import base64 import binascii import json import re import uuid import warnings import zlib from collections import deque from types import TracebackType from typing import ( # noqa TYPE_CHECKING, Any, Dict, Iterator, List, Mapping, Optional, Sequence, Tuple, Type, Union, cast, ) from urllib.parse import parse_qsl, unquote, urlencode from multidict import CIMultiDict, CIMultiDictProxy, MultiMapping # noqa from .hdrs import ( CONTENT_DISPOSITION, CONTENT_ENCODING, CONTENT_LENGTH, CONTENT_TRANSFER_ENCODING, CONTENT_TYPE, ) from .helpers import CHAR, TOKEN, parse_mimetype, reify from .http import HeadersParser from .payload import ( JsonPayload, LookupError, Order, Payload, StringPayload, get_payload, payload_type, ) from .streams import StreamReader __all__ = ('MultipartReader', 'MultipartWriter', 'BodyPartReader', 'BadContentDispositionHeader', 'BadContentDispositionParam', 'parse_content_disposition', 'content_disposition_filename') if TYPE_CHECKING: # pragma: no cover from .client_reqrep import ClientResponse # noqa class BadContentDispositionHeader(RuntimeWarning): pass class BadContentDispositionParam(RuntimeWarning): pass def parse_content_disposition(header: Optional[str]) -> Tuple[Optional[str], Dict[str, str]]: def is_token(string: str) -> bool: return bool(string) and TOKEN >= set(string) def is_quoted(string: str) -> bool: return string[0] == string[-1] == '"' def is_rfc5987(string: str) -> bool: return is_token(string) and string.count("'") == 2 def is_extended_param(string: str) -> bool: return string.endswith('*') def is_continuous_param(string: str) -> bool: pos = string.find('*') + 1 if not pos: return False substring = string[pos:-1] if string.endswith('*') else string[pos:] return substring.isdigit() def unescape(text: str, *, chars: str=''.join(map(re.escape, CHAR))) -> str: return re.sub('\\\\([{}])'.format(chars), '\\1', text) if not header: return None, {} disptype, *parts = header.split(';') if not is_token(disptype): warnings.warn(BadContentDispositionHeader(header)) return None, {} params = {} # type: Dict[str, str] while parts: item = parts.pop(0) if '=' not in item: warnings.warn(BadContentDispositionHeader(header)) return None, {} key, value = item.split('=', 1) key = key.lower().strip() value = value.lstrip() if key in params: warnings.warn(BadContentDispositionHeader(header)) return None, {} if not is_token(key): warnings.warn(BadContentDispositionParam(item)) continue elif is_continuous_param(key): if is_quoted(value): value = unescape(value[1:-1]) elif not is_token(value): warnings.warn(BadContentDispositionParam(item)) continue elif is_extended_param(key): if is_rfc5987(value): encoding, _, value = value.split("'", 2) encoding = encoding or 'utf-8' else: warnings.warn(BadContentDispositionParam(item)) continue try: value = unquote(value, encoding, 'strict') except UnicodeDecodeError: # pragma: nocover warnings.warn(BadContentDispositionParam(item)) continue else: failed = True if is_quoted(value): failed = False value = unescape(value[1:-1].lstrip('\\/')) elif is_token(value): failed = False elif parts: # maybe just ; in filename, in any case this is just # one case fix, for proper fix we need to redesign parser _value = '%s;%s' % (value, parts[0]) if is_quoted(_value): parts.pop(0) value = unescape(_value[1:-1].lstrip('\\/')) failed = False if failed: warnings.warn(BadContentDispositionHeader(header)) return None, {} params[key] = value return disptype.lower(), params def content_disposition_filename(params: Mapping[str, str], name: str='filename') -> Optional[str]: name_suf = '%s*' % name if not params: return None elif name_suf in params: return params[name_suf] elif name in params: return params[name] else: parts = [] fnparams = sorted((key, value) for key, value in params.items() if key.startswith(name_suf)) for num, (key, value) in enumerate(fnparams): _, tail = key.split('*', 1) if tail.endswith('*'): tail = tail[:-1] if tail == str(num): parts.append(value) else: break if not parts: return None value = ''.join(parts) if "'" in value: encoding, _, value = value.split("'", 2) encoding = encoding or 