[[_service_authorization_aat]]
==== What is an AAT and How to Obtain It

An authorization API token (AAT) is a special OAuth2 access token with the scope *uma_authorization*. When you create a user, {{book.project.name}} automatically
assigns the role _uma_authorization_ to the user. The _uma_authorization_ role is a default realm role.

.Default Role uma_authorization
image:../../../images/service/rs-uma-authorization-role.png[alt="Default Role uma_authorization "]

An AAT enables a client application to query the server for user permissions.

Client applications can obtain an AAT from {{book.project.name}} like any other OAuth2 access token. Usually, client applications obtain AATs after the user is successfully
authenticated in {{book.project.name}}. By default, the _authorization_code_ grant type is used to authenticate users, and the server will issue an OAuth2 access token to the client application acting on their behalf.

The example below uses the Resource Owner Password Credentials Grant Type to request an AAT:

```bash
curl -X POST \
    -H "Authorization: Basic aGVsbG8td29ybGQtYXV0aHotc2VydmljZTpwYXNzd29yZA==" \
    -H "Content-Type: application/x-www-form-urlencoded" \
    -d 'username=${username}&password=${user_password}&grant_type=password' \
    "http://localhost:8080/auth/realms/${realm_name}/protocol/openid-connect/token"
```

As a result, the server response is:

```json
{
  "access_token": ${AAT},
  "expires_in": 300,
  "refresh_expires_in": 1800,
  "refresh_token": ${refresh_token},
  "token_type": "bearer",
  "id_token": ${id_token},
  "not-before-policy": 0,
  "session_state": "3cad2afc-855b-47b7-8e4d-a21c66e312fb"
}
```