Check whether YouTube channel is live streaming.

check_youtube.py

#!/usr/bin/env python3
# coding: utf-8

import re
import sys
import json
import requests
from retrying import retry

headers = {
    'Accept-Language': 'en-US,en;q=0.8',
    'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:67.0) Gecko/20100101 Firefox/67.0',
}

# Apply for a YouTube Data API v3 key here
# https://console.developers.google.com/apis/library/youtube.googleapis.com
api_key = ''


@retry(stop_max_attempt_number=3)
def get(url: str) -> str:
    try:
        r = requests.get(url, headers=headers)
        return r.text
    except requests.RequestException:
        pass


def get_json(url: str) -> dict:
    try:
        return json.loads(get(url))
    except json.decoder.JSONDecodeError:
        pass


def get_video_info(video_id) -> dict:
    """
    Returns dict of video info.
    YouTube API doc: https://developers.google.com/youtube/v3/docs/videos/list
    """
    try:
        response = get_json(
            f'https://www.googleapis.com/youtube/v3/videos?id={video_id}&'
            f'key={api_key}&part=liveStreamingDetails,snippet'
        )
        item = response['items'][0]
        return item
    except Exception:
        pass


def get_live_video_info_by_channel_id(channel_id: str) -> dict:
    """
    Get current live video of given channel.
    Returns dict of video info with keys:
    { id, title, description, publishedAt, thumbnails, channelId, channelTitle, liveBroadcastContent, }
    YouTube API doc: https://developers.google.com/youtube/v3/docs/search/list
    """
    try:
        response = get_json(
            f'https://www.googleapis.com/youtube/v3/search?part=snippet&'
            f'channelId={channel_id}&eventType=live&maxResults=1&type=video&key={api_key}'
        )
        video_id = response['items'][0]['id']['videoId']
        # The video info in the API response is not complete,
        # so we request the video info with another API here.
        video_info = get_video_info(video_id)
    except Exception:
        raise

    return {
        'id': video_id,
        **video_info['snippet']
    }

def get_live_video_info_from_html(html: str) -> dict:
    """
    Extract video info from HTML of channel page.
    """
    # regex = r'{"itemSectionRenderer":{"contents":\[{"shelfRenderer":{"title":{"runs":\[{"text":"Live now".+?"content":{"expandedShelfContentsRenderer":{"items":(.+?),"showMoreText":{"runs":\[{"text":"Show more"}]}}}'
    regex = r'"contents":\[{"channelFeaturedContentRenderer":{"items":(.+?)}}],"trackingParams"'
    json_items = json.loads(re.search(regex, html).group(1))
    extract = json_items[0]['videoRenderer']

    # print(json.dumps(json_items, indent=2, separators=(',', ': ')))
    # exit(0)

    if (extract['badges'][0]['metadataBadgeRenderer']['label'] != 'LIVE NOW'):
        raise RuntimeError('Not live')

    return {
        'id': extract['videoId'],
        'title': extract['title']['simpleText'],
        'description': extract['descriptionSnippet']['simpleText']
    }

def check_channel_live_streaming(channel_id: str) -> bool:
    try:
        html = get(f'https://www.youtube.com/channel/{channel_id}/featured')
        if '"label":"LIVE NOW"' in html:
            # video_info = get_live_video_info_by_channel_id(channel_id)
            video_info = get_live_video_info_from_html(html)
            return video_info
        else:
            return False
    except Exception:
        raise


# usage: ./check_youtube.py youtube_channel_id
if __name__ == '__main__':
    if (len(sys.argv) < 2):
        print('usage: ' + sys.argv[0] + ' youtube_channel_id', file=sys.stderr)
        exit(1)

    channel_id = sys.argv[1]

    info = check_channel_live_streaming(channel_id)

    if info:
        # Same output format as
        # youtube-dl --get-id --get-title --get-description
        print(info['title'])
        print(info['id'])
        print(info['description'])
    else:
        print(f'No live streams for channel {channel_id} available now', file=sys.stderr)
        exit(1)