AlkantarClanX12
Current Path : /lib/python3.6/site-packages/pip/_vendor/cachecontrol/ |
Current File : //lib/python3.6/site-packages/pip/_vendor/cachecontrol/serialize.py |
import base64 import io import json import zlib from pip._vendor.requests.structures import CaseInsensitiveDict from .compat import HTTPResponse, pickle, text_type def _b64_encode_bytes(b): return base64.b64encode(b).decode("ascii") def _b64_encode_str(s): return _b64_encode_bytes(s.encode("utf8")) def _b64_encode(s): if isinstance(s, text_type): return _b64_encode_str(s) return _b64_encode_bytes(s) def _b64_decode_bytes(b): return base64.b64decode(b.encode("ascii")) def _b64_decode_str(s): return _b64_decode_bytes(s).decode("utf8") class Serializer(object): def dumps(self, request, response, body=None): response_headers = CaseInsensitiveDict(response.headers) if body is None: body = response.read(decode_content=False) # NOTE: 99% sure this is dead code. I'm only leaving it # here b/c I don't have a test yet to prove # it. Basically, before using # `cachecontrol.filewrapper.CallbackFileWrapper`, # this made an effort to reset the file handle. The # `CallbackFileWrapper` short circuits this code by # setting the body as the content is consumed, the # result being a `body` argument is *always* passed # into cache_response, and in turn, # `Serializer.dump`. response._fp = io.BytesIO(body) data = { "response": { "body": _b64_encode_bytes(body), "headers": dict( (_b64_encode(k), _b64_encode(v)) for k, v in response.headers.items() ), "status": response.status, "version": response.version, "reason": _b64_encode_str(response.reason), "strict": response.strict, "decode_content": response.decode_content, }, } # Construct our vary headers data["vary"] = {} if "vary" in response_headers: varied_headers = response_headers['vary'].split(',') for header in varied_headers: header = header.strip() data["vary"][header] = request.headers.get(header, None) # Encode our Vary headers to ensure they can be serialized as JSON data["vary"] = dict( (_b64_encode(k), _b64_encode(v) if v is not None else v) for k, v in data["vary"].items() ) return b",".join([ b"cc=2", zlib.compress( json.dumps( data, separators=(",", ":"), sort_keys=True, ).encode("utf8"), ), ]) def loads(self, request, data): # Short circuit if we've been given an empty set of data if not data: return # Determine what version of the serializer the data was serialized # with try: ver, data = data.split(b",", 1) except ValueError: ver = b"cc=0" # Make sure that our "ver" is actually a version and isn't a false # positive from a , being in the data stream. if ver[:3] != b"cc=": data = ver + data ver = b"cc=0" # Get the version number out of the cc=N ver = ver.split(b"=", 1)[-1].decode("ascii") # Dispatch to the actual load method for the given version try: return getattr(self, "_loads_v{0}".format(ver))(request, data) except AttributeError: # This is a version we don't have a loads function for, so we'll # just treat it as a miss and return None return def prepare_response(self, request, cached): """Verify our vary headers match and construct a real urllib3 HTTPResponse object. """ # Special case the '*' Vary value as it means we cannot actually # determine if the cached response is suitable for this request. if "*" in cached.get("vary", {}): return # Ensure that the Vary headers for the cached response match our # request for header, value in cached.get("vary", {}).items(): if request.headers.get(header, None) != value: return body_raw = cached["response"].pop("body") headers = CaseInsensitiveDict(data=cached['response']['headers']) if headers.get('transfer-encoding', '') == 'chunked': headers.pop('transfer-encoding') cached['response']['headers'] = headers try: body = io.BytesIO(body_raw) except TypeError: # This can happen if cachecontrol serialized to v1 format (pickle) # using Python 2. A Python 2 str(byte string) will be unpickled as # a Python 3 str (unicode string), which will cause the above to # fail with: # # TypeError: 'str' does not support the buffer interface body = io.BytesIO(body_raw.encode('utf8')) return HTTPResponse( body=body, preload_content=False, **cached["response"] ) def _loads_v0(self, request, data): # The original legacy cache data. This doesn't contain enough # information to construct everything we need, so we'll treat this as # a miss. return def _loads_v1(self, request, data): try: cached = pickle.loads(data) except ValueError: return return self.prepare_response(request, cached) def _loads_v2(self, request, data): try: cached = json.loads(zlib.decompress(data).decode("utf8")) except ValueError: return # We need to decode the items that we've base64 encoded cached["response"]["body"] = _b64_decode_bytes( cached["response"]["body"] ) cached["response"]["headers"] = dict( (_b64_decode_str(k), _b64_decode_str(v)) for k, v in cached["response"]["headers"].items() ) cached["response"]["reason"] = _b64_decode_str( cached["response"]["reason"], ) cached["vary"] = dict( (_b64_decode_str(k), _b64_decode_str(v) if v is not None else v) for k, v in cached["vary"].items() ) return self.prepare_response(request, cached)