publisher/platforms/base.py

import os

def validate_payload(payload):

    if "video_path" not in payload:
        raise Exception("video_path required")

    if not os.path.exists(payload["video_path"]):
        raise Exception("Video missing")

    payload.setdefault("caption", "")
    payload.setdefault("hashtags", [])
    payload.setdefault("thumbnail", None)

    return payload