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Editing: py_info.py
""" The PythonInfo contains information about a concrete instance of a Python interpreter Note: this file is also used to query target interpreters, so can only use standard library methods """ from __future__ import absolute_import, print_function import json import logging import os import platform import re import sys import sysconfig import warnings from collections import OrderedDict, namedtuple from string import digits VersionInfo = namedtuple("VersionInfo", ["major", "minor", "micro", "releaselevel", "serial"]) def _get_path_extensions(): return list(OrderedDict.fromkeys([""] + os.environ.get("PATHEXT", "").lower().split(os.pathsep))) EXTENSIONS = _get_path_extensions() _CONF_VAR_RE = re.compile(r"\{\w+\}") class PythonInfo(object): """Contains information for a Python interpreter""" def __init__(self): def u(v): return v.decode("utf-8") if isinstance(v, bytes) else v def abs_path(v): return None if v is None else os.path.abspath(v) # unroll relative elements from path (e.g. ..) # qualifies the python self.platform = u(sys.platform) self.implementation = u(platform.python_implementation()) if self.implementation == "PyPy": self.pypy_version_info = tuple(u(i) for i in sys.pypy_version_info) # this is a tuple in earlier, struct later, unify to our own named tuple self.version_info = VersionInfo(*list(u(i) for i in sys.version_info)) self.architecture = 64 if sys.maxsize > 2 ** 32 else 32 self.version = u(sys.version) self.os = u(os.name) # information about the prefix - determines python home self.prefix = u(abs_path(getattr(sys, "prefix", None))) # prefix we think self.base_prefix = u(abs_path(getattr(sys, "base_prefix", None))) # venv self.real_prefix = u(abs_path(getattr(sys, "real_prefix", None))) # old virtualenv # information about the exec prefix - dynamic stdlib modules self.base_exec_prefix = u(abs_path(getattr(sys, "base_exec_prefix", None))) self.exec_prefix = u(abs_path(getattr(sys, "exec_prefix", None))) self.executable = u(abs_path(sys.executable)) # the executable we were invoked via self.original_executable = u(abs_path(self.executable)) # the executable as known by the interpreter self.system_executable = self._fast_get_system_executable() # the executable we are based of (if available) try: __import__("venv") has = True except ImportError: has = False self.has_venv = has self.path = [u(i) for i in sys.path] self.file_system_encoding = u(sys.getfilesystemencoding()) self.stdout_encoding = u(getattr(sys.stdout, "encoding", None)) if "venv" in sysconfig.get_scheme_names(): self.sysconfig_scheme = "venv" self.sysconfig_paths = { u(i): u(sysconfig.get_path(i, expand=False, scheme="venv")) for i in sysconfig.get_path_names() } # we cannot use distutils at all if "venv" exists, distutils don't know it self.distutils_install = {} else: self.sysconfig_scheme = None self.sysconfig_paths = {u(i): u(sysconfig.get_path(i, expand=False)) for i in sysconfig.get_path_names()} self.distutils_install = {u(k): u(v) for k, v in self._distutils_install().items()} # https://bugs.python.org/issue22199 makefile = getattr(sysconfig, "get_makefile_filename", getattr(sysconfig, "_get_makefile_filename", None)) self.sysconfig = { u(k): u(v) for k, v in [ # a list of content to store from sysconfig ("makefile_filename", makefile()), ] if k is not None } config_var_keys = set() for element in self.sysconfig_paths.values(): for k in _CONF_VAR_RE.findall(element): config_var_keys.add(u(k[1:-1])) config_var_keys.add("PYTHONFRAMEWORK") self.sysconfig_vars = {u(i): u(sysconfig.get_config_var(i) or "") for i in config_var_keys} if self.implementation == "PyPy" and sys.version_info.major == 2: self.sysconfig_vars[u"implementation_lower"] = u"python" confs = {k: (self.system_prefix if v.startswith(self.prefix) else v) for k, v in self.sysconfig_vars.items()} self.system_stdlib = self.sysconfig_path("stdlib", confs) self.system_stdlib_platform = self.sysconfig_path("platstdlib", confs) self.max_size = getattr(sys, "maxsize", getattr(sys, "maxint", None)) self._creators = None def _fast_get_system_executable(self): """Try to get the system executable by just looking at properties""" if self.real_prefix or ( self.base_prefix is not None and self.base_prefix != self.prefix ): # if this is a virtual environment if self.real_prefix is None: base_executable = getattr(sys, "_base_executable", None) # some platforms may set this to help us if base_executable is not None: # use the saved system executable if present if sys.executable != base_executable: # we know we're in a virtual environment, cannot be us return base_executable return None # in this case we just can't tell easily