'utf-8' return unquote(value, encoding, 'strict') return value class MultipartResponseWrapper: """Wrapper around the MultipartBodyReader. It takes care about underlying connection and close it when it needs in. """ def __init__(self, resp: 'ClientResponse', stream: Any) -> None: # TODO: add strong annotation to stream self.resp = resp self.stream = stream def __aiter__(self) -> 'MultipartResponseWrapper': return self async def __anext__(self) -> Any: part = await self.next() if part is None: raise StopAsyncIteration # NOQA return part def at_eof(self) -> bool: """Returns True when all response data had been read.""" return self.resp.content.at_eof() async def next(self) -> Any: """Emits next multipart reader object.""" item = await self.stream.next() if self.stream.at_eof(): await self.release() return item async def release(self) -> None: """Releases the connection gracefully, reading all the content to the void.""" await self.resp.release() class BodyPartReader: """Multipart reader for single body part.""" chunk_size = 8192 def __init__(self, boundary: bytes, headers: Mapping[str, Optional[str]], content: StreamReader) -> None: self.headers = headers self._boundary = boundary self._content = content self._at_eof = False length = self.headers.get(CONTENT_LENGTH, None) self._length = int(length) if length is not None else None self._read_bytes = 0 # TODO: typeing.Deque is not supported by Python 3.5 self._unread = deque() # type: Any self._prev_chunk = None # type: Optional[bytes] self._content_eof = 0 self._cache = {} # type: Dict[str, Any] def __aiter__(self) -> 'BodyPartReader': return self async def __anext__(self) -> Any: part = await self.next() if part is None: raise StopAsyncIteration # NOQA return part async def next(self) -> Any: item = await self.read() if not item: return None return item async def read(self, *, decode: bool=False) -> Any: """Reads body part data. decode: Decodes data following by encoding method from Content-Encoding header. If it missed data remains untouched """ if self._at_eof: return b'' data = bytearray() while not self._at_eof: data.extend((await self.read_chunk(self.chunk_size))) if decode: return self.decode(data) return data async def read_chunk(self, size: int=chunk_size) -> bytes: """Reads body part content chunk of the specified size. size: chunk size """ if self._at_eof: return b'' if self._length: chunk = await self._read_chunk_from_length(size) else: chunk = await self._read_chunk_from_stream(size) self._read_bytes += len(chunk) if self._read_bytes == self._length: self._at_eof = True if self._at_eof: clrf = await self._content.readline() assert b'\r\n' == clrf, \ 'reader did not read all the data or it is malformed' return chunk async def _read_chunk_from_length(self, size: int) -> bytes: # Reads body part content chunk of the specified size. # The body part must has Content-Length header with proper value. assert self._length is not None, \ 'Content-Length required for chunked read' chunk_size = min(size, self._length - self._read_bytes) chunk = await self._content.read(chunk_size) return chunk async def _read_chunk_from_stream(self, size: int) -> bytes: # Reads content chunk of body part with unknown length. # The Content-Length header for body part is not necessary. assert size >= len(self._boundary) + 2, \ 'Chunk size must be greater or equal than boundary length + 2' first_chunk = self._prev_chunk is None if first_chunk: self._prev_chunk = await self._content.read(size) chunk = await self._content.read(size) self._content_eof += int(self._content.at_eof()) assert self._content_eof < 3, "Reading after EOF" assert self._prev_chunk is not None window = self._prev_chunk + chunk sub = b'\r\n' + self._boundary if first_chunk: idx = window.find(sub) else: idx = window.find(sub, max(0, len(self._prev_chunk) - len(sub))) if idx >= 0: # pushing boundary back to content with warnings.catch_warnings(): warnings.filterwarnings("ignore", category=DeprecationWarning) self._content.unread_data(window[idx:]) if size > idx: self._prev_chunk = self._prev_chunk[:idx] chunk = window[len(self._prev_chunk):idx] if