, Optional, Tuple, TypeVar, Union, cast ) from pathlib import Path from types import ModuleType from distutils.errors import DistutilsOptionError from .._path import same_path as _same_path if TYPE_CHECKING: from setuptools.dist import Distribution # noqa from setuptools.discovery import ConfigDiscovery # noqa from distutils.dist import DistributionMetadata # noqa chain_iter = chain.from_iterable _Path = Union[str, os.PathLike] _K = TypeVar("_K") _V = TypeVar("_V", covariant=True) class StaticModule: """Proxy to a module object that avoids executing arbitrary code.""" def __init__(self, name: str, spec: ModuleSpec): module = ast.parse(pathlib.Path(spec.origin).read_bytes()) vars(self).update(locals()) del self.self def _find_assignments(self) -> Iterator[Tuple[ast.AST, ast.AST]]: for statement in self.module.body: if isinstance(statement, ast.Assign): yield from ((target, statement.value) for target in statement.targets) elif isinstance(statement, ast.AnnAssign) and statement.value: yield (statement.target, statement.value) def __getattr__(self, attr): """Attempt to load an attribute "statically", via :func:`ast.literal_eval`.""" try: return next( ast.literal_eval(value) for target, value in self._find_assignments() if isinstance(target, ast.Name) and target.id == attr ) except Exception as e: raise AttributeError(f"{self.name} has no attribute {attr}") from e def glob_relative( patterns: Iterable[str], root_dir: Optional[_Path] = None ) -> List[str]: """Expand the list of glob patterns, but preserving relative paths. :param list[str] patterns: List of glob patterns :param str root_dir: Path to which globs should be relative (current directory by default) :rtype: list """ glob_characters = {'*', '?', '[', ']', '{', '}'} expanded_values = [] root_dir = root_dir or os.getcwd() for value in patterns: # Has globby characters? if any(char in value for char in glob_characters): # then expand the glob pattern while keeping paths *relative*: glob_path = os.path.abspath(os.path.join(root_dir, value)) expanded_values.extend(sorted( os.path.relpath(path, root_dir).replace(os.sep, "/") for path in iglob(glob_path, recursive=True))) else: # take the value as-is path = os.path.relpath(value, root_dir).replace(os.sep, "/") expanded_values.append(path) return expanded_values def read_files(filepaths: Union[str, bytes, Iterable[_Path]], root_dir=None) -> str: """Return the content of the files concatenated using ``\n`` as str This function is sandboxed and won't reach anything outside ``root_dir`` (By default ``root_dir`` is the current directory). """ from setuptools.extern.more_itertools import always_iterable root_dir = os.path.abspath(root_dir or os.getcwd()) _filepaths = (os.path.join(root_dir, path) for path in always_iterable(filepaths)) return '\n'.join( _read_file(path) for path in _filter_existing_files(_filepaths) if _assert_local(path, root_dir) ) def _filter_existing_files(filepaths: Iterable[_Path]) -> Iterator[_Path]: for path in filepaths: if os.path.isfile(path): yield path else: warnings.warn(f"File {path!r} cannot be found") def _read_file(filepath: Union[bytes, _Path]) -> str: with io.open(filepath, encoding='utf-8') as f: return f.read() def _assert_local(filepath: _Path, root_dir: str): if Path(os.path.abspath(root_dir)) not in Path(os.path.abspath(filepath)).parents: msg = f"Cannot access {filepath!r} (or anything outside {root_dir!r})" raise DistutilsOptionError(msg) return True def read_attr( attr_desc: str, package_dir: Optional[Mapping[str, str]] = None, root_dir: Optional[_Path] = None ): """Reads the value of an attribute from a module. This function will try to read the attributed statically first (via :func:`ast.literal_eval`), and only evaluate the module if it fails. Examples: read_attr("package.attr") read_attr("package.module.attr") :param str attr_desc: Dot-separated string describing how to reach the attribute (see examples above) :param dict[str, str] package_dir: Mapping of package names to their location in disk (represented by paths relative to ``root_dir``). :param str root_dir: Path to directory containing all the packages in ``package_dir`` (current directory by default). :rtype: str """ root_dir = root_dir or os.getcwd() attrs_path = attr_desc.strip().split('.') attr_name = attrs_path.pop() module_name = '.'