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			629 lines
		
	
	
	
		
			23 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			629 lines
		
	
	
	
		
			23 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| """PEP 376 implementation."""
 | |
| 
 | |
| import io
 | |
| import os
 | |
| import re
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| import csv
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| import sys
 | |
| import zipimport
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| from hashlib import md5
 | |
| from packaging import logger
 | |
| from packaging.errors import PackagingError
 | |
| from packaging.version import suggest_normalized_version, VersionPredicate
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| from packaging.metadata import Metadata
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| 
 | |
| 
 | |
| __all__ = [
 | |
|     'Distribution', 'EggInfoDistribution', 'distinfo_dirname',
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|     'get_distributions', 'get_distribution', 'get_file_users',
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|     'provides_distribution', 'obsoletes_distribution',
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|     'enable_cache', 'disable_cache', 'clear_cache',
 | |
| ]
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| 
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| 
 | |
| # TODO update docs
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| 
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| DIST_FILES = ('INSTALLER', 'METADATA', 'RECORD', 'REQUESTED', 'RESOURCES')
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| 
 | |
| # Cache
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| _cache_name = {}  # maps names to Distribution instances
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| _cache_name_egg = {}  # maps names to EggInfoDistribution instances
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| _cache_path = {}  # maps paths to Distribution instances
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| _cache_path_egg = {}  # maps paths to EggInfoDistribution instances
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| _cache_generated = False  # indicates if .dist-info distributions are cached
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| _cache_generated_egg = False  # indicates if .dist-info and .egg are cached
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| _cache_enabled = True
 | |
| 
 | |
| 
 | |
| def enable_cache():
 | |
|     """
 | |
|     Enables the internal cache.
 | |
| 
 | |
|     Note that this function will not clear the cache in any case, for that
 | |
|     functionality see :func:`clear_cache`.
 | |
|     """
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|     global _cache_enabled
 | |
| 
 | |
|     _cache_enabled = True
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| 
 | |
| 
 | |
| def disable_cache():
 | |
|     """
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|     Disables the internal cache.
 | |
| 
 | |
|     Note that this function will not clear the cache in any case, for that
 | |
|     functionality see :func:`clear_cache`.
 | |
|     """
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|     global _cache_enabled
 | |
| 
 | |
|     _cache_enabled = False
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| 
 | |
| 
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| def clear_cache():
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|     """ Clears the internal cache. """
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|     global _cache_name, _cache_name_egg, _cache_path, _cache_path_egg, \
 | |
|         _cache_generated, _cache_generated_egg
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| 
 | |
|     _cache_name = {}
 | |
|     _cache_name_egg = {}
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|     _cache_path = {}
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|     _cache_path_egg = {}
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|     _cache_generated = False
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|     _cache_generated_egg = False
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| 
 | |
| 
 | |
| def _yield_distributions(include_dist, include_egg, paths=sys.path):
 | |
|     """
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|     Yield .dist-info and .egg(-info) distributions, based on the arguments
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| 
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|     :parameter include_dist: yield .dist-info distributions
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|     :parameter include_egg: yield .egg(-info) distributions
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|     """
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|     for path in paths:
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|         realpath = os.path.realpath(path)
 | |
|         if not os.path.isdir(realpath):
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|             continue
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|         for dir in os.listdir(realpath):
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|             dist_path = os.path.join(realpath, dir)
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|             if include_dist and dir.endswith('.dist-info'):
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|                 yield Distribution(dist_path)
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|             elif include_egg and (dir.endswith('.egg-info') or
 | |
|                                   dir.endswith('.egg')):
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|                 yield EggInfoDistribution(dist_path)
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| 
 | |
| 
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| def _generate_cache(use_egg_info=False, paths=sys.path):
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|     global _cache_generated, _cache_generated_egg
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| 
 | |
|     if _cache_generated_egg or (_cache_generated and not use_egg_info):
 | |
|         return
 | |
|     else:
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|         gen_dist = not _cache_generated
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|         gen_egg = use_egg_info
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| 
 | |
|         for dist in _yield_distributions(gen_dist, gen_egg, paths):
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|             if isinstance(dist, Distribution):
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|                 _cache_path[dist.path] = dist
 | |
|                 if not dist.name in _cache_name:
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|                     _cache_name[dist.name] = []
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|                 _cache_name[dist.name].append(dist)
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|             else:
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|                 _cache_path_egg[dist.path] = dist
 | |
|                 if not dist.name in _cache_name_egg:
 | |
|                     _cache_name_egg[dist.name] = []
 | |
|                 _cache_name_egg[dist.name].append(dist)
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| 
 | |
|         if gen_dist:
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|             _cache_generated = True
 | |
|         if gen_egg:
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|             _cache_generated_egg = True
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| 
 | |
| 
 | |
| class Distribution:
 | |
|     """Created with the *path* of the ``.dist-info`` directory provided to the
 | |
|     constructor. It reads the metadata contained in ``METADATA`` when it is
 | |
|     instantiated."""
