# Upgrading

## Upgrading to version 4.0.0

Version 4.0.0 of AshAuthentication adds support for Ash 3.0 and in line with [a number of changes in Ash](`e:ash:upgrading-to-3.0.html`) there are some corresponding changes to Ash Authentication:

- Token generation is enabled by default, meaning that you will have to explicitly set [`authentication.tokens.enabled?`](documentation/dsls/DSL-AshAuthentication.md#authentication-tokens-enabled?) to `false` if you don't need them.

- Sign in tokens are enabled by default in the password strategy. What this means is that instead of returning a regular user token on sign-in in the user's metadata, we generate a short-lived token which can be used to actually sign the user in. This is specifically to allow live-view based sign-in UIs to display an authentication error without requiring a page-load.

## Upgrading to version 3.6.0.

As of version 3.6.0 the `TokenResource` extension adds the `subject` attribute
which allows us to more easily match tokens to specific users. This unlocks
some new use-cases (eg sign out everywhere).

This means that you will need to generate new migrations and migrate your
database.

### Upgrade steps:

> ### Warning {: .warning}
>
> If you already have tokens stored in your database then the migration will
> likely throw a migration error due to the new `NOT NULL` constraint on
> `subject`. If this happens then you can either delete all your tokens or
> explicitly add the `subject` attribute to your resource with `allow_nil?` set
> to `true`. eg:
>
> ```elixir
> attributes do
>   attribute :subject, :string, allow_nil?: true
> end
> ```

1. Run `mix ash_postgres.generate_migrations --name=add_subject_to_token_resource`
2. Run `mix ash_postgres.migrate`
3. 🎉