.join(attrs_path) module_name = module_name or '__init__' _parent_path, path, module_name = _find_module(module_name, package_dir, root_dir) spec = _find_spec(module_name, path) try: return getattr(StaticModule(module_name, spec), attr_name) except Exception: # fallback to evaluate module module = _load_spec(spec, module_name) return getattr(module, attr_name) def _find_spec(module_name: str, module_path: Optional[_Path]) -> ModuleSpec: spec = importlib.util.spec_from_file_location(module_name, module_path) spec = spec or importlib.util.find_spec(module_name) if spec is None: raise ModuleNotFoundError(module_name) return spec def _load_spec(spec: ModuleSpec, module_name: str) -> ModuleType: name = getattr(spec, "__name__", module_name) if name in sys.modules: return sys.modules[name] module = importlib.util.module_from_spec(spec) sys.modules[name] = module # cache (it also ensures `==` works on loaded items) spec.loader.exec_module(module) # type: ignore return module def _find_module( module_name: str, package_dir: Optional[Mapping[str, str]], root_dir: _Path ) -> Tuple[_Path, Optional[str], str]: """Given a module (that could normally be imported by ``module_name`` after the build is complete), find the path to the parent directory where it is contained and the canonical name that could be used to import it considering the ``package_dir`` in the build configuration and ``root_dir`` """ parent_path = root_dir module_parts = module_name.split('.') if package_dir: if module_parts[0] in package_dir: # A custom path was specified for the module we want to import custom_path = package_dir[module_parts[0]] parts = custom_path.rsplit('/', 1) if len(parts) > 1: parent_path = os.path.join(root_dir, parts[0]) parent_module = parts[1] else: parent_module = custom_path module_name = ".".join([parent_module, *module_parts[1:]]) elif '' in package_dir: # A custom parent directory was specified for all root modules parent_path = os.path.join(root_dir, package_dir['']) path_start = os.path.join(parent_path, *module_name.split(".")) candidates = chain( (f"{path_start}.py", os.path.join(path_start, "__init__.py")), iglob(f"{path_start}.*") ) module_path = next((x for x in candidates if os.path.isfile(x)), None) return parent_path, module_path, module_name def resolve_class( qualified_class_name: str, package_dir: Optional[Mapping[str, str]] = None, root_dir: Optional[_Path] = None ) -> Callable: """Given a qualified class name, return the associated class object""" root_dir = root_dir or os.getcwd() idx = qualified_class_name.rfind('.') class_name = qualified_class_name[idx + 1 :] pkg_name = qualified_class_name[:idx] _parent_path, path, module_name = _find_module(pkg_name, package_dir, root_dir) module = _load_spec(_find_spec(module_name, path), module_name) return getattr(module, class_name) def cmdclass( values: Dict[str, str], package_dir: Optional[Mapping[str, str]] = None, root_dir: Optional[_Path] = None ) -> Dict[str, Callable]: """Given a dictionary mapping command names to strings for qualified class names, apply :func:`resolve_class` to the dict values. """ return {k: resolve_class(v, package_dir, root_dir) for k, v in values.items()} def find_packages( *, namespaces=True, fill_package_dir: Optional[Dict[str, str]] = None, root_dir: Optional[_Path] = None, **kwargs ) -> List[str]: """Works similarly to :func:`setuptools.find_packages`, but with all arguments given as keyword arguments. Moreover, ``where`` can be given as a list (the results will be simply concatenated). When the additional keyword argument ``namespaces`` is ``True``, it will behave like :func:`setuptools.find_namespace_packages`` (i.e. include implicit namespaces as per :pep:`420`). The ``where`` argument will be considered relative to ``root_dir`` (or the current working directory when ``root_dir`` is not given). If the ``fill_package_dir`` argument is passed, this function will consider it as a similar data structure to the ``package_dir`` configuration parameter add fill-in any missing package location. :rtype: list """ from setuptools.discovery import construct_package_dir from setuptools.extern.more_itertools import unique_everseen, always_iterable if namespaces: from setuptools.discovery import PEP420PackageFinder as PackageFinder else: from setuptools.discovery import PackageFinder # type: ignore root_dir = root_dir or os.curdir where = kwargs.pop('where', ['.']) packages: List[str] = [] fill_package_dir = {} if