1328 lines
42 KiB
Python
1328 lines
42 KiB
Python
import base64
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import email.utils
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import re
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import typing
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import typing as t
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import warnings
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from datetime import date
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from datetime import datetime
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from datetime import time
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from datetime import timedelta
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from datetime import timezone
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from enum import Enum
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from hashlib import sha1
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from time import mktime
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from time import struct_time
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from urllib.parse import unquote_to_bytes as _unquote
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from urllib.request import parse_http_list as _parse_list_header
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from ._internal import _cookie_quote
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from ._internal import _dt_as_utc
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from ._internal import _make_cookie_domain
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from ._internal import _to_bytes
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from ._internal import _to_str
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from ._internal import _wsgi_decoding_dance
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if t.TYPE_CHECKING:
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from _typeshed.wsgi import WSGIEnvironment
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# for explanation of "media-range", etc. see Sections 5.3.{1,2} of RFC 7231
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_accept_re = re.compile(
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r"""
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( # media-range capturing-parenthesis
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[^\s;,]+ # type/subtype
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(?:[ \t]*;[ \t]* # ";"
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(?: # parameter non-capturing-parenthesis
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[^\s;,q][^\s;,]* # token that doesn't start with "q"
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| # or
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q[^\s;,=][^\s;,]* # token that is more than just "q"
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)
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)* # zero or more parameters
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) # end of media-range
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(?:[ \t]*;[ \t]*q= # weight is a "q" parameter
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(\d*(?:\.\d+)?) # qvalue capturing-parentheses
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[^,]* # "extension" accept params: who cares?
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)? # accept params are optional
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""",
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re.VERBOSE,
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)
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_token_chars = frozenset(
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"!#$%&'*+-.0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ^_`abcdefghijklmnopqrstuvwxyz|~"
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)
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_etag_re = re.compile(r'([Ww]/)?(?:"(.*?)"|(.*?))(?:\s*,\s*|$)')
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_option_header_piece_re = re.compile(
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r"""
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;\s*,?\s* # newlines were replaced with commas
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(?P<key>
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"[^"\\]*(?:\\.[^"\\]*)*" # quoted string
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[^\s;,=*]+ # token
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)
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(?:\*(?P<count>\d+))? # *1, optional continuation index
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\s*
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(?: # optionally followed by =value
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(?: # equals sign, possibly with encoding
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\*\s*=\s* # * indicates extended notation
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(?: # optional encoding
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(?P<encoding>[^\s]+?)
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'(?P<language>[^\s]*?)'
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)?
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=\s* # basic notation
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)
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(?P<value>
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"[^"\\]*(?:\\.[^"\\]*)*" # quoted string
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[^;,]+ # token
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)?
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)?
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\s*
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""",
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flags=re.VERBOSE,
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)
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_option_header_start_mime_type = re.compile(r",\s*([^;,\s]+)([;,]\s*.+)?")
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_entity_headers = frozenset(
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[
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"allow",
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"content-encoding",
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"content-language",
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"content-length",
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"content-location",
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"content-md5",
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"content-range",
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"content-type",
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"expires",
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"last-modified",
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]
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)
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_hop_by_hop_headers = frozenset(
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[
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"connection",
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"keep-alive",
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"proxy-authenticate",
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"proxy-authorization",
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"te",
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"trailer",
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"transfer-encoding",
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"upgrade",
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]
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)
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HTTP_STATUS_CODES = {
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100: "Continue",
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101: "Switching Protocols",
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102: "Processing",
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103: "Early Hints", # see RFC 8297
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200: "OK",
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201: "Created",
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202: "Accepted",
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203: "Non Authoritative Information",
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204: "No Content",
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205: "Reset Content",
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206: "Partial Content",
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207: "Multi Status",
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208: "Already Reported", # see RFC 5842
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226: "IM Used", # see RFC 3229
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300: "Multiple Choices",
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301: "Moved Permanently",
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302: "Found",
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303: "See Other",
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304: "Not Modified",
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305: "Use Proxy",
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306: "Switch Proxy", # unused
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307: "Temporary Redirect",
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308: "Permanent Redirect",
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400: "Bad Request",
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401: "Unauthorized",
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402: "Payment Required", # unused
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403: "Forbidden",
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404: "Not Found",
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405: "Method Not Allowed",
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406: "Not Acceptable",
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407: "Proxy Authentication Required",
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408: "Request Timeout",
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409: "Conflict",
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410: "Gone",
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411: "Length Required",
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412: "Precondition Failed",
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413: "Request Entity Too Large",
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414: "Request URI Too Long",
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415: "Unsupported Media Type",
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416: "Requested Range Not Satisfiable",
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417: "Expectation Failed",
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418: "I'm a teapot", # see RFC 2324
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421: "Misdirected Request", # see RFC 7540
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422: "Unprocessable Entity",
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423: "Locked",
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424: "Failed Dependency",
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425: "Too Early", # see RFC 8470
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426: "Upgrade Required",
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428: "Precondition Required", # see RFC 6585
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429: "Too Many Requests",
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431: "Request Header Fields Too Large",
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449: "Retry With", # proprietary MS extension
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451: "Unavailable For Legal Reasons",
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500: "Internal Server Error",
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501: "Not Implemented",
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502: "Bad Gateway",
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503: "Service Unavailable",
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504: "Gateway Timeout",
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505: "HTTP Version Not Supported",
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506: "Variant Also Negotiates", # see RFC 2295
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507: "Insufficient Storage",
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508: "Loop Detected", # see RFC 5842
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510: "Not Extended",
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511: "Network Authentication Failed",
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}
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class COEP(Enum):
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"""Cross Origin Embedder Policies"""
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UNSAFE_NONE = "unsafe-none"
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REQUIRE_CORP = "require-corp"
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class COOP(Enum):
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"""Cross Origin Opener Policies"""
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UNSAFE_NONE = "unsafe-none"
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SAME_ORIGIN_ALLOW_POPUPS = "same-origin-allow-popups"
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SAME_ORIGIN = "same-origin"
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def _is_extended_parameter(key: str) -> bool:
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"""Per RFC 5987/8187, "extended" values may *not* be quoted.
