/**
 * Saves a file (encoded as base64) into this service.
 *
 * Technical:
 * POST to /internal/media/upload/ with JSON payload.
 * Returns 200 on success, 4xx on Errors with a message in the payload.
 */
upload(file: string, id: Id, mimetype: string): {message: string} | void

/**
 * Retrieves a mediafile given by the meeting and the path of the file.
 *
 * Technical:
 * GET to /system/media/get/<meeting_id>/<path>
 */
get(meeting_id: Id, path: string): Blob