Request body to start a file upload.
| Property | Type | Description |
|---|---|---|
| content_type | String | The MIME type of the file. |
| external_url | String | Public HTTPS URL to import. Required for external_url. |
| filename | String | The filename. Required for multi_part and external_url. |
| mode | String | `single_part` (default), `multi_part` (files over 20 MiB) or `external_url`. |
| number_of_parts | Integer | Number of parts. Required for multi_part (1-10000). |