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projecten1/lib/python3.6/site-packages/wheel/install.py

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+"""
+Operations on existing wheel files, including basic installation.
+"""
+# XXX see patched pip to install
+
+from __future__ import print_function
+
+import csv
+import hashlib
+import os.path
+import re
+import shutil
+import sys
+import warnings
+import zipfile
+
+from . import signatures
+from .paths import get_install_paths
+from .pep425tags import get_supported
+from .pkginfo import read_pkg_info_bytes
+from .util import (
+    urlsafe_b64encode, from_json, urlsafe_b64decode, native, binary, HashingFile, open_for_csv)
+
+try:
+    _big_number = sys.maxsize
+except NameError:
+    _big_number = sys.maxint
+
+# The next major version after this version of the 'wheel' tool:
+VERSION_TOO_HIGH = (1, 0)
+
+# Non-greedy matching of an optional build number may be too clever (more
+# invalid wheel filenames will match). Separate regex for .dist-info?
+WHEEL_INFO_RE = re.compile(
+    r"""^(?P<namever>(?P<name>.+?)-(?P<ver>\d.*?))(-(?P<build>\d.*?))?
+     -(?P<pyver>[a-z].+?)-(?P<abi>.+?)-(?P<plat>.+?)(\.whl|\.dist-info)$""",
+    re.VERBOSE).match
+
+
+def parse_version(version):
+    """Use parse_version from pkg_resources or distutils as available."""
+    global parse_version
+    try:
+        from pkg_resources import parse_version
+    except ImportError:
+        from distutils.version import LooseVersion as parse_version
+    return parse_version(version)
+
+
+class reify(object):
+    """Put the result of a method which uses this (non-data)
+    descriptor decorator in the instance dict after the first call,
+    effectively replacing the decorator with an instance variable.
+    """
+
+    def __init__(self, wrapped):
+        self.wrapped = wrapped
+        self.__doc__ = wrapped.__doc__
+
+    def __get__(self, inst, objtype=None):
+        if inst is None:
+            return self
+        val = self.wrapped(inst)
+        setattr(inst, self.wrapped.__name__, val)
+        return val
+
+
+class BadWheelFile(ValueError):
+    pass
+
+
+class WheelFile(object):
+    """Parse wheel-specific attributes from a wheel (.whl) file and offer
+    basic installation and verification support.
+
+    WheelFile can be used to simply parse a wheel filename by avoiding the
+    methods that require the actual file contents."""
+
+    WHEEL_INFO = "WHEEL"
+    RECORD = "RECORD"
+
+    def __init__(self,
+                 filename,
+                 fp=None,
+                 append=False,
+                 context=get_supported):
+        """
+        :param fp: A seekable file-like object or None to open(filename).
+        :param append: Open archive in append mode.
+        :param context: Function returning list of supported tags. Wheels
+        must have the same context to be sortable.
+        """
+        self.filename = filename
+        self.fp = fp
+        self.append = append
+        self.context = context
+        basename = os.path.basename(filename)
+        self.parsed_filename = WHEEL_INFO_RE(basename)
+        if not basename.endswith('.whl') or self.parsed_filename is None:
+            raise BadWheelFile("Bad filename '%s'" % filename)
+
+    def __repr__(self):
+        return self.filename
+
+    @property
+    def distinfo_name(self):
+        return "%s.dist-info" % self.parsed_filename.group('namever')
+
+    @property
+    def datadir_name(self):
+        return "%s.data" % self.parsed_filename.group('namever')
+
+    @property
+    def record_name(self):
+        return "%s/%s" % (self.distinfo_name, self.RECORD)
+
+    @property
+    def wheelinfo_name(self):
+        return "%s/%s" % (self.distinfo_name, self.WHEEL_INFO)
+
+    @property
+    def tags(self):
+        """A wheel file is compatible with the Cartesian product of the
+        period-delimited tags in its filename.
+        To choose a wheel file among several candidates having the same
+        distribution version 'ver', an installer ranks each triple of
+        (pyver, abi, plat) that its Python installation can run, sorting
+        the wheels by the best-ranked tag it supports and then by their
+        arity which is just len(list(compatibility_tags)).
+        """
+        tags = self.parsed_filename.groupdict()
+        for pyver in tags['pyver'].split('.'):
+            for abi in tags['abi'].split('.'):
+                for plat in tags['plat'].split('.'):
+                    yield (pyver, abi, plat)
+
+    compatibility_tags = tags
+
+    @property
+    def arity(self):
+        """The number of compatibility tags the wheel declares."""