 | |
| 
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|     name = ''
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|     """The name of the distribution."""
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| 
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|     version = ''
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|     """The version of the distribution."""
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| 
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|     metadata = None
 | |
|     """A :class:`packaging.metadata.Metadata` instance loaded with
 | |
|     the distribution's ``METADATA`` file."""
 | |
| 
 | |
|     requested = False
 | |
|     """A boolean that indicates whether the ``REQUESTED`` metadata file is
 | |
|     present (in other words, whether the package was installed by user
 | |
|     request or it was installed as a dependency)."""
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| 
 | |
|     def __init__(self, path):
 | |
|         if _cache_enabled and path in _cache_path:
 | |
|             self.metadata = _cache_path[path].metadata
 | |
|         else:
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|             metadata_path = os.path.join(path, 'METADATA')
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|             self.metadata = Metadata(path=metadata_path)
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| 
 | |
|         self.name = self.metadata['Name']
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|         self.version = self.metadata['Version']
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|         self.path = path
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| 
 | |
|         if _cache_enabled and not path in _cache_path:
 | |
|             _cache_path[path] = self
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| 
 | |
|     def __repr__(self):
 | |
|         return '<Distribution %r %s at %r>' % (
 | |
|             self.name, self.version, self.path)
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| 
 | |
|     def _get_records(self, local=False):
 | |
|         with self.get_distinfo_file('RECORD') as record:
 | |
|             record_reader = csv.reader(record, delimiter=',',
 | |
|                                        lineterminator='\n')
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|             # XXX needs an explaining comment
 | |
|             for row in record_reader:
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|                 path, checksum, size = (row[:] +
 | |
|                                         [None for i in range(len(row), 3)])
 | |
|                 if local:
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|                     path = path.replace('/', os.sep)
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|                     path = os.path.join(sys.prefix, path)
 | |
|                 yield path, checksum, size
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| 
 | |
|     def get_resource_path(self, relative_path):
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|         with self.get_distinfo_file('RESOURCES') as resources_file:
 | |
|             resources_reader = csv.reader(resources_file, delimiter=',',
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|                                            lineterminator='\n')
 | |
|             for relative, destination in resources_reader:
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|                 if relative == relative_path:
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|                     return destination
 | |
|         raise KeyError(
 | |
|             'no resource file with relative path %r is installed' %
 | |
|             relative_path)
 | |
| 
 | |
|     def list_installed_files(self, local=False):
 | |
|         """
 | |
|         Iterates over the ``RECORD`` entries and returns a tuple
 | |
|         ``(path, md5, size)`` for each line. If *local* is ``True``,
 | |
|         the returned path is transformed into a local absolute path.
 | |
|         Otherwise the raw value from RECORD is returned.
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| 
 | |
|         A local absolute path is an absolute path in which occurrences of
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|         ``'/'`` have been replaced by the system separator given by ``os.sep``.
