Edit File: creator.py
import json import logging import os import sys from abc import ABCMeta, abstractmethod from argparse import ArgumentTypeError from ast import literal_eval from collections import OrderedDict from pathlib import Path from virtualenv.discovery.cached_py_info import LogCmd from virtualenv.util.path import safe_delete from virtualenv.util.subprocess import run_cmd from virtualenv.version import __version__ from .pyenv_cfg import PyEnvCfg HERE = Path(os.path.abspath(__file__)).parent DEBUG_SCRIPT = HERE / "debug.py" class CreatorMeta: def __init__(self): self.error = None class Creator(metaclass=ABCMeta): """A class that given a python Interpreter creates a virtual environment""" def __init__(self, options, interpreter): """Construct a new virtual environment creator. :param options: the CLI option as parsed from :meth:`add_parser_arguments` :param interpreter: the interpreter to create virtual environment from """ self.interpreter = interpreter self._debug = None self.dest = Path(options.dest) self.clear = options.clear self.no_vcs_ignore = options.no_vcs_ignore self.pyenv_cfg = PyEnvCfg.from_folder(self.dest) self.app_data = options.app_data self.env = options.env def __repr__(self): return f"{self.__class__.__name__}({', '.join(f'{k}={v}' for k, v in self._args())})" def _args(self): return [ ("dest", str(self.dest)), ("clear", self.clear), ("no_vcs_ignore", self.no_vcs_ignore), ] @classmethod def can_create(cls, interpreter): # noqa: U100 """Determine if we can create a virtual environment. :param interpreter: the interpreter in question :return: ``None`` if we can't create, any other object otherwise that will be forwarded to \ :meth:`add_parser_arguments` """ return True @classmethod def add_parser_arguments(cls, parser, interpreter, meta, app_data): # noqa: U100 """Add CLI arguments for the creator. :param parser: the CLI parser :param app_data: the application data folder :param interpreter: the interpreter we're asked to create virtual environment for :param meta: value as returned by :meth:`can_create` """ parser.add_argument( "dest", help="directory to create virtualenv at", type=cls.validate_dest, ) parser.add_argument( "--clear", dest="clear", action="store_true", help="remove the destination directory if exist before starting (will overwrite files otherwise)", default=False, ) parser.add_argument( "--no-vcs-ignore", dest="no_vcs_ignore", action="store_true", help="don't create VCS ignore directive in the destination directory", default=False, ) @abstractmethod def create(self): """Perform the virtual environment creation.""" raise NotImplementedError @classmethod def validate_dest(cls, raw_value): """No path separator in the path, valid chars and must be write-able""" def non_write_able(dest, value): common = Path(*os.path.commonprefix([value.parts, dest.parts])) raise ArgumentTypeError(f"the destination {dest.relative_to(common)} is not write-able at {common}") # the file system must be able to encode # note in newer CPython this is always utf-8 https://www.python.org/dev/peps/pep-0529/ encoding = sys.getfilesystemencoding() refused = OrderedDict() kwargs = {"errors": "ignore"} if encoding != "mbcs" else {} for char in str(raw_value): try: trip = char.encode(encoding, **kwargs).decode(encoding) if trip == char: continue raise ValueError(trip) except ValueError: refused[char] = None if refused: bad = "".join(refused.keys()) msg = f"the file system codec ({encoding}) cannot handle characters {bad!r} within {raw_value!r}" raise ArgumentTypeError(msg) if os.pathsep in raw_value: msg = f"destination {raw_value!r} must not contain the path separator ({os.pathsep})" raise ArgumentTypeError(f"{msg} as this would break the activation scripts") value = Path(raw_value) if value.exists() and value.is_file(): raise ArgumentTypeError(f"the destination {value} already exists and is a file") dest = Path(os.path.abspath(str(value))).resolve() # on Windows absolute does not imply resolve so use both value = dest while dest: if dest.exists(): if os.access(str(dest), os.W_OK): break else: non_write_able(dest, value) base, _ = dest.parent, dest.name if base == dest: non_write_able(dest, value) # pragma: no cover dest = base return str(value) def run(self): if self.dest.exists() and self.clear: logging.debug("delete %s", self.dest) safe_delete(self.dest) self.create() self.set_pyenv_cfg() if not self.no_vcs_ignore: self.setup_ignore_vcs() def set_pyenv_cfg(self): self.pyenv_cfg.content = OrderedDict() self.pyenv_cfg["home"] = os.path.dirname(os.path.abspath(self.interpreter.system_executable)) self.pyenv_cfg["implementation"] = self.interpreter.implementation self.pyenv_cfg["version_info"] = ".".join(str(i) for i in self.interpreter.version_info) self.pyenv_cfg["virtualenv"] = __version__ def setup_ignore_vcs(self): """Generate ignore instructions for version control systems.""" # mark this folder to be ignored by VCS, handle https://www.python.org/dev/peps/pep-0610/#registered-vcs git_ignore = self.dest / ".gitignore" if not git_ignore.exists(): git_ignore.write_text("# created by virtualenv automatically\n*\n") # Mercurial - does not support the .hgignore file inside a subdirectory directly, but only if included via the # subinclude directive from root, at which point on might as well ignore the directory itself, see # https://www.selenic.com/mercurial/hgignore.5.html for more details # Bazaar - does not support ignore files in sub-directories, only at root level via .bzrignore # Subversion - does not support ignore files, requires direct manipulation with the svn tool @property def debug(self): """ :return: debug information about the virtual environment (only valid after :meth:`create` has run) """ if self._debug is None and self.exe is not None: self._debug = get_env_debug_info(self.exe, self.debug_script(), self.app_data, self.env) return self._debug @staticmethod def debug_script(): return DEBUG_SCRIPT def get_env_debug_info(env_exe, debug_script, app_data, env): env = env.copy() env.pop("PYTHONPATH", None) with app_data.ensure_extracted(debug_script) as debug_script: cmd = [str(env_exe), str(debug_script)] logging.debug("debug via %r", LogCmd(cmd)) code, out, err = run_cmd(cmd) try: if code != 0: if out: result = literal_eval(out) else: if code == 2 and "file" in err: # Re-raise FileNotFoundError from `run_cmd()` raise OSError(err) raise Exception(err) else: result = json.loads(out) if err: result["err"] = err except Exception as exception: return {"out": out, "err": err, "returncode": code, "exception": repr(exception)} if "sys" in result and "path" in result["sys"]: del result["sys"]["path"][0] return result __all__ = [ "Creator", "CreatorMeta", ]