FM / cachecontrol

/opt/imh/python3.13/lib/python3.13/site-packages/pip/_vendor/cachecontrol/

/opt/imh/python3.13/lib/python3.13/site-packages/pip/_vendor/cachecontrol

Name	Size	Mode	Actions
caches/	-	0755	rm
__pycache__/	-	0755	rm
adapter.py	6355	0644	edit dl rm
cache.py	1952	0644	edit dl rm
controller.py	18575	0644	edit dl rm
filewrapper.py	4292	0644	edit dl rm
heuristics.py	4834	0644	edit dl rm
py.typed	0	0644	edit dl rm
serialize.py	5163	0644	edit dl rm
wrapper.py	1417	0644	edit dl rm
_cmd.py	1737	0644	edit dl rm
__init__.py	676	0644	edit dl rm

Edit: /opt/imh/python3.13/lib/python3.13/site-packages/pip/_vendor/cachecontrol/controller.py (18575B)

# SPDX-FileCopyrightText: 2015 Eric Larson
#
# SPDX-License-Identifier: Apache-2.0

"""
The httplib2 algorithms ported for use with requests.
"""
from __future__ import annotations

import calendar
import logging
import re
import time
from email.utils import parsedate_tz
from typing import TYPE_CHECKING, Collection, Mapping

from pip._vendor.requests.structures import CaseInsensitiveDict

from pip._vendor.cachecontrol.cache import DictCache, SeparateBodyBaseCache
from pip._vendor.cachecontrol.serialize import Serializer

if TYPE_CHECKING:
    from typing import Literal

from pip._vendor.requests import PreparedRequest
    from pip._vendor.urllib3 import HTTPResponse

from pip._vendor.cachecontrol.cache import BaseCache

logger = logging.getLogger(__name__)

URI = re.compile(r"^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?")

PERMANENT_REDIRECT_STATUSES = (301, 308)

def parse_uri(uri: str) -> tuple[str, str, str, str, str]:
    """Parses a URI using the regex given in Appendix B of RFC 3986.

(scheme, authority, path, query, fragment) = parse_uri(uri)
    """
    match = URI.match(uri)
    assert match is not None
    groups = match.groups()
    return (groups[1], groups[3], groups[4], groups[6], groups[8])

class CacheController:
    """An interface to see if request should cached or not."""

def __init__(
        self,
        cache: BaseCache | None = None,
        cache_etags: bool = True,
        serializer: Serializer | None = None,
        status_codes: Collection[int] | None = None,
    ):
        self.cache = DictCache() if cache is None else cache
        self.cache_etags = cache_etags
        self.serializer = serializer or Serializer()
        self.cacheable_status_codes = status_codes or (200, 203, 300, 301, 308)

@classmethod
    def _urlnorm(cls, uri: str) -> str:
        """Normalize the URL to create a safe key for the cache"""
        (scheme, authority, path, query, fragment) = parse_uri(uri)
        if not scheme or not authority:
            raise Exception("Only absolute URIs are allowed. uri = %s" % uri)

scheme = scheme.lower()
        authority = authority.lower()

if not path:
            path = "/"

# Could do syntax based normalization of the URI before
        # computing the digest. See Section 6.2.2 of Std 66.
        request_uri = query and "?".join([path, query]) or path
        defrag_uri = scheme + "://" + authority + request_uri

return defrag_uri

@classmethod
    def cache_url(cls, uri: str) -> str:
        return cls._urlnorm(uri)

def parse_cache_control(self, headers: Mapping[str, str]) -> dict[str, int | None]:
        known_directives = {
            # https://tools.ietf.org/html/rfc7234#section-5.2
            "max-age": (int, True),
            "max-stale": (int, False),
            "min-fresh": (int, True),
            "no-cache": (None, False),
            "no-store": (None, False),
            "no-transform": (None, False),
            "only-if-cached": (None, False),
            "must-revalidate": (None, False),
            "public": (None, False),
            "private": (None, False),
            "proxy-revalidate": (None, False),
            "s-maxage": (int, True),
        }

