jpayne@69: from __future__ import annotations
jpayne@69: 
jpayne@69: import binascii
jpayne@69: import codecs
jpayne@69: import os
jpayne@69: import typing
jpayne@69: from io import BytesIO
jpayne@69: 
jpayne@69: from .fields import _TYPE_FIELD_VALUE_TUPLE, RequestField
jpayne@69: 
jpayne@69: writer = codecs.lookup("utf-8")[3]
jpayne@69: 
jpayne@69: _TYPE_FIELDS_SEQUENCE = typing.Sequence[
jpayne@69:     typing.Union[typing.Tuple[str, _TYPE_FIELD_VALUE_TUPLE], RequestField]
jpayne@69: ]
jpayne@69: _TYPE_FIELDS = typing.Union[
jpayne@69:     _TYPE_FIELDS_SEQUENCE,
jpayne@69:     typing.Mapping[str, _TYPE_FIELD_VALUE_TUPLE],
jpayne@69: ]
jpayne@69: 
jpayne@69: 
jpayne@69: def choose_boundary() -> str:
jpayne@69:     """
jpayne@69:     Our embarrassingly-simple replacement for mimetools.choose_boundary.
jpayne@69:     """
jpayne@69:     return binascii.hexlify(os.urandom(16)).decode()
jpayne@69: 
jpayne@69: 
jpayne@69: def iter_field_objects(fields: _TYPE_FIELDS) -> typing.Iterable[RequestField]:
jpayne@69:     """
jpayne@69:     Iterate over fields.
jpayne@69: 
jpayne@69:     Supports list of (k, v) tuples and dicts, and lists of
jpayne@69:     :class:`~urllib3.fields.RequestField`.
jpayne@69: 
jpayne@69:     """
jpayne@69:     iterable: typing.Iterable[RequestField | tuple[str, _TYPE_FIELD_VALUE_TUPLE]]
jpayne@69: 
jpayne@69:     if isinstance(fields, typing.Mapping):
jpayne@69:         iterable = fields.items()
jpayne@69:     else:
jpayne@69:         iterable = fields
jpayne@69: 
jpayne@69:     for field in iterable:
jpayne@69:         if isinstance(field, RequestField):
jpayne@69:             yield field
jpayne@69:         else:
jpayne@69:             yield RequestField.from_tuples(*field)
jpayne@69: 
jpayne@69: 
jpayne@69: def encode_multipart_formdata(
jpayne@69:     fields: _TYPE_FIELDS, boundary: str | None = None
jpayne@69: ) -> tuple[bytes, str]:
jpayne@69:     """
jpayne@69:     Encode a dictionary of ``fields`` using the multipart/form-data MIME format.
jpayne@69: 
jpayne@69:     :param fields:
jpayne@69:         Dictionary of fields or list of (key, :class:`~urllib3.fields.RequestField`).
jpayne@69:         Values are processed by :func:`urllib3.fields.RequestField.from_tuples`.
jpayne@69: 
jpayne@69:     :param boundary:
jpayne@69:         If not specified, then a random boundary will be generated using
jpayne@69:         :func:`urllib3.filepost.choose_boundary`.
jpayne@69:     """
jpayne@69:     body = BytesIO()
jpayne@69:     if boundary is None:
jpayne@69:         boundary = choose_boundary()
jpayne@69: 
jpayne@69:     for field in iter_field_objects(fields):
jpayne@69:         body.write(f"--{boundary}\r\n".encode("latin-1"))
jpayne@69: 
jpayne@69:         writer(body).write(field.render_headers())
jpayne@69:         data = field.data
jpayne@69: 
jpayne@69:         if isinstance(data, int):
jpayne@69:             data = str(data)  # Backwards compatibility
jpayne@69: 
jpayne@69:         if isinstance(data, str):
jpayne@69:             writer(body).write(data)
jpayne@69:         else:
jpayne@69:             body.write(data)
jpayne@69: 
jpayne@69:         body.write(b"\r\n")
jpayne@69: 
jpayne@69:     body.write(f"--{boundary}--\r\n".encode("latin-1"))
jpayne@69: 
jpayne@69:     content_type = f"multipart/form-data; boundary={boundary}"
jpayne@69: 
jpayne@69:     return body.getvalue(), content_type