> ## Documentation Index
> Fetch the complete documentation index at: https://docs.clearline.me/llms.txt
> Use this file to discover all available pages before exploring further.

# Client Credentials Grant Authorization (POS Authorization)

Client Credentials Grant Authorization (POS Authorization)

### OAuth 2.0 – Client Credentials Grant (with Basic Auth)

This authorization flow is intended for **Point-of-Sale (POS)** systems that need to securely authenticate with our platform using **OAuth 2.0 Client Credentials Grant**.

In this flow, the POS system (i.e., the client) authenticates itself directly using a **client ID** and **client secret**, which are provided to you during the integration setup process.

***

## 📘 Credentials

To authorize your POS system, you will receive:

* `client_id`: The unique identifier for your POS integration
* `client_secret`: A secure secret key associated with the client ID

⚠️ **Important:**<br />
Your `client_secret` is sensitive and must be kept confidential. Never expose it in client-side applications or public repositories.

***

## 🔄 Token Request

To obtain an access token, make a `POST` request to the token endpoint using **HTTP Basic Authentication**.

### 📤 Request

**Endpoint:**

`POST https://logintest.clearline.me/connect/token`

**Headers:**

`Content-Type: application/x-www-form-urlencoded`

`Authorization: Basic {Base64(client_id:client_secret)}`

* Replace `{Base64(client_id:client_secret)}` with the base64-encoded value of your credentials.
  * For example, if:
    * `client_id = pos-demo`
    * `client_secret = s3cr3t!`

Then:

`Authorization: Basic cG9zLWRlbW86czNjcjN0IQ==`

*

**Body Parameters:**

`grant_type=client_credentials`

`scope=pos_integration`

### ✅ Example Request (curl)

`curl -X POST https://logintest.clearline.me/connect/token \`

`  -H "Content-Type: application/x-www-form-urlencoded" \`

`  -H "Authorization: Basic cG9zLWRlbW86czNjcjN0IQ==" \`

`  -d "grant_type=client_credentials&scope=pos_integration"`

***

## 🎯 Successful Response

If your credentials are valid, the response will contain an access token:

`{`

`  "access_token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...",`

`  "token_type": "Bearer",`

`  "expires_in": 3600,`

`  "scope": "pos_integration"`

`}`

* `access_token`: This token must be included in subsequent API requests
* `token_type`: Always `Bearer`
* `expires_in`: Lifetime of the token in seconds (typically 3600)

***

## 🔐 Using the Access Token

Include the access token in the `Authorization` header when making authenticated requests to POS-protected APIs.

**Example:**

`Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9...`