zulip/zerver/lib/url_preview/oembed/__init__.py

from typing import Optional, Text, Dict, Any
from pyoembed import oEmbed, PyOembedException


def get_oembed_data(url: Text,
                    maxwidth: Optional[int]=640,
                    maxheight: Optional[int]=480) -> Optional[Dict[Any, Any]]:
    try:
        data = oEmbed(url, maxwidth=maxwidth, maxheight=maxheight)
    except PyOembedException:
        return None

    data['image'] = data.get('thumbnail_url')
    return data