not chunk: self._at_eof = True result = self._prev_chunk self._prev_chunk = chunk return result async def readline(self) -> bytes: """Reads body part by line by line.""" if self._at_eof: return b'' if self._unread: line = self._unread.popleft() else: line = await self._content.readline() if line.startswith(self._boundary): # the very last boundary may not come with \r\n, # so set single rules for everyone sline = line.rstrip(b'\r\n') boundary = self._boundary last_boundary = self._boundary + b'--' # ensure that we read exactly the boundary, not something alike if sline == boundary or sline == last_boundary: self._at_eof = True self._unread.append(line) return b'' else: next_line = await self._content.readline() if next_line.startswith(self._boundary): line = line[:-2] # strip CRLF but only once self._unread.append(next_line) return line async def release(self) -> None: """Like read(), but reads all the data to the void.""" if self._at_eof: return while not self._at_eof: await self.read_chunk(self.chunk_size) async def text(self, *, encoding: Optional[str]=None) -> str: """Like read(), but assumes that body part contains text data.""" data = await self.read(decode=True) # see https://www.w3.org/TR/html5/forms.html#multipart/form-data-encoding-algorithm # NOQA # and https://dvcs.w3.org/hg/xhr/raw-file/tip/Overview.html#dom-xmlhttprequest-send # NOQA encoding = encoding or self.get_charset(default='utf-8') return data.decode(encoding) async def json(self, *, encoding: Optional[str]=None) -> Any: """Like read(), but assumes that body parts contains JSON data.""" data = await self.read(decode=True) if not data: return None encoding = encoding or self.get_charset(default='utf-8') return json.loads(data.decode(encoding)) async def form(self, *, encoding: Optional[str]=None) -> List[Tuple[str, str]]: """Like read(), but assumes that body parts contains form urlencoded data. """ data = await self.read(decode=True) if not data: return [] if encoding is not None: real_encoding = encoding else: real_encoding = self.get_charset(default='utf-8') return parse_qsl(data.rstrip().decode(real_encoding), keep_blank_values=True, encoding=real_encoding) def at_eof(self) -> bool: """Returns True if the boundary was reached or False otherwise.""" return self._at_eof def decode(self, data: bytes) -> bytes: """Decodes data according the specified Content-Encoding or Content-Transfer-Encoding headers value. """ if CONTENT_TRANSFER_ENCODING in self.headers: data = self._decode_content_transfer(data) if CONTENT_ENCODING in self.headers: return self._decode_content(data) return data def _decode_content(self, data: bytes) -> bytes: encoding = cast(str, self.headers[CONTENT_ENCODING]).lower() if encoding == 'deflate': return zlib.decompress(data, -zlib.MAX_WBITS) elif encoding == 'gzip': return zlib.decompress(data, 16 + zlib.MAX_WBITS) elif encoding == 'identity': return data else: raise RuntimeError('unknown content encoding: {}'.format(encoding)) def _decode_content_transfer(self, data: bytes) -> bytes: encoding = cast(str, self.headers[CONTENT_TRANSFER_ENCODING]).lower() if encoding == 'base64': return base64.b64decode(data) elif encoding == 'quoted-printable': return binascii.a2b_qp(data) elif encoding in ('binary', '8bit', '7bit'): return data else: raise RuntimeError('unknown content transfer encoding: {}' ''.format(encoding)) def get_charset(self, default: str) -> str: """Returns charset parameter from Content-Type header or default.""" ctype = self.headers.get(CONTENT_TYPE, '') mimetype = parse_mimetype(ctype) return mimetype.parameters.get('charset', default) @reify def name(self) -> Optional[str]: """Returns name specified in Content-Disposition header or None if missed or header is malformed. """ _, params = parse_content_disposition( self.headers.get(CONTENT_DISPOSITION)) return content_disposition_filename(params, 'name') @reify def filename(self) -> Optional[str]: """Returns filename specified in Content-Disposition header or None if missed or header is malformed. """ _, params = parse_content_disposition( self.headers.get(CONTENT_DISPOSITION)) return content_disposition_filename(params, 'filename') @payload_type(BodyPartReader, order=Order.try_first) class BodyPartReaderPayload(Payload): def __init__(self, value: BodyPartReader, *args: Any, **kwargs: Any) -> None: super().