+        return len(list(self.compatibility_tags))
+
+    @property
+    def rank(self):
+        """
+        Lowest index of any of this wheel's tags in self.context(), and the
+        arity e.g. (0, 1)
+        """
+        return self.compatibility_rank(self.context())
+
+    @property
+    def compatible(self):
+        return self.rank[0] != _big_number  # bad API!
+
+    # deprecated:
+    def compatibility_rank(self, supported):
+        """Rank the wheel against the supported tags. Smaller ranks are more
+        compatible!
+
+        :param supported: A list of compatibility tags that the current
+            Python implemenation can run.
+        """
+        preferences = []
+        for tag in self.compatibility_tags:
+            try:
+                preferences.append(supported.index(tag))
+            # Tag not present
+            except ValueError:
+                pass
+        if len(preferences):
+            return (min(preferences), self.arity)
+        return (_big_number, 0)
+
+    # deprecated
+    def supports_current_python(self, x):
+        assert self.context == x, 'context mismatch'
+        return self.compatible
+
+    # Comparability.
+    # Wheels are equal if they refer to the same file.
+    # If two wheels are not equal, compare based on (in this order):
+    #   1. Name
+    #   2. Version
+    #   3. Compatibility rank
+    #   4. Filename (as a tiebreaker)
+    @property
+    def _sort_key(self):
+        return (self.parsed_filename.group('name'),
+                parse_version(self.parsed_filename.group('ver')),
+                tuple(-x for x in self.rank),
+                self.filename)
+
+    def __eq__(self, other):
+        return self.filename == other.filename
+
+    def __ne__(self, other):
+        return self.filename != other.filename
+
+    def __lt__(self, other):
+        if self.context != other.context:
+            raise TypeError("{0}.context != {1}.context".format(self, other))
+
+        return self._sort_key < other._sort_key
+
+        # XXX prune
+
+        sn = self.parsed_filename.group('name')
+        on = other.parsed_filename.group('name')
+        if sn != on:
+            return sn < on
+        sv = parse_version(self.parsed_filename.group('ver'))
+        ov = parse_version(other.parsed_filename.group('ver'))
+        if sv != ov:
+            return sv < ov
+        # Compatibility
+        if self.context != other.context:
+            raise TypeError("{0}.context != {1}.context".format(self, other))
+        sc = self.rank
+        oc = other.rank
+        if sc is not None and oc is not None and sc != oc:
+            # Smaller compatibility ranks are "better" than larger ones,
+            # so we have to reverse the sense of the comparison here!
+            return sc > oc
+        elif sc is None and oc is not None:
+            return False
+        return self.filename < other.filename
+
+    def __gt__(self, other):
+        return other < self
+
+    def __le__(self, other):
+        return self == other or self < other
+
+    def __ge__(self, other):
+        return self == other or other < self
+
+    #
+    # Methods using the file's contents:
+    #
+
+    @reify
+    def zipfile(self):
+        mode = "r"
+        if self.append:
+            mode = "a"
+        vzf = VerifyingZipFile(self.fp if self.fp else self.filename, mode)
+        if not self.append:
+            self.verify(vzf)
+        return vzf
+
+    @reify
+    def parsed_wheel_info(self):
+        """Parse wheel metadata (the .data/WHEEL file)"""
+        return read_pkg_info_bytes(self.zipfile.read(self.wheelinfo_name))
+
+    def check_version(self):
+        version = self.parsed_wheel_info['Wheel-Version']
+        if tuple(map(int, version.split('.'))) >= VERSION_TOO_HIGH:
+            raise ValueError("Wheel version is too high")
+
+    @reify
+    def install_paths(self):
+        """
+        Consult distutils to get the install paths for our dist.  A dict with
+        ('purelib', 'platlib', 'headers', 'scripts', 'data').
+
+        We use the name from our filename as the dist name, which means headers
+        could be installed in the wrong place if the filesystem-escaped name
+        is different than the Name.  Who cares?
+        """
+        name = self.parsed_filename.group('name')
+        return get_install_paths(name)
+
+    def install(self, force=False, overrides={}):
+        """
+        Install the wheel into site-packages.
+        """
+
+        # Utility to get the target directory for a particular key
+        def get_path(key):
+            return overrides.get(key) or self.install_paths[key]
+
+        # The base target location is either purelib or platlib
+        if self.parsed_wheel_info['Root-Is-Purelib'] == 'true':
+            root = get_path('purelib')
+        else:
+            root = get_path('platlib')
+
+        # Parse all the names in the archive
+        name_trans = {}
+        for info in self.zipfile.infolist():
+            name = info.filename
+            # Zip files can contain entries representing directories.
