# Authorization Manager

An Authorization Manager is an instance of the `AuthManager` class that is plugged into one of the Feast servers to extract user details from the current request and inject them into the [permission](../concepts/permission) framework.

{% hint style="info" %}
**Note**: Feast does not provide authentication capabilities; it is the client's responsibility to manage the authentication token and pass it to the Feast server, which then validates the token and extracts user details from the configured authentication server.
{% endhint %}

Two authorization managers are supported out-of-the-box:

* One using a configurable OIDC server to extract the user details.
* One using the Kubernetes RBAC resources to extract the user details.

These instances are created when the Feast servers are initialized, according to the authorization configuration defined in their own `feature_store.yaml`.

Feast servers and clients must have consistent authorization configuration, so that the client proxies can automatically inject the authorization tokens that the server can properly identify and use to enforce permission validations.

## Design notes

The server-side implementation of the authorization functionality is defined [here](https://github.com/feast-dev/feast/blob/v0.52-branch/sdk/python/feast/permissions/server/README.md). Few of the key models, classes to understand the authorization implementation on the client side can be found [here](https://github.com/feast-dev/feast/blob/v0.52-branch/sdk/python/feast/permissions/client/README.md).

## Configuring Authorization

The authorization is configured using a dedicated `auth` section in the `feature_store.yaml` configuration.

**Note**: As a consequence, when deploying the Feast servers with the Helm [charts](https://github.com/feast-dev/feast/blob/v0.52-branch/infra/charts/feast-feature-server/README.md), the `feature_store_yaml_base64` value must include the `auth` section to specify the authorization configuration.

### No Authorization

This configuration applies the default `no_auth` authorization:

```yaml
project: my-project
auth:
  type: no_auth
...
```

### OIDC Authorization

With OIDC authorization, the Feast client proxies retrieve the JWT token from an OIDC server (or [Identity Provider](https://openid.net/developers/how-connect-works/)) and append it in every request to a Feast server, using an [Authorization Bearer Token](https://developer.mozilla.org/en-US/docs/Web/HTTP/Authentication#bearer).

The server, in turn, uses the same OIDC server to validate the token and extract the user roles from the token itself.

Some assumptions are made in the OIDC server configuration:

* The OIDC token refers to a client with roles matching the RBAC roles of the configured `Permission`s (\*)
* The roles are exposed in the access token that is passed to the server
* The JWT token is expected to have a verified signature and not be expired. The Feast OIDC token parser logic validates for `verify_signature` and `verify_exp` so make sure that the given OIDC provider is configured to meet these requirements.
* The preferred\_username should be part of the JWT token claim.

(\*) Please note that **the role match is case-sensitive**, e.g. the name of the role in the OIDC server and in the `Permission` configuration must be exactly the same.

For example, the access token for a client `app` of a user with `reader` role should have the following `resource_access` section:

```json
{
  "resource_access": {
    "app": {
      "roles": [
        "reader"
      ]
    }
  }
}
```

An example of feast OIDC authorization configuration on the server side is the following:

```yaml
project: my-project
auth:
  type: oidc
  client_id: _CLIENT_ID__
  auth_discovery_url: _OIDC_SERVER_URL_/realms/master/.well-known/openid-configuration
...
```

In case of client configuration, the following settings username, password and client\_secret must be added to specify the current user:

```yaml
auth:
  type: oidc
  ...
  username: _USERNAME_
  password: _PASSWORD_
  client_secret: _CLIENT_SECRET__
```

Below is an example of feast full OIDC client auth configuration:

```yaml
project: my-project
auth:
  type: oidc
  client_id: test_client_id
  client_secret: test_client_secret
  username: test_user_name
  password: test_password
  auth_discovery_url: http://localhost:8080/realms/master/.well-known/openid-configuration
```

### Kubernetes RBAC Authorization

With Kubernetes RBAC Authorization, the client uses the service account token as the authorizarion bearer token, and the server fetches the associated roles from the Kubernetes RBAC resources.

An example of Kubernetes RBAC authorization configuration is the following:

{% hint style="info" %}
**NOTE**: This configuration will only work if you deploy feast on Openshift or a Kubernetes platform.
{% endhint %}

\`\`\`yaml project: my-project auth: type: kubernetes ... \`\`\`

In case the client cannot run on the same cluster as the servers, the client token can be injected using the `LOCAL_K8S_TOKEN` environment variable on the client side. The value must refer to the token of a service account created on the servers cluster and linked to the desired RBAC roles.

#### Setting Up Kubernetes RBAC for Feast

To ensure the Kubernetes RBAC environment aligns with Feast's RBAC configuration, follow these guidelines:

* The roles defined in Feast `Permission` instances must have corresponding Kubernetes RBAC `Role` names.
* The Kubernetes RBAC `Role` must reside in the same namespace as the Feast service.
* The client application can run in a different namespace, using its own dedicated `ServiceAccount`.
* Finally, the `RoleBinding` that links the client `ServiceAccount` to the RBAC `Role` must be defined in the namespace of the Feast service.

If the above rules are satisfied, the Feast service must be granted permissions to fetch `RoleBinding` instances from the local namespace.