__init__(value, *args, **kwargs) params = {} # type: Dict[str, str] if value.name is not None: params['name'] = value.name if value.filename is not None: params['filename'] = value.filename if params: self.set_content_disposition('attachment', True, **params) async def write(self, writer: Any) -> None: field = self._value chunk = await field.read_chunk(size=2**16) while chunk: await writer.write(field.decode(chunk)) chunk = await field.read_chunk(size=2**16) class MultipartReader: """Multipart body reader.""" #: Response wrapper, used when multipart readers constructs from response. response_wrapper_cls = MultipartResponseWrapper #: Multipart reader class, used to handle multipart/* body parts. #: None points to type(self) multipart_reader_cls = None #: Body part reader class for non multipart/* content types. part_reader_cls = BodyPartReader def __init__(self, headers: Mapping[str, str], content: StreamReader) -> None: self.headers = headers self._boundary = ('--' + self._get_boundary()).encode() self._content = content self._last_part = None self._at_eof = False self._at_bof = True self._unread = [] # type: List[bytes] def __aiter__(self) -> 'MultipartReader': return self async def __anext__(self) -> Any: part = await self.next() if part is None: raise StopAsyncIteration # NOQA return part @classmethod def from_response(cls, response: 'ClientResponse') -> Any: """Constructs reader instance from HTTP response. :param response: :class:`~aiohttp.client.ClientResponse` instance """ obj = cls.response_wrapper_cls(response, cls(response.headers, response.content)) return obj def at_eof(self) -> bool: """Returns True if the final boundary was reached or False otherwise. """ return self._at_eof async def next(self) -> Any: """Emits the next multipart body part.""" # So, if we're at BOF, we need to skip till the boundary. if self._at_eof: return await self._maybe_release_last_part() if self._at_bof: await self._read_until_first_boundary() self._at_bof = False else: await self._read_boundary() if self._at_eof: # we just read the last boundary, nothing to do there return self._last_part = await self.fetch_next_part() return self._last_part async def release(self) -> None: """Reads all the body parts to the void till the final boundary.""" while not self._at_eof: item = await self.next() if item is None: break await item.release() async def fetch_next_part(self) -> Any: """Returns the next body part reader.""" headers = await self._read_headers() return self._get_part_reader(headers) def _get_part_reader(self, headers: 'CIMultiDictProxy[str]') -> Any: """Dispatches the response by the `Content-Type` header, returning suitable reader instance. :param dict headers: Response headers """ ctype = headers.get(CONTENT_TYPE, '') mimetype = parse_mimetype(ctype) if mimetype.type == 'multipart': if self.multipart_reader_cls is None: return type(self)(headers, self._content) return self.multipart_reader_cls(headers, self._content) else: return self.part_reader_cls(self._boundary, headers, self._content) def _get_boundary(self) -> str: mimetype = parse_mimetype(self.headers[CONTENT_TYPE]) assert mimetype.type == 'multipart', ( 'multipart/* content type expected' ) if 'boundary' not in mimetype.parameters: raise ValueError('boundary missed for Content-Type: %s' % self.headers[CONTENT_TYPE]) boundary = mimetype.parameters['boundary'] if len(boundary) > 70: raise ValueError('boundary %r is too long (70 chars max)' % boundary) return boundary async def _readline(self) -> bytes: if self._unread: return self._unread.pop() return await self._content.readline() async def _read_until_first_boundary(self) -> None: while True: chunk = await self._readline() if chunk == b'': raise ValueError("Could not find starting boundary %r" % (self._boundary)) chunk = chunk.rstrip() if chunk == self._boundary: return elif chunk == self._boundary + b'--': self._at_eof = True return async def _read_boundary(self) -> None: chunk = (await self._readline()).rstrip() if chunk == self._boundary: pass elif chunk == self._boundary + b'--': self._at_eof = True epilogue = await self._readline() next_line = await self._readline() # the epilogue is expected and then either the end of input or the # parent multipart boundary, if the parent boundary is found then # it should be marked as unread and handed to the parent for # processing if next_line[:2] == b'--': self._unread.append(next_line) # otherwise the request is likely missing an epilogue and both # lines should be passed to the parent for processing # (this handles the old behavior gracefully) else: self._unread.extend([next_line, epilogue]) else: raise ValueError('Invalid boundary %r, expected %r' % (chunk, self._boundary)) async def _read_headers(self) -> 'CIMultiDictProxy[str]': lines = [b''] while True: chunk = await self._content.readline() chunk = chunk.strip() lines.append(chunk) if not chunk: break parser = HeadersParser() headers, raw_headers = parser.parse_headers(lines) return headers async def _maybe_release_last_part(self) -> None: """Ensures that the last read body part is read completely.""" if self._last_part is not None: if not self._last_part.at_eof(): await self._last_part.release() self._unread.extend(self._last_part._unread) self._last_part = None _Part = Tuple[Payload, str, str] class MultipartWriter(Payload): """Multipart body writer.""" def __init__(self, subtype: str='mixed', boundary: Optional[str]=None) -> None: boundary = boundary if boundary is not None else uuid.uuid4().hex # The underlying Payload API demands a str (utf-8), not bytes, # so we need to ensure we don't lose anything during conversion. # As a result, require the boundary to be ASCII only. # In both situations. try: self._boundary = boundary.encode('ascii') except UnicodeEncodeError: raise ValueError('boundary should contain ASCII only chars') \ from None ctype = ('multipart/{}; boundary={}' .format(subtype, self._boundary_value)) super().__init__(None, content_type=ctype) self._parts = [] # type: List[_Part] # noqa def __enter__(self) -> 'MultipartWriter': return self def __exit__(self, exc_type: Optional[Type[BaseException]], exc_val: Optional[BaseException], exc_tb: Optional[TracebackType]) -> None: pass def __iter__(self) -> Iterator[_Part]: return iter(self._parts) def __len__(self) -> int: return len(self._parts) _valid_tchar_regex = re.compile(br"\A[!#$%&'*+\-.^_`|~\w]+\Z") _invalid_qdtext_char_regex = re.compile(br"[\x00-\x08\x0A-\x1F\x7F]") @property def _boundary_value(self) -> str: """Wrap boundary parameter value in quotes, if necessary. Reads self.boundary and returns a unicode sting. """ # Refer to RFCs 7231, 7230, 5234. # # parameter = token "=" ( token / quoted-string ) # token = 1*tchar # quoted-string = DQUOTE *( qdtext / quoted-pair ) DQUOTE # qdtext = HTAB / SP / %x21 / %x23-5B / %x5D-7E / obs-text # obs-text = %x80-FF # quoted-pair = "\" ( HTAB / SP / VCHAR / obs-text ) # tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" # / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~" # / DIGIT / ALPHA # ; any VCHAR, except delimiters # VCHAR = %x21-7E value = self._boundary if re.match(self._valid_tchar_regex, value): return value.decode('ascii') # cannot fail if re.search(self._invalid_qdtext_char_regex, value): raise ValueError("boundary value contains invalid characters") # escape %x5C and %x22 quoted_value_content = value.replace(b'\\', b'\\\\') quoted_value_content = quoted_value_content.replace(b'"', b'\\"') return '"' + quoted_value_content.decode('ascii') + '"' @property def boundary(self) -> str: return self._boundary.decode('ascii') def append( self, obj: Any, headers: Optional['MultiMapping[str]']=None ) -> Payload: if headers is None: headers = CIMultiDict() if isinstance(obj, Payload): obj.headers.update(headers) return self.append_payload(obj) else: try: payload = get_payload(obj, headers=headers) except LookupError: raise TypeError('Cannot create payload from %r' % obj) else: return self.append_payload(payload) def