+            # These end in a '/'.
+            # We ignore these, as we create directories on demand.
+            if name.endswith('/'):
+                continue
+
+            # Pathnames in a zipfile namelist are always /-separated.
+            # In theory, paths could start with ./ or have other oddities
+            # but this won't happen in practical cases of well-formed wheels.
+            # We'll cover the simple case of an initial './' as it's both easy
+            # to do and more common than most other oddities.
+            if name.startswith('./'):
+                name = name[2:]
+
+            # Split off the base directory to identify files that are to be
+            # installed in non-root locations
+            basedir, sep, filename = name.partition('/')
+            if sep and basedir == self.datadir_name:
+                # Data file. Target destination is elsewhere
+                key, sep, filename = filename.partition('/')
+                if not sep:
+                    raise ValueError("Invalid filename in wheel: {0}".format(name))
+                target = get_path(key)
+            else:
+                # Normal file. Target destination is root
+                key = ''
+                target = root
+                filename = name
+
+            # Map the actual filename from the zipfile to its intended target
+            # directory and the pathname relative to that directory.
+            dest = os.path.normpath(os.path.join(target, filename))
+            name_trans[info] = (key, target, filename, dest)
+
+        # We're now ready to start processing the actual install. The process
+        # is as follows:
+        #   1. Prechecks - is the wheel valid, is its declared architecture
+        #      OK, etc. [[Responsibility of the caller]]
+        #   2. Overwrite check - do any of the files to be installed already
+        #      exist?
+        #   3. Actual install - put the files in their target locations.
+        #   4. Update RECORD - write a suitably modified RECORD file to
+        #      reflect the actual installed paths.
+
+        if not force:
+            for info, v in name_trans.items():
+                k = info.filename
+                key, target, filename, dest = v
+                if os.path.exists(dest):
+                    raise ValueError(
+                        "Wheel file {0} would overwrite {1}. Use force if this is intended".format(
+                            k, dest))
+
+        # Get the name of our executable, for use when replacing script
+        # wrapper hashbang lines.
+        # We encode it using getfilesystemencoding, as that is "the name of
+        # the encoding used to convert Unicode filenames into system file
+        # names".
+        exename = sys.executable.encode(sys.getfilesystemencoding())
+        record_data = []
+        record_name = self.distinfo_name + '/RECORD'
+        for info, (key, target, filename, dest) in name_trans.items():
+            name = info.filename
+            source = self.zipfile.open(info)
+            # Skip the RECORD file
+            if name == record_name:
+                continue
+            ddir = os.path.dirname(dest)
+            if not os.path.isdir(ddir):
+                os.makedirs(ddir)
+
+            temp_filename = dest + '.part'
+            try:
+                with HashingFile(temp_filename, 'wb') as destination:
+                    if key == 'scripts':
+                        hashbang = source.readline()
+                        if hashbang.startswith(b'#!python'):
+                            hashbang = b'#!' + exename + binary(os.linesep)
+                        destination.write(hashbang)
+
+                    shutil.copyfileobj(source, destination)
+            except BaseException:
+                if os.path.exists(temp_filename):
+                    os.unlink(temp_filename)
+
+                raise
+
+            os.rename(temp_filename, dest)
+            reldest = os.path.relpath(dest, root)
+            reldest.replace(os.sep, '/')
+            record_data.append((reldest, destination.digest(), destination.length))
+            destination.close()
+            source.close()
+            # preserve attributes (especially +x bit for scripts)
+            attrs = info.external_attr >> 16
+            if attrs:  # tends to be 0 if Windows.
+                os.chmod(dest, info.external_attr >> 16)
+
+        record_name = os.path.join(root, self.record_name)
+        with open_for_csv(record_name, 'w+') as record_file:
+            writer = csv.writer(record_file)
+            for reldest, digest, length in sorted(record_data):
+                writer.writerow((reldest, digest, length))
+            writer.writerow((self.record_name, '', ''))
+
+    def verify(self, zipfile=None):
+        """Configure the VerifyingZipFile `zipfile` by verifying its signature
+        and setting expected hashes for every hash in RECORD.
+        Caller must complete the verification process by completely reading
+        every file in the archive (e.g. with extractall)."""
