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Diffstat (limited to '.emacs.d.back/.python-environments/default/lib/python3.7/site-packages/pip/_internal/cache.py')
| -rw-r--r-- | .emacs.d.back/.python-environments/default/lib/python3.7/site-packages/pip/_internal/cache.py | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/.emacs.d.back/.python-environments/default/lib/python3.7/site-packages/pip/_internal/cache.py b/.emacs.d.back/.python-environments/default/lib/python3.7/site-packages/pip/_internal/cache.py new file mode 100644 index 00000000..894624c1 --- /dev/null +++ b/.emacs.d.back/.python-environments/default/lib/python3.7/site-packages/pip/_internal/cache.py @@ -0,0 +1,224 @@ +"""Cache Management +""" + +import errno +import hashlib +import logging +import os + +from pip._vendor.packaging.utils import canonicalize_name + +from pip._internal.models.link import Link +from pip._internal.utils.compat import expanduser +from pip._internal.utils.misc import path_to_url +from pip._internal.utils.temp_dir import TempDirectory +from pip._internal.utils.typing import MYPY_CHECK_RUNNING +from pip._internal.wheel import InvalidWheelFilename, Wheel + +if MYPY_CHECK_RUNNING: + from typing import Optional, Set, List, Any + from pip._internal.index import FormatControl + +logger = logging.getLogger(__name__) + + +class Cache(object): + """An abstract class - provides cache directories for data from links + + + :param cache_dir: The root of the cache. + :param format_control: An object of FormatControl class to limit + binaries being read from the cache. + :param allowed_formats: which formats of files the cache should store. + ('binary' and 'source' are the only allowed values) + """ + + def __init__(self, cache_dir, format_control, allowed_formats): + # type: (str, FormatControl, Set[str]) -> None + super(Cache, self).__init__() + self.cache_dir = expanduser(cache_dir) if cache_dir else None + self.format_control = format_control + self.allowed_formats = allowed_formats + + _valid_formats = {"source", "binary"} + assert self.allowed_formats.union(_valid_formats) == _valid_formats + + def _get_cache_path_parts(self, link): + # type: (Link) -> List[str] + """Get parts of part that must be os.path.joined with cache_dir + """ + + # We want to generate an url to use as our cache key, we don't want to + # just re-use the URL because it might have other items in the fragment + # and we don't care about those. + key_parts = [link.url_without_fragment] + if link.hash_name is not None and link.hash is not None: + key_parts.append("=".join([link.hash_name, link.hash])) + key_url = "#".join(key_parts) + + # Encode our key url with sha224, we'll use this because it has similar + # security properties to sha256, but with a shorter total output (and + # thus less secure). However the differences don't make a lot of + # difference for our use case here. + hashed = hashlib.sha224(key_url.encode()).hexdigest() + + # We want to nest the directories some to prevent having a ton of top + # level directories where we might run out of sub directories on some + # FS. + parts = [hashed[:2], hashed[2:4], hashed[4:6], hashed[6:]] + + return parts + + def _get_candidates(self, link, package_name): + # type: (Link, Optional[str]) -> List[Any] + can_not_cache = ( + not self.cache_dir or + not package_name or + not link + ) + if can_not_cache: + return [] + + canonical_name = canonicalize_name(package_name) + formats = self.format_control.get_allowed_formats( + canonical_name + ) + if not self.allowed_formats.intersection(formats): + return [] + + root = self.get_path_for_link(link) + try: + return os.listdir(root) + except OSError as err: + if err.errno in {errno.ENOENT, errno.ENOTDIR}: + return [] + raise + + def get_path_for_link(self, link): + # type: (Link) -> str + """Return a directory to store cached items in for link. + """ + raise NotImplementedError() + + def get(self, link, package_name): + # type: (Link, Optional[str]) -> Link + """Returns a link to a cached item if it exists, otherwise returns the + passed link. + """ + raise NotImplementedError() + + def _link_for_candidate(self, link, candidate): + # type: (Link, str) -> Link + root = self.get_path_for_link(link) + path = os.path.join(root, candidate) + + return Link(path_to_url(path)) + + def cleanup(self): + # type: () -> None + pass + + +class SimpleWheelCache(Cache): + """A cache of wheels for future installs. + """ + + def __init__(self, cache_dir, format_control): + # type: (str, FormatControl) -> None + super(SimpleWheelCache, self).__init__( + cache_dir, format_control, {"binary"} + ) + + def get_path_for_link(self, link): + # type: (Link) -> str + """Return a directory to store cached wheels for link + + Because there are M wheels for any one sdist, we provide a directory + to cache them in, and then consult that directory when looking up + cache hits. + + We only insert things into the cache if they have plausible version + numbers, so that we don't contaminate the cache with things that were + not unique. E.g. ./package might have dozens of installs done for it + and build a version of 0.0...and if we built and cached a wheel, we'd + end up using the same wheel even if the source has been edited. + + :param link: The link of the sdist for which this will cache wheels. + """ + parts = self._get_cache_path_parts(link) + + # Store wheels within the root cache_dir + return os.path.join(self.cache_dir, "wheels", *parts) + + def get(self, link, package_name): + # type: (Link, Optional[str]) -> Link + candidates = [] + + for wheel_name in self._get_candidates(link, package_name): + try: + wheel = Wheel(wheel_name) + except InvalidWheelFilename: + continue + if not wheel.supported(): + # Built for a different python/arch/etc + continue + candidates.append((wheel.support_index_min(), wheel_name)) + + if not candidates: + return link + + return self._link_for_candidate(link, min(candidates)[1]) + + +class EphemWheelCache(SimpleWheelCache): + """A SimpleWheelCache that creates it's own temporary cache directory + """ + + def __init__(self, format_control): + # type: (FormatControl) -> None + self._temp_dir = TempDirectory(kind="ephem-wheel-cache") + self._temp_dir.create() + + super(EphemWheelCache, self).__init__( + self._temp_dir.path, format_control + ) + + def cleanup(self): + # type: () -> None + self._temp_dir.cleanup() + + +class WheelCache(Cache): + """Wraps EphemWheelCache and SimpleWheelCache into a single Cache + + This Cache allows for gracefully degradation, using the ephem wheel cache + when a certain link is not found in the simple wheel cache first. + """ + + def __init__(self, cache_dir, format_control): + # type: (str, FormatControl) -> None + super(WheelCache, self).__init__( + cache_dir, format_control, {'binary'} + ) + self._wheel_cache = SimpleWheelCache(cache_dir, format_control) + self._ephem_cache = EphemWheelCache(format_control) + + def get_path_for_link(self, link): + # type: (Link) -> str + return self._wheel_cache.get_path_for_link(link) + + def get_ephem_path_for_link(self, link): + # type: (Link) -> str + return self._ephem_cache.get_path_for_link(link) + + def get(self, link, package_name): + # type: (Link, Optional[str]) -> Link + retval = self._wheel_cache.get(link, package_name) + if retval is link: + retval = self._ephem_cache.get(link, package_name) + return retval + + def cleanup(self): + # type: () -> None + self._wheel_cache.cleanup() + self._ephem_cache.cleanup() |