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This is in keeping with browser implementations. So we test
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using this function to see if the key indicates this parameter
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follows the `ext-parameter` syntax (using a trailing '*').
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"""
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return key.strip().endswith("*")
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def quote_header_value(
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value: t.Union[str, int], extra_chars: str = "", allow_token: bool = True
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) -> str:
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"""Quote a header value if necessary.
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.. versionadded:: 0.5
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:param value: the value to quote.
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:param extra_chars: a list of extra characters to skip quoting.
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:param allow_token: if this is enabled token values are returned
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unchanged.
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"""
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if isinstance(value, bytes):
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value = value.decode("latin1")
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value = str(value)
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if allow_token:
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token_chars = _token_chars | set(extra_chars)
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if set(value).issubset(token_chars):
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return value
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value = value.replace("\\", "\\\\").replace('"', '\\"')
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return f'"{value}"'
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def unquote_header_value(value: str, is_filename: bool = False) -> str:
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r"""Unquotes a header value. (Reversal of :func:`quote_header_value`).
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This does not use the real unquoting but what browsers are actually
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using for quoting.
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.. versionadded:: 0.5
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:param value: the header value to unquote.
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:param is_filename: The value represents a filename or path.
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"""
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if value and value[0] == value[-1] == '"':
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# this is not the real unquoting, but fixing this so that the
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# RFC is met will result in bugs with internet explorer and
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# probably some other browsers as well. IE for example is
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# uploading files with "C:\foo\bar.txt" as filename
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value = value[1:-1]
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# if this is a filename and the starting characters look like
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# a UNC path, then just return the value without quotes. Using the
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# replace sequence below on a UNC path has the effect of turning
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# the leading double slash into a single slash and then
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# _fix_ie_filename() doesn't work correctly. See #458.
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if not is_filename or value[:2] != "\\\\":
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return value.replace("\\\\", "\\").replace('\\"', '"')
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return value
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def dump_options_header(
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header: t.Optional[str], options: t.Mapping[str, t.Optional[t.Union[str, int]]]
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) -> str:
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"""The reverse function to :func:`parse_options_header`.
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:param header: the header to dump
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:param options: a dict of options to append.
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"""
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segments = []
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if header is not None:
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segments.append(header)
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for key, value in options.items():
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if value is None:
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segments.append(key)
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elif _is_extended_parameter(key):
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segments.append(f"{key}={value}")
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else:
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segments.append(f"{key}={quote_header_value(value)}")
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return "; ".join(segments)
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def dump_header(
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iterable: t.Union[t.Dict[str, t.Union[str, int]], t.Iterable[str]],
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allow_token: bool = True,
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) -> str:
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"""Dump an HTTP header again. This is the reversal of
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:func:`parse_list_header`, :func:`parse_set_header` and
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:func:`parse_dict_header`. This also quotes strings that include an
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equals sign unless you pass it as dict of key, value pairs.
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>>> dump_header({'foo': 'bar baz'})
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'foo="bar baz"'
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>>> dump_header(('foo', 'bar baz'))
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'foo, "bar baz"'
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:param iterable: the iterable or dict of values to quote.
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:param allow_token: if set to `False` tokens as values are disallowed.
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See :func:`quote_header_value` for more details.
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"""
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if isinstance(iterable, dict):
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items = []
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for key, value in iterable.items():
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if value is None:
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items.append(key)
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elif _is_extended_parameter(key):
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items.append(f"{key}={value}")
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else:
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items.append(
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f"{key}={quote_header_value(value, allow_token=allow_token)}"
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)
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else:
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items = [quote_header_value(x, allow_token=allow_token) for x in iterable]
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return ", ".join(items)
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def dump_csp_header(header: "ds.ContentSecurityPolicy") -> str:
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"""Dump a Content Security Policy header.
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These are structured into policies such as "default-src 'self';
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script-src 'self'".
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.. versionadded:: 1.0.0
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Support for Content Security Policy headers was added.
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"""
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return "; ".join(f"{key} {value}" for key, value in header.items())
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def parse_list_header(value: str) -> t.List[str]:
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"""Parse lists as described by RFC 2068 Section 2.
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In particular, parse comma-separated lists where the elements of
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the list may include quoted-strings. A quoted-string could
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contain a comma. A non-quoted string could have quotes in the
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middle. Quotes are removed automatically after parsing.
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It basically works like :func:`parse_set_header` just that items
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may appear multiple times and case sensitivity is preserved.
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The return value is a standard :class:`list`:
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>>> parse_list_header('token, "quoted value"')
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['token', 'quoted value']
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To create a header from the :class:`list` again, use the
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:func:`dump_header` function.
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:param value: a string with a list header.
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:return: :class:`list`
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"""
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result = []
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for item in _parse_list_header(value):
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if item[:1] == item[-1:] == '"':
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item = unquote_header_value(item[1:-1])
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result.append(item)
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return result
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def parse_dict_header(value: str, cls: t.Type[dict] = dict) -> t.Dict[str, str]:
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"""Parse lists of key, value pairs as described by RFC 2068 Section 2 and
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convert them into a python dict (or any other mapping object created from
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the type with a dict like interface provided by the `cls` argument):
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>>> d = parse_dict_header('foo="is a fish", bar="as well"')
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>>> type(d) is dict
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True
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>>> sorted(d.items())
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[('bar', 'as well'), ('foo', 'is a fish')]
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If there is no value for a key it will be `None`:
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>>> parse_dict_header('key_without_value')
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{'key_without_value': None}
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To create a header from the :class:`dict` again, use the
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:func:`dump_header` function.
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.. versionchanged:: 0.9
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Added support for `cls` argument.
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:param value: a string with a dict header.
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:param cls: callable to use for storage of parsed results.
