Quickstart

This page takes you from nothing to a question appearing on a viewer’s screen.

You will need an AntCDN API key scoped to an environment, and an encoder such as OBS.

1. Create an interactive live stream

Set interactive to true when you create the stream. This cannot be added later, so set it now even if you are not sure you will use it.

curl -X POST https://api.antcdn.net/v1/live-streams \
  -H "X-Api-Key: $ANTCDN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
        "name": "Launch stream",
        "interactive": true,
        "recording": true
      }'

The response includes your streamId, the RTMP ingest URL and your stream key.

2. Start broadcasting

Point your encoder at the RTMP URL and stream key from step 1. See Encoder setup for settings.

Wait until the stream is live. Questions can only be asked while a stream is broadcasting, because a question needs a point in the broadcast to belong to.

3. Ask a question

curl -X POST https://api.antcdn.net/v1/live-streams/$STREAM_ID/questions \
  -H "X-Api-Key: $ANTCDN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
        "prompt": "Which build should we ship first?",
        "options": ["The rewrite", "The patch"],
        "allowFreeText": false
      }'

You get back the question id and the offset in seconds from the start of the broadcast:

{
  "questionId": "lsq_71c4a9",
  "offsetSeconds": 412
}

The question is now written into your video. Viewers see it when their playback reaches this point.

4. Show it to viewers

The fastest way is the hosted player. Add interactive=1 to the embed URL and the player draws the question overlay for you:

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<iframe
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  src="https://player.antcdn.net/v1/{edgeId}/master.m3u8?interactive=1"
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  allow="autoplay; fullscreen"
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  frameborder="0"
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></iframe>

edgeId is returned when you create the stream. It is the playback id, and it is different from streamId, which is the id you use on the API. You only need the edge id here. The player works out which room to join.

If you are building your own player, install the SDK instead:

npm install @antcdn/live-signaling

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import { connectLiveRoom } from '@antcdn/live-signaling';
2

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const room = connectLiveRoom({ streamId: 'ls_9f2a' });
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room.on('question', (question) => showPoll(question));
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room.on('tally', (tally) => updateResults(tally));
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room.on('closed', (tally) => showFinalResult(tally));

See Player SDK for the full guide, including how to tell the SDK when playback reaches a question.

5. Close the question

Closing stops the voting and returns the final numbers.

curl -X POST \
  https://api.antcdn.net/v1/live-streams/$STREAM_ID/questions/$QUESTION_ID/close \
  -H "X-Api-Key: $ANTCDN_API_KEY"

{
  "questionId": "lsq_71c4a9",
  "counts": [1204, 388],
  "total": 1592
}

counts lines up with the options array you sent. Index 0 is the first option.

The result is stored, so you can read it back later from the timeline.

What next

• Let viewers write answers in their own words: set allowFreeText to true and read them back with the responses endpoint.
• Keep the questions working on the recording: see Recordings.