append_payload(self, payload: Payload) -> Payload: """Adds a new body part to multipart writer.""" # compression encoding = payload.headers.get(CONTENT_ENCODING, '').lower() # type: Optional[str] # noqa if encoding and encoding not in ('deflate', 'gzip', 'identity'): raise RuntimeError('unknown content encoding: {}'.format(encoding)) if encoding == 'identity': encoding = None # te encoding te_encoding = payload.headers.get( CONTENT_TRANSFER_ENCODING, '').lower() # type: Optional[str] # noqa if te_encoding not in ('', 'base64', 'quoted-printable', 'binary'): raise RuntimeError('unknown content transfer encoding: {}' ''.format(te_encoding)) if te_encoding == 'binary': te_encoding = None # size size = payload.size if size is not None and not (encoding or te_encoding): payload.headers[CONTENT_LENGTH] = str(size) self._parts.append((payload, encoding, te_encoding)) # type: ignore return payload def append_json( self, obj: Any, headers: Optional['MultiMapping[str]']=None ) -> Payload: """Helper to append JSON part.""" if headers is None: headers = CIMultiDict() return self.append_payload(JsonPayload(obj, headers=headers)) def append_form( self, obj: Union[Sequence[Tuple[str, str]], Mapping[str, str]], headers: Optional['MultiMapping[str]']=None ) -> Payload: """Helper to append form urlencoded part.""" assert isinstance(obj, (Sequence, Mapping)) if headers is None: headers = CIMultiDict() if isinstance(obj, Mapping): obj = list(obj.items()) data = urlencode(obj, doseq=True) return self.append_payload( StringPayload(data, headers=headers, content_type='application/x-www-form-urlencoded')) @property def size(self) -> Optional[int]: """Size of the payload.""" if not self._parts: return 0 total = 0 for part, encoding, te_encoding in self._parts: if encoding or te_encoding or part.size is None: return None total += int( 2 + len(self._boundary) + 2 + # b'--'+self._boundary+b'\r\n' part.size + len(part._binary_headers) + 2 # b'\r\n' ) total += 2 + len(self._boundary) + 4 # b'--'+self._boundary+b'--\r\n' return total async def write(self, writer: Any, close_boundary: bool=True) -> None: """Write body.""" if not self._parts: return for part, encoding, te_encoding in self._parts: await writer.write(b'--' + self._boundary + b'\r\n') await writer.write(part._binary_headers) if encoding or te_encoding: w = MultipartPayloadWriter(writer) if encoding: w.enable_compression(encoding) if te_encoding: w.enable_encoding(te_encoding) await part.write(w) # type: ignore await w.write_eof() else: await part.write(writer) await writer.write(b'\r\n') if close_boundary: await writer.write(b'--' + self._boundary + b'--\r\n') class MultipartPayloadWriter: def __init__(self, writer: Any) -> None: self._writer = writer self._encoding = None # type: Optional[str] self._compress = None # type: Any self._encoding_buffer = None # type: Optional[bytearray] def enable_encoding(self, encoding: str) -> None: if encoding == 'base64': self._encoding = encoding self._encoding_buffer = bytearray() elif encoding == 'quoted-printable': self._encoding = 'quoted-printable' def enable_compression(self, encoding: str='deflate') -> None: zlib_mode = (16 + zlib.MAX_WBITS if encoding == 'gzip' else -zlib.MAX_WBITS) self._compress = zlib.compressobj(wbits=zlib_mode) async def write_eof(self) -> None: if self._compress is not None: chunk = self._compress.flush() if chunk: self._compress = None await self.write(chunk) if self._encoding == 'base64': if self._encoding_buffer: await self._writer.write(base64.b64encode( self._encoding_buffer)) async def write(self, chunk: bytes) -> None: if self._compress is not None: if chunk: chunk = self._compress.compress(chunk) if not chunk: return if self._encoding == 'base64': buf = self._encoding_buffer assert buf is not None buf.extend(chunk) if buf: div, mod = divmod(len(buf), 3) enc_chunk, self._encoding_buffer = ( buf[:div * 3], buf[div * 3:]) if enc_chunk: b64chunk = base64.b64encode(enc_chunk) await self._writer.write(b64chunk) elif self._encoding == 'quoted-printable': await self._writer.write(binascii.b2a_qp(chunk)) else: await self._writer.write(chunk)