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:return: an instance of `cls`
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"""
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result = cls()
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if isinstance(value, bytes):
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value = value.decode("latin1")
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for item in _parse_list_header(value):
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if "=" not in item:
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result[item] = None
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continue
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name, value = item.split("=", 1)
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if value[:1] == value[-1:] == '"':
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value = unquote_header_value(value[1:-1])
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result[name] = value
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return result
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def parse_options_header(value: t.Optional[str]) -> t.Tuple[str, t.Dict[str, str]]:
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"""Parse a ``Content-Type``-like header into a tuple with the
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value and any options:
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>>> parse_options_header('text/html; charset=utf8')
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('text/html', {'charset': 'utf8'})
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This should is not for ``Cache-Control``-like headers, which use a
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different format. For those, use :func:`parse_dict_header`.
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:param value: The header value to parse.
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.. versionchanged:: 2.2
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Option names are always converted to lowercase.
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.. versionchanged:: 2.1
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The ``multiple`` parameter is deprecated and will be removed in
|
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Werkzeug 2.2.
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.. versionchanged:: 0.15
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:rfc:`2231` parameter continuations are handled.
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.. versionadded:: 0.5
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"""
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if not value:
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return "", {}
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result: t.List[t.Any] = []
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value = "," + value.replace("\n", ",")
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while value:
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match = _option_header_start_mime_type.match(value)
|
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if not match:
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break
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result.append(match.group(1)) # mimetype
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options: t.Dict[str, str] = {}
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# Parse options
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rest = match.group(2)
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encoding: t.Optional[str]
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continued_encoding: t.Optional[str] = None
|
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while rest:
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optmatch = _option_header_piece_re.match(rest)
|
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if not optmatch:
|
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break
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option, count, encoding, language, option_value = optmatch.groups()
|
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# Continuations don't have to supply the encoding after the
|
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# first line. If we're in a continuation, track the current
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# encoding to use for subsequent lines. Reset it when the
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# continuation ends.
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if not count:
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continued_encoding = None
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else:
|
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if not encoding:
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encoding = continued_encoding
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continued_encoding = encoding
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option = unquote_header_value(option).lower()
|
|
|
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if option_value is not None:
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option_value = unquote_header_value(option_value, option == "filename")
|
|
|
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if encoding is not None:
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option_value = _unquote(option_value).decode(encoding)
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|
|
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if count:
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# Continuations append to the existing value. For
|
|
# simplicity, this ignores the possibility of
|
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# out-of-order indices, which shouldn't happen anyway.
|
|
if option_value is not None:
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options[option] = options.get(option, "") + option_value
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else:
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options[option] = option_value # type: ignore[assignment]
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|
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rest = rest[optmatch.end() :]
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result.append(options)
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return tuple(result) # type: ignore[return-value]
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|
|
return tuple(result) if result else ("", {}) # type: ignore[return-value]
|
|
|
|
|
|
_TAnyAccept = t.TypeVar("_TAnyAccept", bound="ds.Accept")
|
|
|
|
|
|
@typing.overload
|
|
def parse_accept_header(value: t.Optional[str]) -> "ds.Accept":
|
|
...
|
|
|
|
|
|
@typing.overload
|
|
def parse_accept_header(
|
|
value: t.Optional[str], cls: t.Type[_TAnyAccept]
|
|
) -> _TAnyAccept:
|
|
...
|
|
|
|
|
|
def parse_accept_header(
|
|
value: t.Optional[str], cls: t.Optional[t.Type[_TAnyAccept]] = None
|
|
) -> _TAnyAccept:
|
|
"""Parses an HTTP Accept-* header. This does not implement a complete
|
|
valid algorithm but one that supports at least value and quality
|
|
extraction.
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|
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|
Returns a new :class:`Accept` object (basically a list of ``(value, quality)``
|
|
tuples sorted by the quality with some additional accessor methods).
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|
|
|
The second parameter can be a subclass of :class:`Accept` that is created
|
|
with the parsed values and returned.
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|
|
:param value: the accept header string to be parsed.
|
|
:param cls: the wrapper class for the return value (can be
|
|
:class:`Accept` or a subclass thereof)
|
|
:return: an instance of `cls`.
|
|
"""
|
|
if cls is None:
|
|
cls = t.cast(t.Type[_TAnyAccept], ds.Accept)
|
|
|
|
if not value:
|
|
return cls(None)
|
|
|
|
result = []
|
|
for match in _accept_re.finditer(value):
|
|
quality_match = match.group(2)
|
|
if not quality_match:
|
|
quality: float = 1
|
|
else:
|
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quality = max(min(float(quality_match), 1), 0)
|
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result.append((match.group(1), quality))
|
|
return cls(result)
|
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|
|
|
|
_TAnyCC = t.TypeVar("_TAnyCC", bound="ds._CacheControl")
|
|
_t_cc_update = t.Optional[t.Callable[[_TAnyCC], None]]
|
|
|
|
|
|
@typing.overload
|
|
def parse_cache_control_header(
|
|
value: t.Optional[str], on_update: _t_cc_update, cls: None = None
|
|
) -> "ds.RequestCacheControl":
|
|
...
|
|
|
|
|
|
@typing.overload
|
|
def parse_cache_control_header(
|
|
value: t.Optional[str], on_update: _t_cc_update, cls: t.Type[_TAnyCC]
|
|
) -> _TAnyCC:
|
|
...
|
|
|
|
|
|
def parse_cache_control_header(
|
|
value: t.Optional[str],
|
|
on_update: _t_cc_update = None,
|
|
cls: t.Optional[t.Type[_TAnyCC]] = None,
|
|
) -> _TAnyCC:
|
|
"""Parse a cache control header. The RFC differs between response and
|
|
request cache control, this method does not. It's your responsibility
|
|
to not use the wrong control statements.
|
|
|
|
.. versionadded:: 0.5
|
|
The `cls` was added. If not specified an immutable
|
|
:class:`~werkzeug.datastructures.RequestCacheControl` is returned.
|
|
|
|
:param value: a cache control header to be parsed.
