JezK
Edit File: temp_dir.py
import errno import itertools import logging import os.path import tempfile from contextlib import ExitStack, contextmanager from typing import Any, Dict, Generator, Optional, TypeVar, Union from pip._internal.utils.misc import enum, rmtree logger = logging.getLogger(__name__) _T = TypeVar("_T", bound="TempDirectory") # Kinds of temporary directories. Only needed for ones that are # globally-managed. tempdir_kinds = enum( BUILD_ENV="build-env", EPHEM_WHEEL_CACHE="ephem-wheel-cache", REQ_BUILD="req-build", ) _tempdir_manager: Optional[ExitStack] = None @contextmanager def global_tempdir_manager() -> Generator[None, None, None]: global _tempdir_manager with ExitStack() as stack: old_tempdir_manager, _tempdir_manager = _tempdir_manager, stack try: yield finally: _tempdir_manager = old_tempdir_manager class TempDirectoryTypeRegistry: """Manages temp directory behavior""" def __init__(self) -> None: self._should_delete: Dict[str, bool] = {} def set_delete(self, kind: str, value: bool) -> None: """Indicate whether a TempDirectory of the given kind should be auto-deleted. """ self._should_delete[kind] = value def get_delete(self, kind: str) -> bool: """Get configured auto-delete flag for a given TempDirectory type, default True. """ return self._should_delete.get(kind, True) _tempdir_registry: Optional[TempDirectoryTypeRegistry] = None @contextmanager def tempdir_registry() -> Generator[TempDirectoryTypeRegistry, None, None]: """Provides a scoped global tempdir registry that can be used to dictate whether directories should be deleted. """ global _tempdir_registry old_tempdir_registry = _tempdir_registry _tempdir_registry = TempDirectoryTypeRegistry() try: yield _tempdir_registry finally: _tempdir_registry = old_tempdir_registry class _Default: pass _default = _Default() class TempDirectory: """Helper class that owns and cleans up a temporary directory. This class can be used as a context manager or as an OO representation of a temporary directory. Attributes: path Location to the created temporary directory delete Whether the directory should be deleted when exiting (when used as a contextmanager) Methods: cleanup() Deletes the temporary directory When used as a context manager, if the delete attribute is True, on exiting the context the temporary directory is deleted. """ def __init__( self, path: Optional[str] = None, delete: Union[bool, None, _Default] = _default, kind: str = "temp", globally_managed: bool = False, ): super().__init__() if delete is _default: if path is not None: # If we were given an explicit directory, resolve delete option # now. delete = False else: # Otherwise, we wait until cleanup and see what # tempdir_registry says. delete = None # The only time we specify path is in for editables where it # is the value of the --src option. if path is None: path = self._create(kind) self._path = path self._deleted = False self.delete = delete self.kind = kind if globally_managed: assert _tempdir_manager is not None _tempdir_manager.enter_context(self) @property def path(self) -> str: assert not self._deleted, f"Attempted to access deleted path: {self._path}" return self._path def __repr__(self) -> str: return f"<{self.__class__.__name__} {self.path!r}>" def __enter__(self: _T) -> _T: return self def __exit__(self, exc: Any, value: Any, tb: Any) -> None: if self.delete is not None: delete = self.delete elif _tempdir_registry: delete = _tempdir_registry.get_delete(self.kind) else: delete = True if delete: self.cleanup() def _create(self, kind: str) -> str: """Create a temporary directory and store its path in self.path""" # We realpath here because some systems have their default tmpdir # symlinked to another directory. This tends to confuse build # scripts, so we canonicalize the path by traversing potential # symlinks here. path = os.path.realpath(tempfile.mkdtemp(prefix=f"pip-{kind}-")) logger.debug("Created temporary directory: %s", path) return path def cleanup(self) -> None: """Remove the temporary directory created and reset state""" self._deleted = True if not os.path.exists(self._path): return rmtree(self._path) class AdjacentTempDirectory(TempDirectory): """Helper class that creates a temporary directory adjacent to a real one. Attributes: original The original directory to create a temp directory for. path After calling create() or entering, contains the full path to the temporary directory. delete Whether the directory should be deleted when exiting (when used as a contextmanager) """ # The characters that may be used to name the temp directory # We always prepend a ~ and then rotate through these until # a usable name is found. # pkg_resources raises a different error for .dist-info folder # with leading '-' and invalid metadata LEADING_CHARS = "-~.=%0123456789" def __init__(self, original: str, delete: Optional[bool] = None) -> None: self.original = original.rstrip("/\\") super().__init__(delete=delete) @classmethod def _generate_names(cls, name: str) -> Generator[str, None, None]: """Generates a series of temporary names. The algorithm replaces the leading characters in the name with ones that are valid filesystem characters, but are not valid package names (for both Python and pip definitions of package). """ for i in range(1, len(name)): for candidate in itertools.combinations_with_replacement( cls.LEADING_CHARS, i - 1 ): new_name = "~" + "".join(candidate) + name[i:] if new_name != name: yield new_name # If we make it this far, we will have to make a longer name for i in range(len(cls.LEADING_CHARS)): for candidate in itertools.combinations_with_replacement( cls.LEADING_CHARS, i ): new_name = "~" + "".join(candidate) + name if new_name != name: yield new_name def _create(self, kind: str) -> str: root, name = os.path.split(self.original) for candidate in self._generate_names(name): path = os.path.join(root, candidate) try: os.mkdir(path) except OSError as ex: # Continue if the name exists already if ex.errno != errno.EEXIST: raise else: path = os.path.realpath(path) break else: # Final fallback on the default behavior. path = os.path.realpath(tempfile.mkdtemp(prefix=f"pip-{kind}-")) logger.debug("Created temporary directory: %s", path) return path