without poking around FS and calling them, bail # if we're not in a virtual environment, this is already a system python, so return the original executable # note we must choose the original and not the pure executable as shim scripts might throw us off return self.original_executable def install_path(self, key): result = self.distutils_install.get(key) if result is None: # use sysconfig if sysconfig_scheme is set or distutils is unavailable # set prefixes to empty => result is relative from cwd prefixes = self.prefix, self.exec_prefix, self.base_prefix, self.base_exec_prefix config_var = {k: "" if v in prefixes else v for k, v in self.sysconfig_vars.items()} result = self.sysconfig_path(key, config_var=config_var).lstrip(os.sep) return result @staticmethod def _distutils_install(): # use distutils primarily because that's what pip does # https://github.com/pypa/pip/blob/main/src/pip/_internal/locations.py#L95 # note here we don't import Distribution directly to allow setuptools to patch it with warnings.catch_warnings(): # disable warning for PEP-632 warnings.simplefilter("ignore") try: from distutils import dist from distutils.command.install import SCHEME_KEYS except ImportError: # if removed or not installed ignore return {} d = dist.Distribution({"script_args": "--no-user-cfg"}) # conf files not parsed so they do not hijack paths if hasattr(sys, "_framework"): sys._framework = None # disable macOS static paths for framework with warnings.catch_warnings(): # disable warning for PEP-632 warnings.simplefilter("ignore") i = d.get_command_obj("install", create=True) i.prefix = os.sep # paths generated are relative to prefix that contains the path sep, this makes it relative i.finalize_options() result = {key: (getattr(i, "install_{}".format(key))[1:]).lstrip(os.sep) for key in SCHEME_KEYS} return result @property def version_str(self): return ".".join(str(i) for i in self.version_info[0:3]) @property def version_release_str(self): return ".".join(str(i) for i in self.version_info[0:2]) @property def python_name(self): version_info = self.version_info return "python{}.{}".format(version_info.major, version_info.minor) @property def is_old_virtualenv(self): return self.real_prefix is not None @property def is_venv(self): return self.base_prefix is not None and self.version_info.major == 3 def sysconfig_path(self, key, config_var=None, sep=os.sep): pattern = self.sysconfig_paths[key] if config_var is None: config_var = self.sysconfig_vars else: base = {k: v for k, v in self.sysconfig_vars.items()} base.update(config_var) config_var = base return pattern.format(**config_var).replace(u"/", sep) def creators(self, refresh=False): if self._creators is None or refresh is True: from virtualenv.run.plugin.creators import CreatorSelector self._creators = CreatorSelector.for_interpreter(self) return self._creators @property def system_include(self): path = self.sysconfig_path( "include", {k: (self.system_prefix if v.startswith(self.prefix) else v) for k, v in self.sysconfig_vars.items()}, ) if not os.path.exists(path): # some broken packaging don't respect the sysconfig, fallback to distutils path # the pattern include the distribution name too at the end, remove that via the parent call fallback = os.path.join(self.prefix, os.path.dirname(self.install_path("headers"))) if os.path.exists(fallback): path = fallback return path @property def system_prefix(self): return self.real_prefix or self.base_prefix or self.prefix @property def system_exec_prefix(self): return self.real_prefix or self.base_exec_prefix or self.exec_prefix def __unicode__(self): content = repr(self) if sys.version_info == 2: content = content.decode("utf-8") return content def __repr__(self): return "{}({!r})".format( self.__class__.__name__, {k: v for k, v in self.__dict__.items() if not k.startswith("_")}, ) def __str__(self): content = "{}({})".format( self.__class__.__name__, ", ".join( "{}={}".format(k, v) for k, v in ( ("spec", self.spec), ( "system" if self.system_executable is not None and self.system_executable != self.executable else None, self.system_executable, ), ( "original" if ( self.original_executable != self.system_executable and self.original_executable != self.executable ) else None, self.original_executable, ), ("exe", self.executable), ("platform", self.platform), ("version", repr(self.version)), ("encoding_fs_io", "{}-{}".format(self.file_system_encoding, self.stdout_encoding)), ) if k is not None ), ) return content @property def spec(self): return "{}{}-{}".format(self.implementation, ".".join(str(i) for i in self.version_info), self.architecture) @classmethod def clear_cache(cls, app_data): # this method is not used by itself, so here and called