cc_headers = headers.get("cache-control", headers.get("Cache-Control", ""))

retval: dict[str, int | None] = {}

for cc_directive in cc_headers.split(","):
            if not cc_directive.strip():
                continue

parts = cc_directive.split("=", 1)
            directive = parts[0].strip()

try:
                typ, required = known_directives[directive]
            except KeyError:
                logger.debug("Ignoring unknown cache-control directive: %s", directive)
                continue

if not typ or not required:
                retval[directive] = None
            if typ:
                try:
                    retval[directive] = typ(parts[1].strip())
                except IndexError:
                    if required:
                        logger.debug(
                            "Missing value for cache-control " "directive: %s",
                            directive,
                        )
                except ValueError:
                    logger.debug(
                        "Invalid value for cache-control directive " "%s, must be %s",
                        directive,
                        typ.__name__,
                    )

return retval

def _load_from_cache(self, request: PreparedRequest) -> HTTPResponse | None:
        """
        Load a cached response, or return None if it's not available.
        """
        # We do not support caching of partial content: so if the request contains a
        # Range header then we don't want to load anything from the cache.
        if "Range" in request.headers:
            return None

cache_url = request.url
        assert cache_url is not None
        cache_data = self.cache.get(cache_url)
        if cache_data is None:
            logger.debug("No cache entry available")
            return None

if isinstance(self.cache, SeparateBodyBaseCache):
            body_file = self.cache.get_body(cache_url)
        else:
            body_file = None

result = self.serializer.loads(request, cache_data, body_file)
        if result is None:
            logger.warning("Cache entry deserialization failed, entry ignored")
        return result

def cached_request(self, request: PreparedRequest) -> HTTPResponse | Literal[False]:
        """
        Return a cached response if it exists in the cache, otherwise
        return False.
        """
        assert request.url is not None
        cache_url = self.cache_url(request.url)
        logger.debug('Looking up "%s" in the cache', cache_url)
        cc = self.parse_cache_control(request.headers)

# Bail out if the request insists on fresh data
        if "no-cache" in cc:
            logger.debug('Request header has "no-cache", cache bypassed')
            return False

if "max-age" in cc and cc["max-age"] == 0:
            logger.debug('Request header has "max_age" as 0, cache bypassed')
            return False

# Check whether we can load the response from the cache:
        resp = self._load_from_cache(request)
        if not resp:
            return False

# If we have a cached permanent redirect, return it immediately. We
        # don't need to test our response for other headers b/c it is
        # intrinsically "cacheable" as it is Permanent.
        #
        # See:
        #   https://tools.ietf.org/html/rfc7231#section-6.4.2
        #
        # Client can try to refresh the value by repeating the request
        # with cache busting headers as usual (ie no-cache).
        if int(resp.status) in PERMANENT_REDIRECT_STATUSES:
            msg = (
                "Returning cached permanent redirect response "
                "(ignoring date and etag information)"
            )
            logger.debug(msg)
            return resp

headers: CaseInsensitiveDict[str] = CaseInsensitiveDict(resp.headers)
        if not headers or "date" not in headers:
            if "etag" not in headers:
                # Without date or etag, the cached response can never be used
                # and should be deleted.
                logger.debug("Purging cached response: no date or etag")
                self.cache.delete(cache_url)
            logger.debug("Ignoring cached response: no date")
            return False

now = time.time()
        time_tuple = parsedate_tz(headers["date"])
        assert time_tuple is not None
        date = calendar.timegm(time_tuple[:6])
        current_age = max(0, now - date)
        logger.debug("Current age based on date: %i", current_age)

# TODO: There is an assumption that the result will be a
        #       urllib3 response object. This may not be best since we
        #       could probably avoid instantiating or constructing the
        #       response until we know we need it.
        resp_cc = self.parse_cache_control(headers)

# determine freshness
        freshness_lifetime = 0

# Check the max-age pragma in the cache control header
        max_age = resp_cc.get("max-age")
        if max_age is not None:
            freshness_lifetime = max_age
            logger.debug("Freshness lifetime from max-age: %i", freshness_lifetime)