|
|
:param on_update: an optional callable that is called every time a value
|
|
on the :class:`~werkzeug.datastructures.CacheControl`
|
|
object is changed.
|
|
:param cls: the class for the returned object. By default
|
|
:class:`~werkzeug.datastructures.RequestCacheControl` is used.
|
|
:return: a `cls` object.
|
|
"""
|
|
if cls is None:
|
|
cls = t.cast(t.Type[_TAnyCC], ds.RequestCacheControl)
|
|
|
|
if not value:
|
|
return cls((), on_update)
|
|
|
|
return cls(parse_dict_header(value), on_update)
|
|
|
|
|
|
_TAnyCSP = t.TypeVar("_TAnyCSP", bound="ds.ContentSecurityPolicy")
|
|
_t_csp_update = t.Optional[t.Callable[[_TAnyCSP], None]]
|
|
|
|
|
|
@typing.overload
|
|
def parse_csp_header(
|
|
value: t.Optional[str], on_update: _t_csp_update, cls: None = None
|
|
) -> "ds.ContentSecurityPolicy":
|
|
...
|
|
|
|
|
|
@typing.overload
|
|
def parse_csp_header(
|
|
value: t.Optional[str], on_update: _t_csp_update, cls: t.Type[_TAnyCSP]
|
|
) -> _TAnyCSP:
|
|
...
|
|
|
|
|
|
def parse_csp_header(
|
|
value: t.Optional[str],
|
|
on_update: _t_csp_update = None,
|
|
cls: t.Optional[t.Type[_TAnyCSP]] = None,
|
|
) -> _TAnyCSP:
|
|
"""Parse a Content Security Policy header.
|
|
|
|
.. versionadded:: 1.0.0
|
|
Support for Content Security Policy headers was added.
|
|
|
|
:param value: a csp header to be parsed.
|
|
:param on_update: an optional callable that is called every time a value
|
|
on the object is changed.
|
|
:param cls: the class for the returned object. By default
|
|
:class:`~werkzeug.datastructures.ContentSecurityPolicy` is used.
|
|
:return: a `cls` object.
|
|
"""
|
|
if cls is None:
|
|
cls = t.cast(t.Type[_TAnyCSP], ds.ContentSecurityPolicy)
|
|
|
|
if value is None:
|
|
return cls((), on_update)
|
|
|
|
items = []
|
|
|
|
for policy in value.split(";"):
|
|
policy = policy.strip()
|
|
|
|
# Ignore badly formatted policies (no space)
|
|
if " " in policy:
|
|
directive, value = policy.strip().split(" ", 1)
|
|
items.append((directive.strip(), value.strip()))
|
|
|
|
return cls(items, on_update)
|
|
|
|
|
|
def parse_set_header(
|
|
value: t.Optional[str],
|
|
on_update: t.Optional[t.Callable[["ds.HeaderSet"], None]] = None,
|
|
) -> "ds.HeaderSet":
|
|
"""Parse a set-like header and return a
|
|
:class:`~werkzeug.datastructures.HeaderSet` object:
|
|
|
|
>>> hs = parse_set_header('token, "quoted value"')
|
|
|
|
The return value is an object that treats the items case-insensitively
|
|
and keeps the order of the items:
|
|
|
|
>>> 'TOKEN' in hs
|
|
True
|
|
>>> hs.index('quoted value')
|
|
1
|
|
>>> hs
|
|
HeaderSet(['token', 'quoted value'])
|
|
|
|
To create a header from the :class:`HeaderSet` again, use the
|
|
:func:`dump_header` function.
|
|
|
|
:param value: a set header to be parsed.
|
|
:param on_update: an optional callable that is called every time a
|
|
value on the :class:`~werkzeug.datastructures.HeaderSet`
|
|
object is changed.
|
|
:return: a :class:`~werkzeug.datastructures.HeaderSet`
|
|
"""
|
|
if not value:
|
|
return ds.HeaderSet(None, on_update)
|
|
return ds.HeaderSet(parse_list_header(value), on_update)
|
|
|
|
|
|
def parse_authorization_header(
|
|
value: t.Optional[str],
|
|
) -> t.Optional["ds.Authorization"]:
|
|
"""Parse an HTTP basic/digest authorization header transmitted by the web
|
|
browser. The return value is either `None` if the header was invalid or
|
|
not given, otherwise an :class:`~werkzeug.datastructures.Authorization`
|
|
object.
|
|
|
|
:param value: the authorization header to parse.
|
|
:return: a :class:`~werkzeug.datastructures.Authorization` object or `None`.
|
|
"""
|
|
if not value:
|
|
return None
|
|
value = _wsgi_decoding_dance(value)
|
|
try:
|
|
auth_type, auth_info = value.split(None, 1)
|
|
auth_type = auth_type.lower()
|
|
except ValueError:
|
|
return None
|
|
if auth_type == "basic":
|
|
try:
|
|
username, password = base64.b64decode(auth_info).split(b":", 1)
|
|
except Exception:
|
|
return None
|
|
try:
|
|
return ds.Authorization(
|
|
"basic",
|
|
{
|
|
"username": _to_str(username, "utf-8"),
|
|
"password": _to_str(password, "utf-8"),
|
|
},
|
|
)
|
|
except UnicodeDecodeError:
|
|
return None
|
|
elif auth_type == "digest":
|
|
auth_map = parse_dict_header(auth_info)
|
|
for key in "username", "realm", "nonce", "uri", "response":
|
|
if key not in auth_map:
|
|
return None
|
|
if "qop" in auth_map:
|
|
if not auth_map.get("nc") or not auth_map.get("cnonce"):
|
|
return None
|
|
return ds.Authorization("digest", auth_map)
|
|
return None
|
|
|
|
|
|
def parse_www_authenticate_header(
|
|
value: t.Optional[str],
|
|
on_update: t.Optional[t.Callable[["ds.WWWAuthenticate"], None]] = None,
|
|
) -> "ds.WWWAuthenticate":
|
|
"""Parse an HTTP WWW-Authenticate header into a
|
|
:class:`~werkzeug.datastructures.WWWAuthenticate` object.