fill_package_dir is None else fill_package_dir search = list(unique_everseen(always_iterable(where))) if len(search) == 1 and all(not _same_path(search[0], x) for x in (".", root_dir)): fill_package_dir.setdefault("", search[0]) for path in search: package_path = _nest_path(root_dir, path) pkgs = PackageFinder.find(package_path, **kwargs) packages.extend(pkgs) if pkgs and not ( fill_package_dir.get("") == path or os.path.samefile(package_path, root_dir) ): fill_package_dir.update(construct_package_dir(pkgs, path)) return packages def _nest_path(parent: _Path, path: _Path) -> str: path = parent if path in {".", ""} else os.path.join(parent, path) return os.path.normpath(path) def version(value: Union[Callable, Iterable[Union[str, int]], str]) -> str: """When getting the version directly from an attribute, it should be normalised to string. """ if callable(value): value = value() value = cast(Iterable[Union[str, int]], value) if not isinstance(value, str): if hasattr(value, '__iter__'): value = '.'.join(map(str, value)) else: value = '%s' % value return value def canonic_package_data(package_data: dict) -> dict: if "*" in package_data: package_data[""] = package_data.pop("*") return package_data def canonic_data_files( data_files: Union[list, dict], root_dir: Optional[_Path] = None ) -> List[Tuple[str, List[str]]]: """For compatibility with ``setup.py``, ``data_files`` should be a list of pairs instead of a dict. This function also expands glob patterns. """ if isinstance(data_files, list): return data_files return [ (dest, glob_relative(patterns, root_dir)) for dest, patterns in data_files.items() ] def entry_points(text: str, text_source="entry-points") -> Dict[str, dict]: """Given the contents of entry-points file, process it into a 2-level dictionary (``dict[str, dict[str, str]]``). The first level keys are entry-point groups, the second level keys are entry-point names, and the second level values are references to objects (that correspond to the entry-point value). """ parser = ConfigParser(default_section=None, delimiters=("=",)) # type: ignore parser.optionxform = str # case sensitive parser.read_string(text, text_source) groups = {k: dict(v.items()) for k, v in parser.items()} groups.pop(parser.default_section, None) return groups class EnsurePackagesDiscovered: """Some expand functions require all the packages to already be discovered before they run, e.g. :func:`read_attr`, :func:`resolve_class`, :func:`cmdclass`. Therefore in some cases we will need to run autodiscovery during the evaluation of the configuration. However, it is better to postpone calling package discovery as much as possible, because some parameters can influence it (e.g. ``package_dir``), and those might not have been processed yet. """ def __init__(self, distribution: "Distribution"): self._dist = distribution self._called = False def __call__(self): """Trigger the automatic package discovery, if it is still necessary.""" if not self._called: self._called = True self._dist.set_defaults(name=False) # Skip name, we can still be parsing def __enter__(self): return self def __exit__(self, _exc_type, _exc_value, _traceback): if self._called: self._dist.set_defaults.analyse_name() # Now we can set a default name def _get_package_dir(self) -> Mapping[str, str]: self() pkg_dir = self._dist.package_dir return {} if pkg_dir is None else pkg_dir @property def package_dir(self) -> Mapping[str, str]: """Proxy to ``package_dir`` that may trigger auto-discovery when used.""" return LazyMappingProxy(self._get_package_dir) class LazyMappingProxy(Mapping[_K, _V]): """Mapping proxy that delays resolving the target object, until really needed. >>> def obtain_mapping(): ... print("Running expensive function!") ... return {"key": "value", "other key": "other value"} >>> mapping = LazyMappingProxy(obtain_mapping) >>> mapping["key"] Running expensive function! 'value' >>> mapping["other key"] 'other value' """ def __init__(self, obtain_mapping_value: Callable[[], Mapping[_K, _V]]): self._obtain = obtain_mapping_value self._value: Optional[Mapping[_K, _V]] = None def _target(self) -> Mapping[_K, _V]: if self._value is None: self._value = self._obtain() return self._value def __getitem__(self, key: _K) -> _V: return self._target()[key] def __len__(self) -> int: return len(self._target()) def __iter__(self) -> Iterator[_K]: return iter(self._target())