# If there isn't a max-age, check for an expires header
        elif "expires" in headers:
            expires = parsedate_tz(headers["expires"])
            if expires is not None:
                expire_time = calendar.timegm(expires[:6]) - date
                freshness_lifetime = max(0, expire_time)
                logger.debug("Freshness lifetime from expires: %i", freshness_lifetime)

# Determine if we are setting freshness limit in the
        # request. Note, this overrides what was in the response.
        max_age = cc.get("max-age")
        if max_age is not None:
            freshness_lifetime = max_age
            logger.debug(
                "Freshness lifetime from request max-age: %i", freshness_lifetime
            )

min_fresh = cc.get("min-fresh")
        if min_fresh is not None:
            # adjust our current age by our min fresh
            current_age += min_fresh
            logger.debug("Adjusted current age from min-fresh: %i", current_age)

# Return entry if it is fresh enough
        if freshness_lifetime > current_age:
            logger.debug('The response is "fresh", returning cached response')
            logger.debug("%i > %i", freshness_lifetime, current_age)
            return resp

# we're not fresh. If we don't have an Etag, clear it out
        if "etag" not in headers:
            logger.debug('The cached response is "stale" with no etag, purging')
            self.cache.delete(cache_url)

# return the original handler
        return False

def conditional_headers(self, request: PreparedRequest) -> dict[str, str]:
        resp = self._load_from_cache(request)
        new_headers = {}

if resp:
            headers: CaseInsensitiveDict[str] = CaseInsensitiveDict(resp.headers)

if "etag" in headers:
                new_headers["If-None-Match"] = headers["ETag"]

if "last-modified" in headers:
                new_headers["If-Modified-Since"] = headers["Last-Modified"]

return new_headers

def _cache_set(
        self,
        cache_url: str,
        request: PreparedRequest,
        response: HTTPResponse,
        body: bytes | None = None,
        expires_time: int | None = None,
    ) -> None:
        """
        Store the data in the cache.
        """
        if isinstance(self.cache, SeparateBodyBaseCache):
            # We pass in the body separately; just put a placeholder empty
            # string in the metadata.
            self.cache.set(
                cache_url,
                self.serializer.dumps(request, response, b""),
                expires=expires_time,
            )
            # body is None can happen when, for example, we're only updating
            # headers, as is the case in update_cached_response().
            if body is not None:
                self.cache.set_body(cache_url, body)
        else:
            self.cache.set(
                cache_url,
                self.serializer.dumps(request, response, body),
                expires=expires_time,
            )

def cache_response(
        self,
        request: PreparedRequest,
        response: HTTPResponse,
        body: bytes | None = None,
        status_codes: Collection[int] | None = None,
    ) -> None:
        """
        Algorithm for caching requests.

This assumes a requests Response object.
        """
        # From httplib2: Don't cache 206's since we aren't going to
        #                handle byte range requests
        cacheable_status_codes = status_codes or self.cacheable_status_codes
        if response.status not in cacheable_status_codes:
            logger.debug(
                "Status code %s not in %s", response.status, cacheable_status_codes
            )
            return

response_headers: CaseInsensitiveDict[str] = CaseInsensitiveDict(
            response.headers
        )

if "date" in response_headers:
            time_tuple = parsedate_tz(response_headers["date"])
            assert time_tuple is not None
            date = calendar.timegm(time_tuple[:6])
        else:
            date = 0

# If we've been given a body, our response has a Content-Length, that
        # Content-Length is valid then we can check to see if the body we've
        # been given matches the expected size, and if it doesn't we'll just
        # skip trying to cache it.
        if (
            body is not None
            and "content-length" in response_headers
            and response_headers["content-length"].isdigit()
            and int(response_headers["content-length"]) != len(body)
        ):
            return

cc_req = self.parse_cache_control(request.headers)
        cc = self.parse_cache_control(response_headers)

assert request.url is not None
        cache_url = self.cache_url(request.url)
        logger.debug('Updating cache with response from "%s"', cache_url)