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| 
 | |
|         :parameter local: flag to say if the path should be returned a local
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|                           absolute path
 | |
| 
 | |
|         :type local: boolean
 | |
|         :returns: iterator of (path, md5, size)
 | |
|         """
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|         return self._get_records(local)
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| 
 | |
|     def uses(self, path):
 | |
|         """
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|         Returns ``True`` if path is listed in ``RECORD``. *path* can be a local
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|         absolute path or a relative ``'/'``-separated path.
 | |
| 
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|         :rtype: boolean
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|         """
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|         for p, checksum, size in self._get_records():
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|             local_absolute = os.path.join(sys.prefix, p)
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|             if path == p or path == local_absolute:
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|                 return True
 | |
|         return False
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| 
 | |
|     def get_distinfo_file(self, path, binary=False):
 | |
|         """
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|         Returns a file located under the ``.dist-info`` directory. Returns a
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|         ``file`` instance for the file pointed by *path*.
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| 
 | |
|         :parameter path: a ``'/'``-separated path relative to the
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|                          ``.dist-info`` directory or an absolute path;
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|                          If *path* is an absolute path and doesn't start
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|                          with the ``.dist-info`` directory path,
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|                          a :class:`PackagingError` is raised
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|         :type path: string
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|         :parameter binary: If *binary* is ``True``, opens the file in read-only
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|                            binary mode (``rb``), otherwise opens it in
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|                            read-only mode (``r``).
 | |
|         :rtype: file object
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|         """
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|         open_flags = 'r'
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|         if binary:
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|             open_flags += 'b'
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| 
 | |
|         # Check if it is an absolute path  # XXX use relpath, add tests
 | |
|         if path.find(os.sep) >= 0:
 | |
|             # it's an absolute path?
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|             distinfo_dirname, path = path.split(os.sep)[-2:]
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|             if distinfo_dirname != self.path.split(os.sep)[-1]:
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|                 raise PackagingError(
 | |
|                     'dist-info file %r does not belong to the %r %s '
 | |
|                     'distribution' % (path, self.name, self.version))
 | |
| 
 | |
|         # The file must be relative
 | |
|         if path not in DIST_FILES:
 | |
|             raise PackagingError('invalid path for a dist-info file: %r' %
 | |
|                                  path)
 | |
| 
 | |
|         path = os.path.join(self.path, path)
 | |
|         return open(path, open_flags)
 | |
| 
 | |
|     def list_distinfo_files(self, local=False):
 | |
|         """
 | |
|         Iterates over the ``RECORD`` entries and returns paths for each line if
 | |
|         the path is pointing to a file located in the ``.dist-info`` directory
 | |
|         or one of its subdirectories.
 | |
| 
 | |
|         :parameter local: If *local* is ``True``, each returned path is
 | |
|                           transformed into a local absolute path. Otherwise the
 | |
|                           raw value from ``RECORD`` is returned.
 | |
|         :type local: boolean
 | |
|         :returns: iterator of paths
 | |
|         """
 | |
|         for path, checksum, size in self._get_records(local):
 | |
|             yield path
 | |
| 
 | |
|     def __eq__(self, other):
 | |
|         return isinstance(other, Distribution) and self.path == other.path
 | |
| 
 | |
|     # See http://docs.python.org/reference/datamodel#object.__hash__
 | |
|     __hash__ = object.__hash__
 | |
| 
 | |
| 
 | |
| class EggInfoDistribution:
 | |
|     """Created with the *path* of the ``.egg-info`` directory or file provided
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|     to the constructor. It reads the metadata contained in the file itself, or
 | |
|     if the given path happens to be a directory, the metadata is read from the
 | |
|     file ``PKG-INFO`` under that directory."""
 | |
| 
 | |
|     name = ''
 | |
|     """The name of the distribution."""
 | |
| 
 | |
|     version = ''
 | |
|     """The version of the distribution."""
