Source code for aiohttp.multipart

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 (
    TYPE_CHECKING,
    Any,
    AsyncIterator,
    Deque,
    Dict,
    Iterator,
    List,
    Mapping,
    Optional,
    Sequence,
    Tuple,
    Type,
    Union,
    cast,
)
from urllib.parse import parse_qsl, unquote, urlencode

from multidict import CIMultiDict, CIMultiDictProxy, MultiMapping

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


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(f"\\\\([{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 = f"{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 MultipartReader.

    It takes care about
    underlying connection and close it when it needs in.
    """

    def __init__(
        self,
        resp: "ClientResponse",
        stream: "MultipartReader",
    ) -> None:
        self.resp = resp
        self.stream = stream

    def __aiter__(self) -> "MultipartResponseWrapper":
        return self

    async def __anext__(
        self,
    ) -> Union["MultipartReader", "BodyPartReader"]:
        part = await self.next()
        if part is None:
            raise StopAsyncIteration
        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,
    ) -> Optional[Union["MultipartReader", "BodyPartReader"]]:
        """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:
        """Release the connection gracefully.

        All remaining content is read to the void.
        """
        await self.resp.release()


[docs]class BodyPartReader: """Multipart reader for single body part.""" chunk_size = 8192 def __init__( self, boundary: bytes, headers: "CIMultiDictProxy[str]", content: StreamReader, *, _newline: bytes = b"\r\n", ) -> None: self.headers = headers self._boundary = boundary self._newline = _newline 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[bytes] = deque() self._prev_chunk = None # type: Optional[bytes] self._content_eof = 0 self._cache = {} # type: Dict[str, Any] def __aiter__(self) -> AsyncIterator["BodyPartReader"]: return self # type: ignore[return-value] async def __anext__(self) -> bytes: part = await self.next() if part is None: raise StopAsyncIteration return part async def next(self) -> Optional[bytes]: item = await self.read() if not item: return None return item
[docs] async def read(self, *, decode: bool = False) -> bytes: """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
[docs] 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) # For the case of base64 data, we must read a fragment of size with a # remainder of 0 by dividing by 4 for string without symbols \n or \r encoding = self.headers.get(CONTENT_TRANSFER_ENCODING) if encoding and encoding.lower() == "base64": stripped_chunk = b"".join(chunk.split()) remainder = len(stripped_chunk) % 4 while remainder != 0 and not self.at_eof(): over_chunk_size = 4 - remainder over_chunk = b"" if self._prev_chunk: over_chunk = self._prev_chunk[:over_chunk_size] self._prev_chunk = self._prev_chunk[len(over_chunk) :] if len(over_chunk) != over_chunk_size: over_chunk += await self._content.read(4 - len(over_chunk)) if not over_chunk: self._at_eof = True stripped_chunk += b"".join(over_chunk.split()) chunk += over_chunk remainder = len(stripped_chunk) % 4 self._read_bytes += len(chunk) if self._read_bytes == self._length: self._at_eof = True if self._at_eof: newline = await self._content.readline() assert ( newline == self._newline ), "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 intermeditate_boundary = self._newline + self._boundary if first_chunk: pos = 0 else: pos = max(0, len(self._prev_chunk) - len(intermeditate_boundary)) idx = window.find(intermeditate_boundary, pos) 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
[docs] 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): # strip newline but only once line = line[: -len(self._newline)] self._unread.append(next_line) return line
[docs] 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)
[docs] 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)
[docs] async def json(self, *, encoding: Optional[str] = None) -> Optional[Dict[str, 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 cast(Dict[str, Any], json.loads(data.decode(encoding)))
[docs] async def form(self, *, encoding: Optional[str] = None) -> List[Tuple[str, str]]: """Like read(), but assumes that body parts contain 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, )
[docs] def at_eof(self) -> bool: """Returns True if the boundary was reached or False otherwise.""" return self._at_eof
[docs] def decode(self, data: bytes) -> bytes: """Decodes data. Decoding is done 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 = self.headers.get(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(f"unknown content encoding: {encoding}") def _decode_content_transfer(self, data: bytes) -> bytes: encoding = self.headers.get(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) )
[docs] 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. If the header is missing or malformed, returns None. """ _, 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. Returns None if the header is missing or 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)
[docs]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, *, _newline: bytes = b"\r\n", ) -> None: self.headers = headers self._boundary = ("--" + self._get_boundary()).encode() self._newline = _newline self._content = content self._last_part = ( None ) # type: Optional[Union['MultipartReader', BodyPartReader]] self._at_eof = False self._at_bof = True self._unread = [] # type: List[bytes] def __aiter__( self, ) -> AsyncIterator["BodyPartReader"]: return self # type: ignore[return-value] async def __anext__( self, ) -> Optional[Union["MultipartReader", BodyPartReader]]: part = await self.next() if part is None: raise StopAsyncIteration return part
[docs] @classmethod def from_response( cls, response: "ClientResponse", ) -> MultipartResponseWrapper: """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
[docs] def at_eof(self) -> bool: """Returns True if the final boundary was reached, false otherwise.""" return self._at_eof
[docs] async def next( self, ) -> Optional[Union["MultipartReader", BodyPartReader]]: """Emits the next multipart body part.""" # So, if we're at BOF, we need to skip till the boundary. if self._at_eof: return None 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 None self._last_part = await self.fetch_next_part() return self._last_part
[docs] 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()
[docs] async def fetch_next_part( self, ) -> Union["MultipartReader", BodyPartReader]: """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]", ) -> Union["MultipartReader", BodyPartReader]: """Dispatches the response by the `Content-Type` header. Returns a 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, _newline=self._newline ) else: return self.part_reader_cls( self._boundary, headers, self._content, _newline=self._newline ) 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) ) newline = None end_boundary = self._boundary + b"--" if chunk.startswith(end_boundary): _, newline = chunk.split(end_boundary, 1) elif chunk.startswith(self._boundary): _, newline = chunk.split(self._boundary, 1) if newline is not None: assert newline in (b"\r\n", b"\n"), (newline, chunk, self._boundary) self._newline = newline chunk = chunk.rstrip() if chunk == self._boundary: return elif chunk == end_boundary: 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(f"Invalid boundary {chunk!r}, expected {self._boundary!r}") 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]
[docs]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 if len(boundary) > 70: raise ValueError("boundary %r is too long (70 chars max)" % boundary) ctype = f"multipart/{subtype}; boundary={self._boundary_value}" super().__init__(None, content_type=ctype) self._parts = [] # type: List[_Part] 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) def __bool__(self) -> bool: return True _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")
[docs] 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)
[docs] 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] if encoding and encoding not in ("deflate", "gzip", "identity"): raise RuntimeError(f"unknown content encoding: {encoding}") if encoding == "identity": encoding = None # te encoding te_encoding = payload.headers.get( CONTENT_TRANSFER_ENCODING, "", ).lower() # type: Optional[str] 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[arg-type] return payload
[docs] 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))
[docs] 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.""" 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 + part.size # b'--'+self._boundary+b'\r\n' + len(part._binary_headers) + 2 # b'\r\n' ) total += 2 + len(self._boundary) + 4 # b'--'+self._boundary+b'--\r\n' return total
[docs] async def write(self, writer: Any, close_boundary: bool = True) -> None: """Write body.""" 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[arg-type] 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", strategy: int = zlib.Z_DEFAULT_STRATEGY ) -> None: zlib_mode = 16 + zlib.MAX_WBITS if encoding == "gzip" else -zlib.MAX_WBITS self._compress = zlib.compressobj(wbits=zlib_mode, strategy=strategy) 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)