|
|
|
|
:param value: a WWW-Authenticate header to parse.
|
|
:param on_update: an optional callable that is called every time a value
|
|
on the :class:`~werkzeug.datastructures.WWWAuthenticate`
|
|
object is changed.
|
|
:return: a :class:`~werkzeug.datastructures.WWWAuthenticate` object.
|
|
"""
|
|
if not value:
|
|
return ds.WWWAuthenticate(on_update=on_update)
|
|
try:
|
|
auth_type, auth_info = value.split(None, 1)
|
|
auth_type = auth_type.lower()
|
|
except (ValueError, AttributeError):
|
|
return ds.WWWAuthenticate(value.strip().lower(), on_update=on_update)
|
|
return ds.WWWAuthenticate(auth_type, parse_dict_header(auth_info), on_update)
|
|
|
|
|
|
def parse_if_range_header(value: t.Optional[str]) -> "ds.IfRange":
|
|
"""Parses an if-range header which can be an etag or a date. Returns
|
|
a :class:`~werkzeug.datastructures.IfRange` object.
|
|
|
|
.. versionchanged:: 2.0
|
|
If the value represents a datetime, it is timezone-aware.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
if not value:
|
|
return ds.IfRange()
|
|
date = parse_date(value)
|
|
if date is not None:
|
|
return ds.IfRange(date=date)
|
|
# drop weakness information
|
|
return ds.IfRange(unquote_etag(value)[0])
|
|
|
|
|
|
def parse_range_header(
|
|
value: t.Optional[str], make_inclusive: bool = True
|
|
) -> t.Optional["ds.Range"]:
|
|
"""Parses a range header into a :class:`~werkzeug.datastructures.Range`
|
|
object. If the header is missing or malformed `None` is returned.
|
|
`ranges` is a list of ``(start, stop)`` tuples where the ranges are
|
|
non-inclusive.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
if not value or "=" not in value:
|
|
return None
|
|
|
|
ranges = []
|
|
last_end = 0
|
|
units, rng = value.split("=", 1)
|
|
units = units.strip().lower()
|
|
|
|
for item in rng.split(","):
|
|
item = item.strip()
|
|
if "-" not in item:
|
|
return None
|
|
if item.startswith("-"):
|
|
if last_end < 0:
|
|
return None
|
|
try:
|
|
begin = int(item)
|
|
except ValueError:
|
|
return None
|
|
end = None
|
|
last_end = -1
|
|
elif "-" in item:
|
|
begin_str, end_str = item.split("-", 1)
|
|
begin_str = begin_str.strip()
|
|
end_str = end_str.strip()
|
|
|
|
try:
|
|
begin = int(begin_str)
|
|
except ValueError:
|
|
return None
|
|
|
|
if begin < last_end or last_end < 0:
|
|
return None
|
|
if end_str:
|
|
try:
|
|
end = int(end_str) + 1
|
|
except ValueError:
|
|
return None
|
|
|
|
if begin >= end:
|
|
return None
|
|
else:
|
|
end = None
|
|
last_end = end if end is not None else -1
|
|
ranges.append((begin, end))
|
|
|
|
return ds.Range(units, ranges)
|
|
|
|
|
|
def parse_content_range_header(
|
|
value: t.Optional[str],
|
|
on_update: t.Optional[t.Callable[["ds.ContentRange"], None]] = None,
|
|
) -> t.Optional["ds.ContentRange"]:
|
|
"""Parses a range header into a
|
|
:class:`~werkzeug.datastructures.ContentRange` object or `None` if
|
|
parsing is not possible.
|
|
|
|
.. versionadded:: 0.7
|
|
|
|
:param value: a content range header to be parsed.
|
|
:param on_update: an optional callable that is called every time a value
|
|
on the :class:`~werkzeug.datastructures.ContentRange`
|
|
object is changed.
|
|
"""
|
|
if value is None:
|
|
return None
|
|
try:
|
|
units, rangedef = (value or "").strip().split(None, 1)
|
|
except ValueError:
|
|
return None
|
|
|
|
if "/" not in rangedef:
|
|
return None
|
|
rng, length_str = rangedef.split("/", 1)
|
|
if length_str == "*":
|
|
length = None
|
|
else:
|
|
try:
|
|
length = int(length_str)
|
|
except ValueError:
|
|
return None
|
|
|
|
if rng == "*":
|
|
if not is_byte_range_valid(None, None, length):
|
|
return None
|
|
|
|
return ds.ContentRange(units, None, None, length, on_update=on_update)
|
|
elif "-" not in rng:
|
|
return None
|
|
|
|
start_str, stop_str = rng.split("-", 1)
|
|
try:
|
|
start = int(start_str)
|
|
stop = int(stop_str) + 1
|
|
except ValueError:
|
|
return None
|
|
|
|
if is_byte_range_valid(start, stop, length):
|
|
return ds.ContentRange(units, start, stop, length, on_update=on_update)
|
|
|
|
return None
|
|
|
|
|
|
def quote_etag(etag: str, weak: bool = False) -> str:
|
|
"""Quote an etag.
|
|
|
|
:param etag: the etag to quote.
|
|
:param weak: set to `True` to tag it "weak".
|
|
"""
|
|
if '"' in etag:
|
|
raise ValueError("invalid etag")
|
|
etag = f'"{etag}"'
|
|
if weak:
|
|
etag = f"W/{etag}"
|
|
return etag
|
|
|
|
|
|
def unquote_etag(
|
|
etag: t.Optional[str],
|
|
) -> t.Union[t.Tuple[str, bool], t.Tuple[None, None]]:
|
|
"""Unquote a single etag:
|
|
|
|
>>> unquote_etag('W/"bar"')
|
|
('bar', True)
|
|
>>> unquote_etag('"bar"')
|
|
('bar', False)
|
|
|
|
:param etag: the etag identifier to unquote.