 | |
| 
 | |
|     metadata = None
 | |
|     """A :class:`packaging.metadata.Metadata` instance loaded with
 | |
|     the distribution's ``METADATA`` file."""
 | |
| 
 | |
|     _REQUIREMENT = re.compile(
 | |
|         r'(?P<name>[-A-Za-z0-9_.]+)\s*'
 | |
|         r'(?P<first>(?:<|<=|!=|==|>=|>)[-A-Za-z0-9_.]+)?\s*'
 | |
|         r'(?P<rest>(?:\s*,\s*(?:<|<=|!=|==|>=|>)[-A-Za-z0-9_.]+)*)\s*'
 | |
|         r'(?P<extras>\[.*\])?')
 | |
| 
 | |
|     def __init__(self, path):
 | |
|         self.path = path
 | |
|         if _cache_enabled and path in _cache_path_egg:
 | |
|             self.metadata = _cache_path_egg[path].metadata
 | |
|             self.name = self.metadata['Name']
 | |
|             self.version = self.metadata['Version']
 | |
|             return
 | |
| 
 | |
|         # reused from Distribute's pkg_resources
 | |
|         def yield_lines(strs):
 | |
|             """Yield non-empty/non-comment lines of a ``basestring``
 | |
|             or sequence"""
 | |
|             if isinstance(strs, str):
 | |
|                 for s in strs.splitlines():
 | |
|                     s = s.strip()
 | |
|                     # skip blank lines/comments
 | |
|                     if s and not s.startswith('#'):
 | |
|                         yield s
 | |
|             else:
 | |
|                 for ss in strs:
 | |
|                     for s in yield_lines(ss):
 | |
|                         yield s
 | |
| 
 | |
|         requires = None
 | |
| 
 | |
|         if path.endswith('.egg'):
 | |
|             if os.path.isdir(path):
 | |
|                 meta_path = os.path.join(path, 'EGG-INFO', 'PKG-INFO')
 | |
|                 self.metadata = Metadata(path=meta_path)
 | |
|                 try:
 | |
|                     req_path = os.path.join(path, 'EGG-INFO', 'requires.txt')
 | |
|                     with open(req_path, 'r') as fp:
 | |
|                         requires = fp.read()
 | |
|                 except IOError:
 | |
|                     requires = None
 | |
|             else:
 | |
|                 # FIXME handle the case where zipfile is not available
 | |
|                 zipf = zipimport.zipimporter(path)
 | |
|                 fileobj = io.StringIO(
 | |
|                     zipf.get_data('EGG-INFO/PKG-INFO').decode('utf8'))
 | |
|                 self.metadata = Metadata(fileobj=fileobj)
 | |
|                 try:
 | |
|                     requires = zipf.get_data('EGG-INFO/requires.txt')
 | |
|                 except IOError:
 | |
|                     requires = None
 | |
|             self.name = self.metadata['Name']
 | |
|             self.version = self.metadata['Version']
 | |
| 
 | |
|         elif path.endswith('.egg-info'):
 | |
|             if os.path.isdir(path):
 | |
|                 path = os.path.join(path, 'PKG-INFO')
 | |
|                 try:
 | |
|                     with open(os.path.join(path, 'requires.txt'), 'r') as fp:
 | |
|                         requires = fp.read()
 | |
|                 except IOError:
 | |
|                     requires = None
 | |
|             self.metadata = Metadata(path=path)
 | |
|             self.name = self.metadata['name']
 | |
|             self.version = self.metadata['Version']
 | |
| 
 | |
|         else:
 | |
|             raise ValueError('path must end with .egg-info or .egg, got %r' %
 | |
|                              path)
 | |
| 
 | |
|         if requires is not None:
 | |
|             if self.metadata['Metadata-Version'] == '1.1':
 | |
|                 # we can't have 1.1 metadata *and* Setuptools requires
 | |
|                 for field in ('Obsoletes', 'Requires', 'Provides'):
 | |
|                     del self.metadata[field]
 | |
| 
 | |
|         reqs = []
 | |
| 
 | |
|         if requires is not None:
 | |
|             for line in yield_lines(requires):
 | |
|                 if line.startswith('['):
 | |
|                     logger.warning(
 | |
|                         'extensions in requires.txt are not supported '
