Modern Python Standard Library Cookbook

How to do it...

Here are the steps for this recipe:

1. multipart itself requires tracking all the fields and files we want to encode and then performing the encoding itself.
2. We will rely on io.BytesIO to store all the resulting bytes:

import io import mimetypes import uuid class MultiPartForm: def __init__(self): self.fields = {} self.files = [] def __setitem__(self, name, value): self.fields[name] = value def add_file(self, field, filename, data, mimetype=None): if mimetype is None: mimetype = (mimetypes.guess_type(filename)[0] or 'application/octet-stream') self.files.append((field, filename, mimetype, data)) def _generate_bytes(self, boundary): buffer = io.BytesIO() for field, value in self.fields.items(): buffer.write(b'--' + boundary ...