Auto stream capture not detecting live broadcasts

[Samuel87]

I need help with my Python script that should automatically capture live streams. The script keeps saying the channel is offline even when I can see it’s actually streaming.

import subprocess
import time
import os
import json

channel_name = "example_streamer"
video_quality = "720p"
output_directory = "/home/user/recordings"

if not os.path.exists(output_directory):
    os.makedirs(output_directory)

while True:
    try:
        result = subprocess.check_output(["streamlink", "--json", f"https://www.twitch.tv/{channel_name}", video_quality])
        json_data = json.loads(result.decode("utf-8"))
        video_stream = json_data["streams"][video_quality]["url"]
        timestamp = time.strftime('%Y%m%d_%H%M%S')
        output_file = f"{channel_name}_{timestamp}.mp4"
        full_path = os.path.join(output_directory, output_file)
        print("Found active stream, beginning capture...")
        subprocess.call(["streamlink", video_stream, video_quality, "-o", full_path])
    except:
        print("No active stream found, retrying in 60 seconds...")
        time.sleep(60)

The problem is that it always shows “No active stream found” message and never starts recording. I already tried reinstalling Python and all the packages but nothing changed. What could be wrong with my approach?

[sofiag]

Your subprocess command has the wrong streamlink syntax. When you run subprocess.check_output(["streamlink", "--json", f"https://www.twitch.tv/{channel_name}", video_quality]), streamlink doesn’t return JSON about stream availability - it tries to process the stream and crashes if it’s offline. I ran into this same issue building my capture setup. First check if the stream’s live with subprocess.check_output(["streamlink", "--json", f"https://www.twitch.tv/{channel_name}"]) (drop the quality parameter). Parse that response to see if streams exist, then run your actual recording command. Also double-check that streamlink has the right auth tokens if those streams need them.

[Mia92]

you’re using the wrong streamlink approach. i had the same issues - turns out streamlink --json doesn’t work like you’d expect. skip the subprocess mess and just run streamlink --retry-streams 5 https://twitch.tv/channelname best -o filename.mp4. the --retry-streams flag will automatically check if the stream’s offline and start recording when it goes live.