What Provider should use for the SuperSet which is integrated with Keycloak as an authentication provider?

Question

I have setup a SuperSet with a Keycloak integrated as an authentication provider. In the official API documentation, we can get the access token by calling /security/login API with corresponding credential data provided. The example of the document is using "db" as provider. In my case, I believe I should change this option. However, I have tried to search for the suitable provider name in my scenario but no luck (i.g. ido,idoc,none of them works..)...

Does anyone know what provider name should I put in this case?

POST ​/security​/login
Request body
{
  "password": "complex-password",
  "provider": "db",
  "refresh": true,
  "username": "admin"
}