|
|
:return: a ``(etag, weak)`` tuple.
|
|
"""
|
|
if not etag:
|
|
return None, None
|
|
etag = etag.strip()
|
|
weak = False
|
|
if etag.startswith(("W/", "w/")):
|
|
weak = True
|
|
etag = etag[2:]
|
|
if etag[:1] == etag[-1:] == '"':
|
|
etag = etag[1:-1]
|
|
return etag, weak
|
|
|
|
|
|
def parse_etags(value: t.Optional[str]) -> "ds.ETags":
|
|
"""Parse an etag header.
|
|
|
|
:param value: the tag header to parse
|
|
:return: an :class:`~werkzeug.datastructures.ETags` object.
|
|
"""
|
|
if not value:
|
|
return ds.ETags()
|
|
strong = []
|
|
weak = []
|
|
end = len(value)
|
|
pos = 0
|
|
while pos < end:
|
|
match = _etag_re.match(value, pos)
|
|
if match is None:
|
|
break
|
|
is_weak, quoted, raw = match.groups()
|
|
if raw == "*":
|
|
return ds.ETags(star_tag=True)
|
|
elif quoted:
|
|
raw = quoted
|
|
if is_weak:
|
|
weak.append(raw)
|
|
else:
|
|
strong.append(raw)
|
|
pos = match.end()
|
|
return ds.ETags(strong, weak)
|
|
|
|
|
|
def generate_etag(data: bytes) -> str:
|
|
"""Generate an etag for some data.
|
|
|
|
.. versionchanged:: 2.0
|
|
Use SHA-1. MD5 may not be available in some environments.
|
|
"""
|
|
return sha1(data).hexdigest()
|
|
|
|
|
|
def parse_date(value: t.Optional[str]) -> t.Optional[datetime]:
|
|
"""Parse an :rfc:`2822` date into a timezone-aware
|
|
:class:`datetime.datetime` object, or ``None`` if parsing fails.
|
|
|
|
This is a wrapper for :func:`email.utils.parsedate_to_datetime`. It
|
|
returns ``None`` if parsing fails instead of raising an exception,
|
|
and always returns a timezone-aware datetime object. If the string
|
|
doesn't have timezone information, it is assumed to be UTC.
|
|
|
|
:param value: A string with a supported date format.
|
|
|
|
.. versionchanged:: 2.0
|
|
Return a timezone-aware datetime object. Use
|
|
``email.utils.parsedate_to_datetime``.
|
|
"""
|
|
if value is None:
|
|
return None
|
|
|
|
try:
|
|
dt = email.utils.parsedate_to_datetime(value)
|
|
except (TypeError, ValueError):
|
|
return None
|
|
|
|
if dt.tzinfo is None:
|
|
return dt.replace(tzinfo=timezone.utc)
|
|
|
|
return dt
|
|
|
|
|
|
def http_date(
|
|
timestamp: t.Optional[t.Union[datetime, date, int, float, struct_time]] = None
|
|
) -> str:
|
|
"""Format a datetime object or timestamp into an :rfc:`2822` date
|
|
string.
|
|
|
|
This is a wrapper for :func:`email.utils.format_datetime`. It
|
|
assumes naive datetime objects are in UTC instead of raising an
|
|
exception.
|
|
|
|
:param timestamp: The datetime or timestamp to format. Defaults to
|
|
the current time.
|
|
|
|
.. versionchanged:: 2.0
|
|
Use ``email.utils.format_datetime``. Accept ``date`` objects.
|
|
"""
|
|
if isinstance(timestamp, date):
|
|
if not isinstance(timestamp, datetime):
|
|
# Assume plain date is midnight UTC.
|
|
timestamp = datetime.combine(timestamp, time(), tzinfo=timezone.utc)
|
|
else:
|
|
# Ensure datetime is timezone-aware.
|
|
timestamp = _dt_as_utc(timestamp)
|
|
|
|
return email.utils.format_datetime(timestamp, usegmt=True)
|
|
|
|
if isinstance(timestamp, struct_time):
|
|
timestamp = mktime(timestamp)
|
|
|
|
return email.utils.formatdate(timestamp, usegmt=True)
|
|
|
|
|
|
def parse_age(value: t.Optional[str] = None) -> t.Optional[timedelta]:
|
|
"""Parses a base-10 integer count of seconds into a timedelta.
|
|
|
|
If parsing fails, the return value is `None`.
|
|
|
|
:param value: a string consisting of an integer represented in base-10
|
|
:return: a :class:`datetime.timedelta` object or `None`.
|
|
"""
|
|
if not value:
|
|
return None
|
|
try:
|
|
seconds = int(value)
|
|
except ValueError:
|
|
return None
|
|
if seconds < 0:
|
|
return None
|
|
try:
|
|
return timedelta(seconds=seconds)
|
|
except OverflowError:
|
|
return None
|
|
|
|
|
|
def dump_age(age: t.Optional[t.Union[timedelta, int]] = None) -> t.Optional[str]:
|
|
"""Formats the duration as a base-10 integer.
|
|
|
|
:param age: should be an integer number of seconds,
|
|
a :class:`datetime.timedelta` object, or,
|
|
if the age is unknown, `None` (default).
|
|
"""
|
|
if age is None:
|
|
return None
|
|
if isinstance(age, timedelta):
|
|
age = int(age.total_seconds())
|
|
else:
|
|
age = int(age)
|
|
|
|
if age < 0:
|
|
raise ValueError("age cannot be negative")
|
|
|
|
return str(age)
|
|
|
|
|
|
def is_resource_modified(
|
|
environ: "WSGIEnvironment",
|
|
etag: t.Optional[str] = None,
|
|
data: t.Optional[bytes] = None,
|
|
last_modified: t.Optional[t.Union[datetime, str]] = None,
|
|
ignore_if_range: bool = True,
|
|
) -> bool:
|
|
"""Convenience method for conditional requests.
