th fs.open_upload_stream_with_id( ObjectId(), "test_file", chunk_size_bytes=4, metadata={"contentType": "text/plain"}) as grid_in: grid_in.write("data I want to store!") # uploaded on close Returns an instance of :class:`~gridfs.grid_file.GridIn`. Raises :exc:`~gridfs.errors.NoFile` if no such version of that file exists. Raises :exc:`~ValueError` if `filename` is not a string. :Parameters: - `file_id`: The id to use for this file. The id must not have already been used for another file. - `filename`: The name of the file to upload. - `chunk_size_bytes` (options): The number of bytes per chunk of this file. Defaults to the chunk_size_bytes in :class:`GridFSBucket`. - `metadata` (optional): User data for the 'metadata' field of the files collection document. If not provided the metadata field will be omitted from the files collection document. - `session` (optional): a :class:`~pymongo.client_session.ClientSession` .. versionchanged:: 3.6 Added ``session`` parameter. rD