 | |
|                         '(used by %r %s)', self.name, self.version)
 | |
|                     break
 | |
|                 else:
 | |
|                     match = self._REQUIREMENT.match(line.strip())
 | |
|                     if not match:
 | |
|                         # this happens when we encounter extras; since they
 | |
|                         # are written at the end of the file we just exit
 | |
|                         break
 | |
|                     else:
 | |
|                         if match.group('extras'):
 | |
|                             msg = ('extra requirements are not supported '
 | |
|                                    '(used by %r %s)', self.name, self.version)
 | |
|                             logger.warning(msg, self.name)
 | |
|                         name = match.group('name')
 | |
|                         version = None
 | |
|                         if match.group('first'):
 | |
|                             version = match.group('first')
 | |
|                             if match.group('rest'):
 | |
|                                 version += match.group('rest')
 | |
|                             version = version.replace(' ', '')  # trim spaces
 | |
|                         if version is None:
 | |
|                             reqs.append(name)
 | |
|                         else:
 | |
|                             reqs.append('%s (%s)' % (name, version))
 | |
| 
 | |
|             if len(reqs) > 0:
 | |
|                 self.metadata['Requires-Dist'] += reqs
 | |
| 
 | |
|         if _cache_enabled:
 | |
|             _cache_path_egg[self.path] = self
 | |
| 
 | |
|     def __repr__(self):
 | |
|         return '<EggInfoDistribution %r %s at %r>' % (
 | |
|             self.name, self.version, self.path)
 | |
| 
 | |
|     def list_installed_files(self, local=False):
 | |
| 
 | |
|         def _md5(path):
 | |
|             with open(path, 'rb') as f:
 | |
|                 content = f.read()
 | |
|             return md5(content).hexdigest()
 | |
| 
 | |
|         def _size(path):
 | |
|             return os.stat(path).st_size
 | |
| 
 | |
|         path = self.path
 | |
|         if local:
 | |
|             path = path.replace('/', os.sep)
 | |
| 
 | |
|         # XXX What about scripts and data files ?
 | |
|         if os.path.isfile(path):
 | |
|             return [(path, _md5(path), _size(path))]
 | |
|         else:
 | |
|             files = []
 | |
|             for root, dir, files_ in os.walk(path):
 | |
|                 for item in files_:
 | |
|                     item = os.path.join(root, item)
 | |
|                     files.append((item, _md5(item), _size(item)))
 | |
|             return files
 | |
| 
 | |
|         return []
 | |
| 
 | |
|     def uses(self, path):
 | |
|         return False
 | |
| 
 | |
|     def __eq__(self, other):
 | |
|         return (isinstance(other, EggInfoDistribution) and
 | |
|                 self.path == other.path)
 | |
| 
 | |
|     # See http://docs.python.org/reference/datamodel#object.__hash__
 | |
|     __hash__ = object.__hash__
 | |
| 
 | |
| 
 | |
| def distinfo_dirname(name, version):
 | |
|     """
 | |
|     The *name* and *version* parameters are converted into their
 | |
|     filename-escaped form, i.e. any ``'-'`` characters are replaced
 | |
|     with ``'_'`` other than the one in ``'dist-info'`` and the one
 | |
|     separating the name from the version number.
 | |
| 
 | |
|     :parameter name: is converted to a standard distribution name by replacing
 | |
|                      any runs of non- alphanumeric characters with a single
 | |
|                      ``'-'``.
 | |
|     :type name: string
 | |
|     :parameter version: is converted to a standard version string. Spaces
 | |
|                         become dots, and all other non-alphanumeric characters
 | |
|                         (except dots) become dashes, with runs of multiple
 | |
|                         dashes condensed to a single dash.