functions can import stuff locally from virtualenv.discovery.cached_py_info import clear clear(app_data) cls._cache_exe_discovery.clear() def satisfies(self, spec, impl_must_match): """check if a given specification can be satisfied by the this python interpreter instance""" if spec.path: if self.executable == os.path.abspath(spec.path): return True # if the path is a our own executable path we're done if not spec.is_abs: # if path set, and is not our original executable name, this does not match basename = os.path.basename(self.original_executable) spec_path = spec.path if sys.platform == "win32": basename, suffix = os.path.splitext(basename) if spec_path.endswith(suffix): spec_path = spec_path[: -len(suffix)] if basename != spec_path: return False if impl_must_match: if spec.implementation is not None and spec.implementation.lower() != self.implementation.lower(): return False if spec.architecture is not None and spec.architecture != self.architecture: return False for our, req in zip(self.version_info[0:3], (spec.major, spec.minor, spec.micro)): if req is not None and our is not None and our != req: return False return True _current_system = None _current = None @classmethod def current(cls, app_data=None): """ This locates the current host interpreter information. This might be different than what we run into in case the host python has been upgraded from underneath us. """ if cls._current is None: cls._current = cls.from_exe(sys.executable, app_data, raise_on_error=True, resolve_to_host=False) return cls._current @classmethod def current_system(cls, app_data=None): """ This locates the current host interpreter information. This might be different than what we run into in case the host python has been upgraded from underneath us. """ if cls._current_system is None: cls._current_system = cls.from_exe(sys.executable, app_data, raise_on_error=True, resolve_to_host=True) return cls._current_system def _to_json(self): # don't save calculated paths, as these are non primitive types return json.dumps(self._to_dict(), indent=2) def _to_dict(self): data = {var: (getattr(self, var) if var not in ("_creators",) else None) for var in vars(self)} # noinspection PyProtectedMember data["version_info"] = data["version_info"]._asdict() # namedtuple to dictionary return data @classmethod def from_exe(cls, exe, app_data=None, raise_on_error=True, ignore_cache=False, resolve_to_host=True, env=None): """Given a path to an executable get the python information""" # this method is not used by itself, so here and called functions can import stuff locally from virtualenv.discovery.cached_py_info import from_exe env = os.environ if env is None else env proposed = from_exe(cls, app_data, exe, env=env, raise_on_error=raise_on_error, ignore_cache=ignore_cache) # noinspection PyProtectedMember if isinstance(proposed, PythonInfo) and resolve_to_host: try: proposed = proposed._resolve_to_system(app_data, proposed) except Exception as exception: if raise_on_error: raise exception logging.info("ignore %s due cannot resolve system due to %r", proposed.original_executable, exception) proposed = None return proposed @classmethod def _from_json(cls, payload): # the dictionary unroll here is to protect against pypy bug of interpreter crashing raw = json.loads(payload) return cls._from_dict({k: v for k, v in raw.items()}) @classmethod def _from_dict(cls, data): data["version_info"] = VersionInfo(**data["version_info"]) # restore this to a named tuple structure result = cls() result.__dict__ = {k: v for k, v in data.items()} return result @classmethod def _resolve_to_system(cls, app_data, target): start_executable = target.executable prefixes = OrderedDict() while target.system_executable is None: prefix = target.real_prefix or target.base_prefix or target.prefix if prefix in prefixes: if len(prefixes) == 1: # if we're linking back to ourselves accept ourselves with a WARNING logging.info("%r links back to itself via prefixes", target) target.system_executable = target.executable break for at, (p, t) in enumerate(prefixes.items(), start=1): logging.error("%d: prefix=%s, info=%r", at, p, t) logging.error("%d: prefix=%s, info=%r", len(prefixes) + 1, prefix, target) raise RuntimeError("prefixes are causing a circle {}".format("|".join(prefixes.keys()))) prefixes[prefix] = target target = target.discover_exe(app_data, prefix=prefix, exact=False) if target.executable != target.system_executable: target = cls.from_exe(target.system_executable, app_data) target.executable = start_executable return target _cache_exe_discovery = {} def discover_exe(self, app_data, prefix, exact=True, env=None): key = prefix, exact if key in self._cache_exe_discovery and prefix: logging.debug("discover