|
|
|
|
:param environ: the WSGI environment of the request to be checked.
|
|
:param etag: the etag for the response for comparison.
|
|
:param data: or alternatively the data of the response to automatically
|
|
generate an etag using :func:`generate_etag`.
|
|
:param last_modified: an optional date of the last modification.
|
|
:param ignore_if_range: If `False`, `If-Range` header will be taken into
|
|
account.
|
|
:return: `True` if the resource was modified, otherwise `False`.
|
|
|
|
.. versionchanged:: 2.0
|
|
SHA-1 is used to generate an etag value for the data. MD5 may
|
|
not be available in some environments.
|
|
|
|
.. versionchanged:: 1.0.0
|
|
The check is run for methods other than ``GET`` and ``HEAD``.
|
|
"""
|
|
return _sansio_http.is_resource_modified(
|
|
http_range=environ.get("HTTP_RANGE"),
|
|
http_if_range=environ.get("HTTP_IF_RANGE"),
|
|
http_if_modified_since=environ.get("HTTP_IF_MODIFIED_SINCE"),
|
|
http_if_none_match=environ.get("HTTP_IF_NONE_MATCH"),
|
|
http_if_match=environ.get("HTTP_IF_MATCH"),
|
|
etag=etag,
|
|
data=data,
|
|
last_modified=last_modified,
|
|
ignore_if_range=ignore_if_range,
|
|
)
|
|
|
|
|
|
def remove_entity_headers(
|
|
headers: t.Union["ds.Headers", t.List[t.Tuple[str, str]]],
|
|
allowed: t.Iterable[str] = ("expires", "content-location"),
|
|
) -> None:
|
|
"""Remove all entity headers from a list or :class:`Headers` object. This
|
|
operation works in-place. `Expires` and `Content-Location` headers are
|
|
by default not removed. The reason for this is :rfc:`2616` section
|
|
10.3.5 which specifies some entity headers that should be sent.
|
|
|
|
.. versionchanged:: 0.5
|
|
added `allowed` parameter.
|
|
|
|
:param headers: a list or :class:`Headers` object.
|
|
:param allowed: a list of headers that should still be allowed even though
|
|
they are entity headers.
|
|
"""
|
|
allowed = {x.lower() for x in allowed}
|
|
headers[:] = [
|
|
(key, value)
|
|
for key, value in headers
|
|
if not is_entity_header(key) or key.lower() in allowed
|
|
]
|
|
|
|
|
|
def remove_hop_by_hop_headers(
|
|
headers: t.Union["ds.Headers", t.List[t.Tuple[str, str]]]
|
|
) -> None:
|
|
"""Remove all HTTP/1.1 "Hop-by-Hop" headers from a list or
|
|
:class:`Headers` object. This operation works in-place.
|
|
|
|
.. versionadded:: 0.5
|
|
|
|
:param headers: a list or :class:`Headers` object.
|
|
"""
|
|
headers[:] = [
|
|
(key, value) for key, value in headers if not is_hop_by_hop_header(key)
|
|
]
|
|
|
|
|
|
def is_entity_header(header: str) -> bool:
|
|
"""Check if a header is an entity header.
|
|
|
|
.. versionadded:: 0.5
|
|
|
|
:param header: the header to test.
|
|
:return: `True` if it's an entity header, `False` otherwise.
|
|
"""
|
|
return header.lower() in _entity_headers
|
|
|
|
|
|
def is_hop_by_hop_header(header: str) -> bool:
|
|
"""Check if a header is an HTTP/1.1 "Hop-by-Hop" header.
|
|
|
|
.. versionadded:: 0.5
|
|
|
|
:param header: the header to test.
|
|
:return: `True` if it's an HTTP/1.1 "Hop-by-Hop" header, `False` otherwise.
|
|
"""
|
|
return header.lower() in _hop_by_hop_headers
|
|
|
|
|
|
def parse_cookie(
|
|
header: t.Union["WSGIEnvironment", str, bytes, None],
|
|
charset: str = "utf-8",
|
|
errors: str = "replace",
|
|
cls: t.Optional[t.Type["ds.MultiDict"]] = None,
|
|
) -> "ds.MultiDict[str, str]":
|
|
"""Parse a cookie from a string or WSGI environ.
|
|
|
|
The same key can be provided multiple times, the values are stored
|
|
in-order. The default :class:`MultiDict` will have the first value
|
|
first, and all values can be retrieved with
|
|
:meth:`MultiDict.getlist`.
|
|
|
|
:param header: The cookie header as a string, or a WSGI environ dict
|
|
with a ``HTTP_COOKIE`` key.
|
|
:param charset: The charset for the cookie values.
|
|
:param errors: The error behavior for the charset decoding.
|
|
:param cls: A dict-like class to store the parsed cookies in.
|
|
Defaults to :class:`MultiDict`.
|
|
|
|
.. versionchanged:: 1.0.0
|
|
Returns a :class:`MultiDict` instead of a
|
|
``TypeConversionDict``.
|
|
|
|
.. versionchanged:: 0.5
|
|
Returns a :class:`TypeConversionDict` instead of a regular dict.
|
|
The ``cls`` parameter was added.
|
|
"""
|
|
if isinstance(header, dict):
|
|
cookie = header.get("HTTP_COOKIE", "")
|
|
elif header is None:
|
|
cookie = ""
|
|
else:
|
|
cookie = header
|
|
|
|
return _sansio_http.parse_cookie(
|
|
cookie=cookie, charset=charset, errors=errors, cls=cls
|
|
)
|
|
|
|
|
|
def dump_cookie(
|
|
key: str,
|
|
value: t.Union[bytes, str] = "",
|
|
max_age: t.Optional[t.Union[timedelta, int]] = None,
|
|
expires: t.Optional[t.Union[str, datetime, int, float]] = None,
|
|
path: t.Optional[str] = "/",
|
|
domain: t.Optional[str] = None,
|
|
secure: bool = False,
|
|
httponly: bool = False,
|
|
charset: str = "utf-8",
|
|
sync_expires: bool = True,
|
|
max_size: int = 4093,
|
|
samesite: t.Optional[str] = None,
|
|
) -> str:
|
|
"""Create a Set-Cookie header without the ``Set-Cookie`` prefix.
