Upload New File

stbi/Lib/site-packages/pip/_vendor/cachecontrol/adapter.py

+import types
+import functools
+import zlib
+
+from pip._vendor.requests.adapters import HTTPAdapter
+
+from .controller import CacheController
+from .cache import DictCache
+from .filewrapper import CallbackFileWrapper
+
+
+class CacheControlAdapter(HTTPAdapter):
+    invalidating_methods = {"PUT", "DELETE"}
+
+    def __init__(
+        self,
+        cache=None,
+        cache_etags=True,
+        controller_class=None,
+        serializer=None,
+        heuristic=None,
+        cacheable_methods=None,
+        *args,
+        **kw
+    ):
+        super(CacheControlAdapter, self).__init__(*args, **kw)
+        self.cache = DictCache() if cache is None else cache
+        self.heuristic = heuristic
+        self.cacheable_methods = cacheable_methods or ("GET",)
+
+        controller_factory = controller_class or CacheController
+        self.controller = controller_factory(
+            self.cache, cache_etags=cache_etags, serializer=serializer
+        )
+
+    def send(self, request, cacheable_methods=None, **kw):
+        """
+        Send a request. Use the request information to see if it
+        exists in the cache and cache the response if we need to and can.
+        """
+        cacheable = cacheable_methods or self.cacheable_methods
+        if request.method in cacheable:
+            try:
+                cached_response = self.controller.cached_request(request)
+            except zlib.error:
+                cached_response = None
+            if cached_response:
+                return self.build_response(request, cached_response, from_cache=True)
+
+            # check for etags and add headers if appropriate
+            request.headers.update(self.controller.conditional_headers(request))
+
+        resp = super(CacheControlAdapter, self).send(request, **kw)
+
+        return resp
+
+    def build_response(
+        self, request, response, from_cache=False, cacheable_methods=None
+    ):
+        """
+        Build a response by making a request or using the cache.
+
+        This will end up calling send and returning a potentially
+        cached response
+        """
+        cacheable = cacheable_methods or self.cacheable_methods
+        if not from_cache and request.method in cacheable:
+            # Check for any heuristics that might update headers
+            # before trying to cache.
+            if self.heuristic:
+                response = self.heuristic.apply(response)
+
+            # apply any expiration heuristics
+            if response.status == 304:
+                # We must have sent an ETag request. This could mean
+                # that we've been expired already or that we simply
+                # have an etag. In either case, we want to try and
+                # update the cache if that is the case.
+                cached_response = self.controller.update_cached_response(
+                    request, response
+                )
+
+                if cached_response is not response:
+                    from_cache = True
+
+                # We are done with the server response, read a
+                # possible response body (compliant servers will
+                # not return one, but we cannot be 100% sure) and
+                # release the connection back to the pool.
+                response.read(decode_content=False)
+                response.release_conn()
+
+                response = cached_response
+
+            # We always cache the 301 responses
+            elif response.status == 301:
+                self.controller.cache_response(request, response)
+            else:
+                # Wrap the response file with a wrapper that will cache the
+                #   response when the stream has been consumed.
+                response._fp = CallbackFileWrapper(
+                    response._fp,
+                    functools.partial(
+                        self.controller.cache_response, request, response
+                    ),
+                )
+                if response.chunked:
+                    super_update_chunk_length = response._update_chunk_length
+
+                    def _update_chunk_length(self):
+                        super_update_chunk_length()
+                        if self.chunk_left == 0:
+                            self._fp._close()
+
+                    response._update_chunk_length = types.MethodType(
+                        _update_chunk_length, response
+                    )
+
+        resp = super(CacheControlAdapter, self).build_response(request, response)
+
+        # See if we should invalidate the cache.
+        if request.method in self.invalidating_methods and resp.ok:
+            cache_url = self.controller.cache_url(request.url)
+            self.cache.delete(cache_url)
+
+        # Give the request a from_cache attr to let people use it
+        resp.from_cache = from_cache
+
+        return resp
+
+    def close(self):
+        self.cache.close()
+        super(CacheControlAdapter, self).close()