> For the complete documentation index, see [llms.txt](https://docs.avoautomation.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.avoautomation.com/avo-assure/actions/apis/assertion/header-exists.md).

# Header exists

This is a pre-built action available under **@Assertion** element type. This Action checks whether a specific header name is available in the API response. The output variable stores the validation result as **True** or **False**.

## Syntax

**Input Value**: `<HeaderKey1>,<HeaderKey2(Optional)>,....,<HeaderKeyn(Optional)>`&#x20;

| Argument                                                           | Description                                                                                                                                                                                |
| ------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| \<HeaderKey1>,\<HeaderKey2(Optional)>,....,\<HeaderKeyn(Optional)> | <p>Enter the exact name of the response header that you want to check. </p><p><br><strong>Note</strong>: You can also provide multiple response headers by separating with comma (,). </p> |

**Output Value**: `<Keyword Status(optional)>`

| Argument                     | Description                                                                         |
| ---------------------------- | ----------------------------------------------------------------------------------- |
| \<Keyword Status> (Optional) | The action status variable stores the result of the check as **True** or **False**. |

### **Example: Checking Whether a Header Exists**

In this example, we explain how to verify that the Content-Type header is present in the API response.

* **Action**: Header exists
* **Input Value**: Content-Type
  * The input value **Content-Type** specifies the name of the response header to check.

API Response Headers:

Content-Type: application/json \
Content-Length: 245 \
Cache-Control: no-cache \
StatusCode: 200

* **Output Value**: {Status}
  * The output variable **{Status}** stores the result with the following possible values:
    * **True**: The specified header is available in the API response.
    * **False**: The specified header is not present in the API response.
* **Logical Explanation**: The **Header exists** action takes the header name **Content-Type** from the **Input Value** column and checks whether the header is present in the API response. The action does not check the header value. Since the **Content-Type** header is available, the **{Status}** variable stores **True**.

![](https://2174257472-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fk8QZzXZMIJSStKAzDSTu%2Fuploads%2FXKzlOIw03zySCsD1ONAD%2Funknown.png?alt=media\&token=c5d81c7f-305b-409c-8b3e-cd43901755ec)

### **Example 2: Checking Multiple Headers**

In this example, we explain how to verify that multiple response headers are present in the API response.

* **Action**: Header exists
* **Input Value**: Content-Type,Authorization,Cache-Control
* The input values **Content-Type**, **Authorization**, and **Cache-Control** specify the names of the response headers to check. Each header name is separated by a comma.

API Response Headers

Content-Type: application/json \
Authorization: Bearer token123 \
Cache-Control: no-cache \
StatusCode: 200&#x20;

* **Output Value:** {Status}
  * The output variable **{Status}** stores the result with the following possible values:
    * **True**: All the specified headers are present in the API response.
    * **False**: One or more of the specified headers are not present in the API response.
* **Logical Explanation:** The **Header exists** action takes the multiple header names **Content-Type**, **Authorization**, and **Cache-Control** from the **Input Value** column and checks whether each header is present in the API response. The action does not check the values of the headers. Since all the specified headers are available in the API response, the **{Status}** variable stores **True**.

![](https://2174257472-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fk8QZzXZMIJSStKAzDSTu%2Fuploads%2F94OKrVZdv8Y0zlJ49JeY%2Funknown.png?alt=media\&token=35aab3c2-4c5d-42f5-abdf-be374359209f)


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