---
title: Expression Policies
---
The passing of the policy is determined by the return value of the code. Use
```python
return True
```
to pass a policy and
```python
return False
```
to fail it.
## Available Functions
### `ak_message(message: str)`
Add a message, visible by the end user. This can be used to show the reason why they were denied.
Example:
```python
ak_message("Access denied")
return False
```
### `ak_user_has_authenticator(user: User, device_type: Optional[str] = None) -> bool` (2021.9+)
Check if a user has any authenticator devices. Only fully validated devices are counted.
Optionally, you can filter a specific device type. The following options are valid:
- `totp`
- `duo`
- `static`
- `webauthn`
Example:
```python
return ak_user_has_authenticator(request.user)
```
### `ak_call_policy(name: str, **kwargs) -> PolicyResult` (2021.12+)
Call another policy with the name *name*. Current request is passed to policy. Key-word arguments
can be used to modify the request's context.
Example:
```python
result = ak_call_policy("test-policy")
# result is a PolicyResult object, so you can access `.passing` and `.messages`.
return result.passing
result = ak_call_policy("test-policy-2", foo="bar")
# Inside the `test-policy-2` you can then use `request.context["foo"]`
return result.passing
```
import Functions from '../expressions/_functions.md'
## Variables
import Objects from '../expressions/_objects.md'
- `request`: A PolicyRequest object, which has the following properties:
- `request.user`: The current user, against which the policy is applied. See [User](../user-group/user.md#object-attributes)
- `request.http_request`: The Django HTTP Request. See ([Django documentation](https://docs.djangoproject.com/en/3.0/ref/request-response/#httprequest-objects))
- `request.obj`: A Django Model instance. This is only set if the policy is ran against an object.
- `request.context`: A dictionary with dynamic data. This depends on the origin of the execution.
- `geoip`: GeoIP object, which is added when GeoIP is enabled. See [GeoIP](https://geoip2.readthedocs.io/en/latest/#geoip2.models.City)
- `ak_is_sso_flow`: Boolean which is true if request was initiated by authenticating through an external provider.
- `ak_client_ip`: Client's IP Address or 255.255.255.255 if no IP Address could be extracted. Can be [compared](#comparing-ip-addresses), for example
```python
return ak_client_ip in ip_network('10.0.0.0/24')
# or
return ak_client_ip.is_private
```
See also [Python documentation](https://docs.python.org/3/library/ipaddress.html#ipaddress.ip_address)
Additionally, when the policy is executed from a flow, every variable from the flow's current context is accessible under the `context` object.
This includes the following:
- `context['prompt_data']`: Data which has been saved from a prompt stage or an external source.
- `context['application']`: The application the user is in the process of authorizing.
- `context['pending_user']`: The currently pending user, see [User](../user-group/user.md#object-attributes)
- `context['auth_method']`: Authentication method set (this value is set by password stages)
Depending on method, `context['auth_method_args']` is also set.
Can be any of:
- `password`: Standard password login
- `app_password`: App password (token)
Sets `context['auth_method_args']` to
```json
{
"token": {
"pk": "f6d639aac81940f38dcfdc6e0fe2a786",
"app": "authentik_core",
"name": "test (expires=2021-08-23 15:45:54.725880+00:00)",
"model_name": "token"
}
}
```
- `ldap`: LDAP bind authentication
Sets `context['auth_method_args']` to
```json
{
"source": {} // Information about the source used
}
```