 | |
|     :type version: string
 | |
|     :returns: directory name
 | |
|     :rtype: string"""
 | |
|     file_extension = '.dist-info'
 | |
|     name = name.replace('-', '_')
 | |
|     normalized_version = suggest_normalized_version(version)
 | |
|     # Because this is a lookup procedure, something will be returned even if
 | |
|     #   it is a version that cannot be normalized
 | |
|     if normalized_version is None:
 | |
|         # Unable to achieve normality?
 | |
|         normalized_version = version
 | |
|     return '-'.join([name, normalized_version]) + file_extension
 | |
| 
 | |
| 
 | |
| def get_distributions(use_egg_info=False, paths=sys.path):
 | |
|     """
 | |
|     Provides an iterator that looks for ``.dist-info`` directories in
 | |
|     ``sys.path`` and returns :class:`Distribution` instances for each one of
 | |
|     them. If the parameters *use_egg_info* is ``True``, then the ``.egg-info``
 | |
|     files and directores are iterated as well.
 | |
| 
 | |
|     :rtype: iterator of :class:`Distribution` and :class:`EggInfoDistribution`
 | |
|             instances
 | |
|     """
 | |
|     if not _cache_enabled:
 | |
|         for dist in _yield_distributions(True, use_egg_info, paths):
 | |
|             yield dist
 | |
|     else:
 | |
|         _generate_cache(use_egg_info, paths)
 | |
| 
 | |
|         for dist in _cache_path.values():
 | |
|             yield dist
 | |
| 
 | |
|         if use_egg_info:
 | |
|             for dist in _cache_path_egg.values():
 | |
|                 yield dist
 | |
| 
 | |
| 
 | |
| def get_distribution(name, use_egg_info=False, paths=None):
 | |
|     """
 | |
|     Scans all elements in ``sys.path`` and looks for all directories
 | |
|     ending with ``.dist-info``. Returns a :class:`Distribution`
 | |
|     corresponding to the ``.dist-info`` directory that contains the
 | |
|     ``METADATA`` that matches *name* for the *name* metadata field.
 | |
|     If no distribution exists with the given *name* and the parameter
 | |
|     *use_egg_info* is set to ``True``, then all files and directories ending
 | |
|     with ``.egg-info`` are scanned. A :class:`EggInfoDistribution` instance is
 | |
|     returned if one is found that has metadata that matches *name* for the
 | |
|     *name* metadata field.
 | |
| 
 | |
|     This function only returns the first result found, as no more than one
 | |
|     value is expected. If the directory is not found, ``None`` is returned.
 | |
| 
 | |
|     :rtype: :class:`Distribution` or :class:`EggInfoDistribution` or None
 | |
|     """
 | |
|     if paths == None:
 | |
|         paths = sys.path
 | |
| 
 | |
|     if not _cache_enabled:
 | |
|         for dist in _yield_distributions(True, use_egg_info, paths):
 | |
|             if dist.name == name:
 | |
|                 return dist
 | |
|     else:
 | |
|         _generate_cache(use_egg_info, paths)
 | |
| 
 | |
|         if name in _cache_name:
 | |
|             return _cache_name[name][0]
 | |
|         elif use_egg_info and name in _cache_name_egg:
 | |
|             return _cache_name_egg[name][0]
 | |
|         else:
 | |
|             return None
 | |
| 
 | |
| 
 | |
| def obsoletes_distribution(name, version=None, use_egg_info=False):
 | |
|     """
 | |
|     Iterates over all distributions to find which distributions obsolete
 | |
|     *name*.
 | |
| 
 | |
|     If a *version* is provided, it will be used to filter the results.
 | |
|     If the argument *use_egg_info* is set to ``True``, then ``.egg-info``
 | |
|     distributions will be considered as well.