# Delete it from the cache if we happen to have it stored there
        no_store = False
        if "no-store" in cc:
            no_store = True
            logger.debug('Response header has "no-store"')
        if "no-store" in cc_req:
            no_store = True
            logger.debug('Request header has "no-store"')
        if no_store and self.cache.get(cache_url):
            logger.debug('Purging existing cache entry to honor "no-store"')
            self.cache.delete(cache_url)
        if no_store:
            return

# https://tools.ietf.org/html/rfc7234#section-4.1:
        # A Vary header field-value of "*" always fails to match.
        # Storing such a response leads to a deserialization warning
        # during cache lookup and is not allowed to ever be served,
        # so storing it can be avoided.
        if "*" in response_headers.get("vary", ""):
            logger.debug('Response header has "Vary: *"')
            return

# If we've been given an etag, then keep the response
        if self.cache_etags and "etag" in response_headers:
            expires_time = 0
            if response_headers.get("expires"):
                expires = parsedate_tz(response_headers["expires"])
                if expires is not None:
                    expires_time = calendar.timegm(expires[:6]) - date

expires_time = max(expires_time, 14 * 86400)

logger.debug(f"etag object cached for {expires_time} seconds")
            logger.debug("Caching due to etag")
            self._cache_set(cache_url, request, response, body, expires_time)

# Add to the cache any permanent redirects. We do this before looking
        # that the Date headers.
        elif int(response.status) in PERMANENT_REDIRECT_STATUSES:
            logger.debug("Caching permanent redirect")
            self._cache_set(cache_url, request, response, b"")

# Add to the cache if the response headers demand it. If there
        # is no date header then we can't do anything about expiring
        # the cache.
        elif "date" in response_headers:
            time_tuple = parsedate_tz(response_headers["date"])
            assert time_tuple is not None
            date = calendar.timegm(time_tuple[:6])
            # cache when there is a max-age > 0
            max_age = cc.get("max-age")
            if max_age is not None and max_age > 0:
                logger.debug("Caching b/c date exists and max-age > 0")
                expires_time = max_age
                self._cache_set(
                    cache_url,
                    request,
                    response,
                    body,
                    expires_time,
                )

# If the request can expire, it means we should cache it
            # in the meantime.
            elif "expires" in response_headers:
                if response_headers["expires"]:
                    expires = parsedate_tz(response_headers["expires"])
                    if expires is not None:
                        expires_time = calendar.timegm(expires[:6]) - date
                    else:
                        expires_time = None

logger.debug(
                        "Caching b/c of expires header. expires in {} seconds".format(
                            expires_time
                        )
                    )
                    self._cache_set(
                        cache_url,
                        request,
                        response,
                        body,
                        expires_time,
                    )

def update_cached_response(
        self, request: PreparedRequest, response: HTTPResponse
    ) -> HTTPResponse:
        """On a 304 we will get a new set of headers that we want to
        update our cached value with, assuming we have one.

This should only ever be called when we've sent an ETag and
        gotten a 304 as the response.
        """
        assert request.url is not None
        cache_url = self.cache_url(request.url)
        cached_response = self._load_from_cache(request)

if not cached_response:
            # we didn't have a cached response
            return response

# Lets update our headers with the headers from the new request:
        # http://tools.ietf.org/html/draft-ietf-httpbis-p4-conditional-26#section-4.1
        #
        # The server isn't supposed to send headers that would make
        # the cached body invalid. But... just in case, we'll be sure
        # to strip out ones we know that might be problmatic due to
        # typical assumptions.
        excluded_headers = ["content-length"]

cached_response.headers.update(
            {
                k: v
                for k, v in response.headers.items()
                if k.lower() not in excluded_headers
            }
        )

# we want a 200 b/c we have content via the cache
        cached_response.status = 200

# update our cache
        self._cache_set(cache_url, request, cached_response)

return cached_response

cmd: