> For the complete documentation index, see [llms.txt](https://developer.singular.live/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.singular.live/data-stream-api/how-to-guides/link-a-data-stream-to-a-composition.md).

# Link a data stream to a composition

{% hint style="info" %}
This how-to guide requires composition scripting to prepare the composition to accept data from the data stream API. For an overview of composition scripting and to learn how to accomplish common tasks with it, visit the [composition scripting](/composition-scripting/introduction.md) section of this portal. 
{% endhint %}

1. Open the composition you want to connect to a data stream in Composer.
2. If you haven't already created a control node for the widget you want to update with the data stream API, [create a control node](/singular-basics/building-overlays-in-composer/how-to-set-up-control-nodes-to-make-widget-properties-available-to-a-control-app.md) for it.
3. Open the [composition script editor](/singular-basics/building-overlays-in-composer/composer-reference.md#areas-of-the-property-panel) and paste this code snippet into it. You'll need to connect it to the control node in strep 2 and also add the public data stream token.

{% code title="Composition Script" %}

```javascript
context.utils.createDataStream(
  data_stream_public_token, 
  (status, payload) => 
  {
    console.log("we have received: ", status, payload);
    if (status === "message") {
      	// process your data here
    }
  });
```

{% endcode %}

{% hint style="info" %}
For more help, see the composition scripting section of this portal.
{% endhint %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://developer.singular.live/data-stream-api/how-to-guides/link-a-data-stream-to-a-composition.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.