+        sig = None
+        if zipfile is None:
+            zipfile = self.zipfile
+        zipfile.strict = True
+
+        record_name = '/'.join((self.distinfo_name, 'RECORD'))
+        sig_name = '/'.join((self.distinfo_name, 'RECORD.jws'))
+        # tolerate s/mime signatures:
+        smime_sig_name = '/'.join((self.distinfo_name, 'RECORD.p7s'))
+        zipfile.set_expected_hash(record_name, None)
+        zipfile.set_expected_hash(sig_name, None)
+        zipfile.set_expected_hash(smime_sig_name, None)
+        record = zipfile.read(record_name)
+
+        record_digest = urlsafe_b64encode(hashlib.sha256(record).digest())
+        try:
+            sig = from_json(native(zipfile.read(sig_name)))
+        except KeyError:  # no signature
+            pass
+        if sig:
+            headers, payload = signatures.verify(sig)
+            if payload['hash'] != "sha256=" + native(record_digest):
+                msg = "RECORD.jws claimed RECORD hash {} != computed hash {}."
+                raise BadWheelFile(msg.format(payload['hash'],
+                                              native(record_digest)))
+
+        reader = csv.reader((native(r, 'utf-8') for r in record.splitlines()))
+
+        for row in reader:
+            filename = row[0]
+            hash = row[1]
+            if not hash:
+                if filename not in (record_name, sig_name):
+                    print("%s has no hash!" % filename, file=sys.stderr)
+                continue
+
+            algo, data = row[1].split('=', 1)
+            assert algo == "sha256", "Unsupported hash algorithm"
+            zipfile.set_expected_hash(filename, urlsafe_b64decode(binary(data)))
+
+
+class VerifyingZipFile(zipfile.ZipFile):
+    """ZipFile that can assert that each of its extracted contents matches
+    an expected sha256 hash. Note that each file must be completely read in
+    order for its hash to be checked."""
+
+    def __init__(self, file, mode="r",
+                 compression=zipfile.ZIP_STORED,
+                 allowZip64=True):
+        super(VerifyingZipFile, self).__init__(file, mode, compression, allowZip64)
+
+        self.strict = False
+        self._expected_hashes = {}
+        self._hash_algorithm = hashlib.sha256
+
+    def set_expected_hash(self, name, hash):
+        """
+        :param name: name of zip entry
+        :param hash: bytes of hash (or None for "don't care")
+        """
+        self._expected_hashes[name] = hash
+
+    def open(self, name_or_info, mode="r", pwd=None):
+        """Return file-like object for 'name'."""
+        # A non-monkey-patched version would contain most of zipfile.py
+        ef = super(VerifyingZipFile, self).open(name_or_info, mode, pwd)
+        if isinstance(name_or_info, zipfile.ZipInfo):
+            name = name_or_info.filename
+        else:
+            name = name_or_info
+
+        if name in self._expected_hashes and self._expected_hashes[name] is not None:
+            expected_hash = self._expected_hashes[name]
+            try:
+                _update_crc_orig = ef._update_crc
+            except AttributeError:
+                warnings.warn('Need ZipExtFile._update_crc to implement '
+                              'file hash verification (in Python >= 2.7)')
+                return ef
+            running_hash = self._hash_algorithm()
+            if hasattr(ef, '_eof'):  # py33
+                def _update_crc(data):
+                    _update_crc_orig(data)
+                    running_hash.update(data)
+                    if ef._eof and running_hash.digest() != expected_hash:
+                        raise BadWheelFile("Bad hash for file %r" % ef.name)
+            else:
+                def _update_crc(data, eof=None):
+                    _update_crc_orig(data, eof=eof)
+                    running_hash.update(data)
+                    if eof and running_hash.digest() != expected_hash:
+                        raise BadWheelFile("Bad hash for file %r" % ef.name)
+            ef._update_crc = _update_crc
+        elif self.strict and name not in self._expected_hashes:
+            raise BadWheelFile("No expected hash for file %r" % ef.name)
+        return ef
+
+    def pop(self):
+        """Truncate the last file off this zipfile.
+        Assumes infolist() is in the same order as the files (true for
+        ordinary zip files created by Python)"""
+        if not self.fp:
+            raise RuntimeError(
+                  "Attempt to pop from ZIP archive that was already closed")
+        last = self.infolist().pop()
+        del self.NameToInfo[last.filename]
+        self.fp.seek(last.header_offset, os.SEEK_SET)
+        self.fp.truncate()
+        self._didModify = True