"""Support functions for working with wheel files.
"""
from __future__ import absolute_import
import logging
from email.parser import Parser
from zipfile import ZipFile
from pip._vendor.packaging.utils import canonicalize_name
from pip._vendor.pkg_resources import DistInfoDistribution
from pip._vendor.six import PY2, ensure_str
from pip._internal.exceptions import UnsupportedWheel
from pip._internal.utils.pkg_resources import DictMetadata
from pip._internal.utils.typing import MYPY_CHECK_RUNNING
if MYPY_CHECK_RUNNING:
from email.message import Message
from typing import Dict, Tuple
from pip._vendor.pkg_resources import Distribution
if PY2:
from zipfile import BadZipfile as BadZipFile
else:
from zipfile import BadZipFile
VERSION_COMPATIBLE = (1, 0)
logger = logging.getLogger(__name__)
class WheelMetadata(DictMetadata):
"""Metadata provider that maps metadata decoding exceptions to our
internal exception type.
"""
def __init__(self, metadata, wheel_name):
# type: (Dict[str, bytes], str) -> None
super(WheelMetadata, self).__init__(metadata)
self._wheel_name = wheel_name
def get_metadata(self, name):
# type: (str) -> str
try:
return super(WheelMetadata, self).get_metadata(name)
except UnicodeDecodeError as e:
# Augment the default error with the origin of the file.
raise UnsupportedWheel(
"Error decoding metadata for {}: {}".format(
self._wheel_name, e
)
)
def pkg_resources_distribution_for_wheel(wheel_zip, name, location):
# type: (ZipFile, str, str) -> Distribution
"""Get a pkg_resources distribution given a wheel.
:raises UnsupportedWheel: on any errors
"""
info_dir, _ = parse_wheel(wheel_zip, name)
metadata_files = [
p for p in wheel_zip.namelist() if p.startswith("{}/".format(info_dir))
]
metadata_text = {} # type: Dict[str, bytes]
for path in metadata_files:
# If a flag is set, namelist entries may be unicode in Python 2.
# We coerce them to native str type to match the types used in the rest
# of the code. This cannot fail because unicode can always be encoded
# with UTF-8.
full_path = ensure_str(path)
_, metadata_name = full_path.split("/", 1)
try:
metadata_text[metadata_name] = read_wheel_metadata_file(
wheel_zip, full_path
)
except UnsupportedWheel as e:
raise UnsupportedWheel(
"{} has an invalid wheel, {}".format(name, str(e))
)
metadata = WheelMetadata(metadata_text, location)
return DistInfoDistribution(
location=location, metadata=metadata, project_name=name
)
def parse_wheel(wheel_zip, name):
# type: (ZipFile, str) -> Tuple[str, Message]
"""Extract information from the provided wheel, ensuring it meets basic
standards.
Returns the name of the .dist-info directory and the parsed WHEEL metadata.
"""
try:
info_dir = wheel_dist_info_dir(wheel_zip, name)
metadata = wheel_metadata(wheel_zip, info_dir)
version = wheel_version(metadata)
except UnsupportedWheel as e:
raise UnsupportedWheel(
"{} has an invalid wheel, {}".format(name, str(e))
)
check_compatibility(version, name)
return info_dir, metadata
def wheel_dist_info_dir(source, name):
# type: (ZipFile, str) -> str
"""Returns the name of the contained .dist-info directory.
Raises AssertionError or UnsupportedWheel if not found, >1 found, or
it doesn't match the provided name.
"""
# Zip file path separators must be /
subdirs = set(p.split("/", 1)[0] for p in source.namelist())
info_dirs = [s for s in subdirs if s.endswith('.dist-info')]
if not info_dirs:
raise UnsupportedWheel(".dist-info directory not found")
if len(info_dirs) > 1:
raise UnsupportedWheel(
"multiple .dist-info directories found: {}".format(
", ".join(info_dirs)
)
)
info_dir = info_dirs[0]
info_dir_name = canonicalize_name(info_dir)
canonical_name = canonicalize_name(name)
if not info_dir_name.startswith(canonical_name):
raise UnsupportedWheel(
".dist-info directory {!r} does not start with {!r}".format(
info_dir, canonical_name
)
)
# Zip file paths can be unicode or str depending on the zip entry flags,
# so normalize it.
return ensure_str(info_dir)
def read_wheel_metadata_file(source, path):
# type: (ZipFile, str) -> bytes
try:
return source.read(path)
# BadZipFile for general corruption, KeyError for missing entry,
# and RuntimeError for password-protected files
except (BadZipFile, KeyError, RuntimeError) as e:
raise UnsupportedWheel(
"could not read {!r} file: {!r}".format(path, e)
)
def wheel_metadata(source, dist_info_dir):
# type: (ZipFile, str) -> Message
"""Return the WHEEL metadata of an extracted wheel, if possible.
Otherwise, raise UnsupportedWheel.
"""
path = "{}/WHEEL".format(dist_info_dir)
# Zip file path separators must be /
wheel_contents = read_wheel_metadata_file(source, path)
try:
wheel_text = ensure_str(wheel_contents)
except UnicodeDecodeError as e:
raise UnsupportedWheel("error decoding {!r}: {!r}".format(path, e))
# FeedParser (used by Parser) does not raise any exceptions. The returned
# message may have .defects populated, but for backwards-compatibility we
# currently ignore them.
return Parser().parsestr(wheel_text)
def wheel_version(wheel_data):
# type: (Message) -> Tuple[int, ...]
"""Given WHEEL metadata, return the parsed Wheel-Version.
Otherwise, raise UnsupportedWheel.
"""
version_text = wheel_data["Wheel-Version"]
if version_text is None:
raise UnsupportedWheel("WHEEL is missing Wheel-Version")
version = version_text.strip()
try:
return tuple(map(int, version.split('.')))
except ValueError:
raise UnsupportedWheel("invalid Wheel-Version: {!r}".format(version))
def check_compatibility(version, name):
# type: (Tuple[int, ...], str) -> None
"""Raises errors or warns if called with an incompatible Wheel-Version.
pip should refuse to install a Wheel-Version that's a major series
ahead of what it's compatible with (e.g 2.0 > 1.1); and warn when
installing a version only minor version ahead (e.g 1.2 > 1.1).
version: a 2-tuple representing a Wheel-Version (Major, Minor)
name: name of wheel or package to raise exception about
:raises UnsupportedWheel: when an incompatible Wheel-Version is given
"""
if version[0] > VERSION_COMPATIBLE[0]:
raise UnsupportedWheel(
"{}'s Wheel-Version ({}) is not compatible with this version "
"of pip".format(name, '.'.join(map(str, version)))
)
elif version > VERSION_COMPATIBLE:
logger.warning(
'Installing from a newer Wheel-Version (%s)',
'.'.join(map(str, version)),
)