jpayne@7: from __future__ import annotations
jpayne@7: 
jpayne@7: import binascii
jpayne@7: import codecs
jpayne@7: import os
jpayne@7: import typing
jpayne@7: from io import BytesIO
jpayne@7: 
jpayne@7: from .fields import _TYPE_FIELD_VALUE_TUPLE, RequestField
jpayne@7: 
jpayne@7: writer = codecs.lookup("utf-8")[3]
jpayne@7: 
jpayne@7: _TYPE_FIELDS_SEQUENCE = typing.Sequence[
jpayne@7:     typing.Union[typing.Tuple[str, _TYPE_FIELD_VALUE_TUPLE], RequestField]
jpayne@7: ]
jpayne@7: _TYPE_FIELDS = typing.Union[
jpayne@7:     _TYPE_FIELDS_SEQUENCE,
jpayne@7:     typing.Mapping[str, _TYPE_FIELD_VALUE_TUPLE],
jpayne@7: ]
jpayne@7: 
jpayne@7: 
jpayne@7: def choose_boundary() -> str:
jpayne@7:     """
jpayne@7:     Our embarrassingly-simple replacement for mimetools.choose_boundary.
jpayne@7:     """
jpayne@7:     return binascii.hexlify(os.urandom(16)).decode()
jpayne@7: 
jpayne@7: 
jpayne@7: def iter_field_objects(fields: _TYPE_FIELDS) -> typing.Iterable[RequestField]:
jpayne@7:     """
jpayne@7:     Iterate over fields.
jpayne@7: 
jpayne@7:     Supports list of (k, v) tuples and dicts, and lists of
jpayne@7:     :class:`~urllib3.fields.RequestField`.
jpayne@7: 
jpayne@7:     """
jpayne@7:     iterable: typing.Iterable[RequestField | tuple[str, _TYPE_FIELD_VALUE_TUPLE]]
jpayne@7: 
jpayne@7:     if isinstance(fields, typing.Mapping):
jpayne@7:         iterable = fields.items()
jpayne@7:     else:
jpayne@7:         iterable = fields
jpayne@7: 
jpayne@7:     for field in iterable:
jpayne@7:         if isinstance(field, RequestField):
jpayne@7:             yield field
jpayne@7:         else:
jpayne@7:             yield RequestField.from_tuples(*field)
jpayne@7: 
jpayne@7: 
jpayne@7: def encode_multipart_formdata(
jpayne@7:     fields: _TYPE_FIELDS, boundary: str | None = None
jpayne@7: ) -> tuple[bytes, str]:
jpayne@7:     """
jpayne@7:     Encode a dictionary of ``fields`` using the multipart/form-data MIME format.
jpayne@7: 
jpayne@7:     :param fields:
jpayne@7:         Dictionary of fields or list of (key, :class:`~urllib3.fields.RequestField`).
jpayne@7:         Values are processed by :func:`urllib3.fields.RequestField.from_tuples`.
jpayne@7: 
jpayne@7:     :param boundary:
jpayne@7:         If not specified, then a random boundary will be generated using
jpayne@7:         :func:`urllib3.filepost.choose_boundary`.
jpayne@7:     """
jpayne@7:     body = BytesIO()
jpayne@7:     if boundary is None:
jpayne@7:         boundary = choose_boundary()
jpayne@7: 
jpayne@7:     for field in iter_field_objects(fields):
jpayne@7:         body.write(f"--{boundary}\r\n".encode("latin-1"))
jpayne@7: 
jpayne@7:         writer(body).write(field.render_headers())
jpayne@7:         data = field.data
jpayne@7: 
jpayne@7:         if isinstance(data, int):
jpayne@7:             data = str(data)  # Backwards compatibility
jpayne@7: 
jpayne@7:         if isinstance(data, str):
jpayne@7:             writer(body).write(data)
jpayne@7:         else:
jpayne@7:             body.write(data)
jpayne@7: 
jpayne@7:         body.write(b"\r\n")
jpayne@7: 
jpayne@7:     body.write(f"--{boundary}--\r\n".encode("latin-1"))
jpayne@7: 
jpayne@7:     content_type = f"multipart/form-data; boundary={boundary}"
jpayne@7: 
jpayne@7:     return body.getvalue(), content_type