exe from cache %s - exact %s: %r", prefix, exact, self._cache_exe_discovery[key]) return self._cache_exe_discovery[key] logging.debug("discover exe for %s in %s", self, prefix) # we don't know explicitly here, do some guess work - our executable name should tell possible_names = self._find_possible_exe_names() possible_folders = self._find_possible_folders(prefix) discovered = [] env = os.environ if env is None else env for folder in possible_folders: for name in possible_names: info = self._check_exe(app_data, folder, name, exact, discovered, env) if info is not None: self._cache_exe_discovery[key] = info return info if exact is False and discovered: info = self._select_most_likely(discovered, self) folders = os.pathsep.join(possible_folders) self._cache_exe_discovery[key] = info logging.debug("no exact match found, chosen most similar of %s within base folders %s", info, folders) return info msg = "failed to detect {} in {}".format("|".join(possible_names), os.pathsep.join(possible_folders)) raise RuntimeError(msg) def _check_exe(self, app_data, folder, name, exact, discovered, env): exe_path = os.path.join(folder, name) if not os.path.exists(exe_path): return None info = self.from_exe(exe_path, app_data, resolve_to_host=False, raise_on_error=False, env=env) if info is None: # ignore if for some reason we can't query return None for item in ["implementation", "architecture", "version_info"]: found = getattr(info, item) searched = getattr(self, item) if found != searched: if item == "version_info": found, searched = ".".join(str(i) for i in found), ".".join(str(i) for i in searched) executable = info.executable logging.debug("refused interpreter %s because %s differs %s != %s", executable, item, found, searched) if exact is False: discovered.append(info) break else: return info return None @staticmethod def _select_most_likely(discovered, target): # no exact match found, start relaxing our requirements then to facilitate system package upgrades that # could cause this (when using copy strategy of the host python) def sort_by(info): # we need to setup some priority of traits, this is as follows: # implementation, major, minor, micro, architecture, tag, serial matches = [ info.implementation == target.implementation, info.version_info.major == target.version_info.major, info.version_info.minor == target.version_info.minor, info.architecture == target.architecture, info.version_info.micro == target.version_info.micro, info.version_info.releaselevel == target.version_info.releaselevel, info.version_info.serial == target.version_info.serial, ] priority = sum((1 << pos if match else 0) for pos, match in enumerate(reversed(matches))) return priority sorted_discovered = sorted(discovered, key=sort_by, reverse=True) # sort by priority in decreasing order most_likely = sorted_discovered[0] return most_likely def _find_possible_folders(self, inside_folder): candidate_folder = OrderedDict() executables = OrderedDict() executables[os.path.realpath(self.executable)] = None executables[self.executable] = None executables[os.path.realpath(self.original_executable)] = None executables[self.original_executable] = None for exe in executables.keys(): base = os.path.dirname(exe) # following path pattern of the current if base.startswith(self.prefix): relative = base[len(self.prefix) :] candidate_folder["{}{}".format(inside_folder, relative)] = None # or at root level candidate_folder[inside_folder] = None return list(i for i in candidate_folder.keys() if os.path.exists(i)) def _find_possible_exe_names(self): name_candidate = OrderedDict() for name in self._possible_base(): for at in (3, 2, 1, 0): version = ".".join(str(i) for i in self.version_info[:at]) for arch in ["-{}".format(self.architecture), ""]: for ext in EXTENSIONS: candidate = "{}{}{}{}".format(name, version, arch, ext) name_candidate[candidate] = None return list(name_candidate.keys()) def _possible_base(self): possible_base = OrderedDict() basename = os.path.splitext(os.path.basename(self.executable))[0].rstrip(digits) possible_base[basename] = None possible_base[self.implementation] = None # python is always the final option as in practice is used by multiple implementation as exe name if "python" in possible_base: del possible_base["python"] possible_base["python"] = None for base in possible_base: lower = base.lower() yield lower from virtualenv.info import fs_is_case_sensitive if fs_is_case_sensitive(): if base != lower: yield base upper = base.upper() if upper != base: yield upper if __name__ == "__main__": # dump a JSON representation of the current python # noinspection PyProtectedMember print(PythonInfo()._to_json())
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