|
|
|
|
The return value is usually restricted to ascii as the vast majority
|
|
of values are properly escaped, but that is no guarantee. It's
|
|
tunneled through latin1 as required by :pep:`3333`.
|
|
|
|
The return value is not ASCII safe if the key contains unicode
|
|
characters. This is technically against the specification but
|
|
happens in the wild. It's strongly recommended to not use
|
|
non-ASCII values for the keys.
|
|
|
|
:param max_age: should be a number of seconds, or `None` (default) if
|
|
the cookie should last only as long as the client's
|
|
browser session. Additionally `timedelta` objects
|
|
are accepted, too.
|
|
:param expires: should be a `datetime` object or unix timestamp.
|
|
:param path: limits the cookie to a given path, per default it will
|
|
span the whole domain.
|
|
:param domain: Use this if you want to set a cross-domain cookie. For
|
|
example, ``domain=".example.com"`` will set a cookie
|
|
that is readable by the domain ``www.example.com``,
|
|
``foo.example.com`` etc. Otherwise, a cookie will only
|
|
be readable by the domain that set it.
|
|
:param secure: The cookie will only be available via HTTPS
|
|
:param httponly: disallow JavaScript to access the cookie. This is an
|
|
extension to the cookie standard and probably not
|
|
supported by all browsers.
|
|
:param charset: the encoding for string values.
|
|
:param sync_expires: automatically set expires if max_age is defined
|
|
but expires not.
|
|
:param max_size: Warn if the final header value exceeds this size. The
|
|
default, 4093, should be safely `supported by most browsers
|
|
<cookie_>`_. Set to 0 to disable this check.
|
|
:param samesite: Limits the scope of the cookie such that it will
|
|
only be attached to requests if those requests are same-site.
|
|
|
|
.. _`cookie`: http://browsercookielimits.squawky.net/
|
|
|
|
.. versionchanged:: 1.0.0
|
|
The string ``'None'`` is accepted for ``samesite``.
|
|
"""
|
|
key = _to_bytes(key, charset)
|
|
value = _to_bytes(value, charset)
|
|
|
|
if path is not None:
|
|
from .urls import iri_to_uri
|
|
|
|
path = iri_to_uri(path, charset)
|
|
|
|
domain = _make_cookie_domain(domain)
|
|
|
|
if isinstance(max_age, timedelta):
|
|
max_age = int(max_age.total_seconds())
|
|
|
|
if expires is not None:
|
|
if not isinstance(expires, str):
|
|
expires = http_date(expires)
|
|
elif max_age is not None and sync_expires:
|
|
expires = http_date(datetime.now(tz=timezone.utc).timestamp() + max_age)
|
|
|
|
if samesite is not None:
|
|
samesite = samesite.title()
|
|
|
|
if samesite not in {"Strict", "Lax", "None"}:
|
|
raise ValueError("SameSite must be 'Strict', 'Lax', or 'None'.")
|
|
|
|
buf = [key + b"=" + _cookie_quote(value)]
|
|
|
|
# XXX: In theory all of these parameters that are not marked with `None`
|
|
# should be quoted. Because stdlib did not quote it before I did not
|
|
# want to introduce quoting there now.
|
|
for k, v, q in (
|
|
(b"Domain", domain, True),
|
|
(b"Expires", expires, False),
|
|
(b"Max-Age", max_age, False),
|
|
(b"Secure", secure, None),
|
|
(b"HttpOnly", httponly, None),
|
|
(b"Path", path, False),
|
|
(b"SameSite", samesite, False),
|
|
):
|
|
if q is None:
|
|
if v:
|
|
buf.append(k)
|
|
continue
|
|
|
|
if v is None:
|
|
continue
|
|
|
|
tmp = bytearray(k)
|
|
if not isinstance(v, (bytes, bytearray)):
|
|
v = _to_bytes(str(v), charset)
|
|
if q:
|
|
v = _cookie_quote(v)
|
|
tmp += b"=" + v
|
|
buf.append(bytes(tmp))
|
|
|
|
# The return value will be an incorrectly encoded latin1 header for
|
|
# consistency with the headers object.
|
|
rv = b"; ".join(buf)
|
|
rv = rv.decode("latin1")
|
|
|
|
# Warn if the final value of the cookie is larger than the limit. If the
|
|
# cookie is too large, then it may be silently ignored by the browser,
|
|
# which can be quite hard to debug.
|
|
cookie_size = len(rv)
|
|
|
|
if max_size and cookie_size > max_size:
|
|
value_size = len(value)
|
|
warnings.warn(
|
|
f"The {key.decode(charset)!r} cookie is too large: the value was"
|
|
f" {value_size} bytes but the"
|
|
f" header required {cookie_size - value_size} extra bytes. The final size"
|
|
f" was {cookie_size} bytes but the limit is {max_size} bytes. Browsers may"
|
|
f" silently ignore cookies larger than this.",
|
|
stacklevel=2,
|
|
)
|
|
|
|
return rv
|
|
|
|
|
|
def is_byte_range_valid(
|
|
start: t.Optional[int], stop: t.Optional[int], length: t.Optional[int]
|
|
) -> bool:
|
|
"""Checks if a given byte content range is valid for the given length.
|
|
|
|
.. versionadded:: 0.7
|
|
"""
|
|
if (start is None) != (stop is None):
|
|
return False
|
|
elif start is None:
|
|
return length is None or length >= 0
|
|
elif length is None:
|
|
return 0 <= start < stop # type: ignore
|
|
elif start >= stop: # type: ignore
|
|
return False
|
|
return 0 <= start < length
|
|
|
|
|
|
# circular dependencies
|
|
from . import datastructures as ds
|
|
from .sansio import http as _sansio_http
|