 | |
| 
 | |
|     :type name: string
 | |
|     :type version: string
 | |
|     :parameter name:
 | |
|     """
 | |
|     for dist in get_distributions(use_egg_info):
 | |
|         obsoleted = (dist.metadata['Obsoletes-Dist'] +
 | |
|                      dist.metadata['Obsoletes'])
 | |
|         for obs in obsoleted:
 | |
|             o_components = obs.split(' ', 1)
 | |
|             if len(o_components) == 1 or version is None:
 | |
|                 if name == o_components[0]:
 | |
|                     yield dist
 | |
|                     break
 | |
|             else:
 | |
|                 try:
 | |
|                     predicate = VersionPredicate(obs)
 | |
|                 except ValueError:
 | |
|                     raise PackagingError(
 | |
|                         'distribution %r has ill-formed obsoletes field: '
 | |
|                         '%r' % (dist.name, obs))
 | |
|                 if name == o_components[0] and predicate.match(version):
 | |
|                     yield dist
 | |
|                     break
 | |
| 
 | |
| 
 | |
| def provides_distribution(name, version=None, use_egg_info=False):
 | |
|     """
 | |
|     Iterates over all distributions to find which distributions provide *name*.
 | |
|     If a *version* is provided, it will be used to filter the results. Scans
 | |
|     all elements in ``sys.path``  and looks for all directories ending with
 | |
|     ``.dist-info``. Returns a :class:`Distribution`  corresponding to the
 | |
|     ``.dist-info`` directory that contains a ``METADATA`` that matches *name*
 | |
|     for the name metadata. If the argument *use_egg_info* is set to ``True``,
 | |
|     then all files and directories ending with ``.egg-info`` are considered
 | |
|     as well and returns an :class:`EggInfoDistribution` instance.
 | |
| 
 | |
|     This function only returns the first result found, since no more than
 | |
|     one values are expected. If the directory is not found, returns ``None``.
 | |
| 
 | |
|     :parameter version: a version specifier that indicates the version
 | |
|                         required, conforming to the format in ``PEP-345``
 | |
| 
 | |
|     :type name: string
 | |
|     :type version: string
 | |
|     """
 | |
|     predicate = None
 | |
|     if not version is None:
 | |
|         try:
 | |
|             predicate = VersionPredicate(name + ' (' + version + ')')
 | |
|         except ValueError:
 | |
|             raise PackagingError('invalid name or version: %r, %r' %
 | |
|                                  (name, version))
 | |
| 
 | |
|     for dist in get_distributions(use_egg_info):
 | |
|         provided = dist.metadata['Provides-Dist'] + dist.metadata['Provides']
 | |
| 
 | |
|         for p in provided:
 | |
|             p_components = p.rsplit(' ', 1)
 | |
|             if len(p_components) == 1 or predicate is None:
 | |
|                 if name == p_components[0]:
 | |
|                     yield dist
 | |
|                     break
 | |
|             else:
 | |
|                 p_name, p_ver = p_components
 | |
|                 if len(p_ver) < 2 or p_ver[0] != '(' or p_ver[-1] != ')':
 | |
|                     raise PackagingError(
 | |
|                         'distribution %r has invalid Provides field: %r' %
 | |
|                         (dist.name, p))
 | |
|                 p_ver = p_ver[1:-1]  # trim off the parenthesis
 | |
|                 if p_name == name and predicate.match(p_ver):
 | |
|                     yield dist
 | |
|                     break
 | |
| 
 | |
| 
 | |
| def get_file_users(path):
 | |
|     """
 | |
|     Iterates over all distributions to find out which distributions use
 | |
|     *path*.
 | |
| 
 | |
|     :parameter path: can be a local absolute path or a relative
 | |
|                      ``'/'``-separated path.
 | |
|     :type path: string
 | |
|     :rtype: iterator of :class:`Distribution` instances
 | |
|     """
 | |
|     for dist in get_distributions():
 | |
|         if dist.uses(path):
 | |
|             yield dist
 | 
