# Read and update control nodes

This example explains how to use composition scripting to read and update a composition's control nodes.

### Functions covered

* `comp.find()`
* `comp.getPayload()`
* `comp.getPayload2()`
* `comp.setPayload()`

Load this [example composition](https://app.singular.live/dashboard?templateLibraryItem=546) to follow along in a real composition.

### **Composition structure**

The example composition has one sub-composition called **Lower**, as you can see in the composition tree.

To see the sub-composition's objects:

* Select the Lower sub-composition and **Control Properties** in the property panel.

<figure><img src="https://lh3.googleusercontent.com/Lg_kWIXGrlXEvUy1qbOz1guO5uTFWizduI7zZh5xSFtZYkE79am8dOFOHDaGjHv-gt9zt2QBrdn6zeCpbiQx2qVXI1TOItOzv05AplparhYjEtBF-k8UnHRcvGIdGQ1Mfkt3M9PEMYtcrQYTHkjShhazrjQxz0nkRbmM-PCml4LnErcOh83zHw5T7KDT9g" alt=""><figcaption><p>The Lower sub-composition</p></figcaption></figure>

To see this sub-composition's control nodes:

1. [Open the composition script editor](/composition-scripting/composition-script-editor-reference.md#accessing-the-composition-script-editor) within the same [example composition](https://app.singular.live/compositions/458659/edit) as above and open the **Lower composition script.**
2. In the Composition Control tab, select **Lower** and then the **Sub-comp info** tab.

This composition contains three control nodes:

* Title: a **text** control node
* Subtitle: a **textarea** control node
* Station Logo: an **image** control node

<figure><img src="https://lh5.googleusercontent.com/iaTgtG9Q9UVDJ_YW8RX_DvVJ84yMf_nWSMwLBDJpQgK_s62mKeZ25KdPVwcfaolVZ9xFUSAyMCmhbEqLDwjtdlO_eh3nKlu915DH5rCu0JhDzhHH8D6MDnL94LM5pN1MvUOiDxMSgublKiZY75gxOJ0qxQJenmbDlQduxDFLMHyxiPGXFKeg5Rmq1TKMHg" alt=""><figcaption><p>The sub-composition's control nodes</p></figcaption></figure>

### Composition script

Now that you have located the composition's control nodes, learn how to read and update them by reading the comments in the Lower composition script.&#x20;

You can also copy and paste the composition script below into your own compositions.&#x20;

{% code title="Lower Script" %}

```javascript
(function() {
  return {

    init: function(comp, context) {

      // get control node payload as array of key-value pairs
      const payload = comp.getPayload();
      console.log(payload);

      // get control node payload as JSON object
      const payload2 = comp.getPayload2();
      console.log(payload2);

      // set new control node payload
      const newPayload = {
        "Title": "New title",
        "Subtitle": "New subtitle line 1\nNew subtitle line 2",
        "Station Logo": "https://github.githubassets.com/images/modules/logos_page/GitHub-Mark.png"
      };
      comp.setPayload(newPayload);

    },

    close: function(comp, context) {}
  };
})();
```

{% endcode %}


---

# Agent Instructions: 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:

```
GET https://developer.singular.live/composition-scripting/quick-start/read-and-update-control-nodes.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
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.