microsoft.md

Microsoft Tutorial

This is a quick tutorial on how to configure Microsoft (Azure AD) authentication.

First you'll need a registered application in the Microsoft Entra admin center, in order to get your OAuth 2.0 credentials.

1. Under the Entra ID fan click App registrations
2. Click New registration
3. Enter a name for your application
4. Under Redirect URI, select Web and enter your callback URL. E.g. http://localhost:4000/auth/user/microsoft/callback
5. Click Register
6. From the app's Overview page, copy the Application (client) ID — this is your client_id
7. From the same Overview page, copy the Directory (tenant) ID — you'll need this if you want to restrict sign-in to a specific tenant
8. Navigate to Certificates & secrets > + New client secret, add a description and expiry, then copy the secret Value — this is your client_secret

Next we configure our resource to use Microsoft credentials:

defmodule MyApp.Accounts.User do
  use Ash.Resource,
    extensions: [AshAuthentication],
    domain: MyApp.Accounts

  attributes do
    ...
  end

  authentication do
    strategies do
      microsoft do
        client_id MyApp.Secrets
        redirect_uri MyApp.Secrets
        client_secret MyApp.Secrets
      end
    end
  end
end

By default the strategy uses the common tenant endpoint, which allows any Microsoft account (personal, work, or school). To restrict sign-in to a specific Azure tenant, override base_url:

microsoft do
  client_id MyApp.Secrets
  redirect_uri MyApp.Secrets
  client_secret MyApp.Secrets
  base_url "https://login.microsoftonline.com/YOUR_TENANT_ID/v2.0"
end

Please check the guide on how to properly configure your Secrets. Then we need to define an action that will handle the oauth2 flow, for the Microsoft case it is :register_with_microsoft — it will handle both cases for our resource, user registration & login.

defmodule MyApp.Accounts.User do
  require Ash.Resource.Change.Builtins
  use Ash.Resource,
    extensions: [AshAuthentication],
    domain: MyApp.Accounts

  # ...
  actions do
    create :register_with_microsoft do
      argument :user_info, :map, allow_nil?: false
      argument :oauth_tokens, :map, allow_nil?: false
      upsert? true
      upsert_identity :unique_email

      change AshAuthentication.GenerateTokenChange

      # Required if you have the `identity_resource` configuration enabled.
      change AshAuthentication.Strategy.OAuth2.IdentityChange

      change fn changeset, _ ->
        user_info = Ash.Changeset.get_argument(changeset, :user_info)

        Ash.Changeset.change_attributes(changeset, Map.take(user_info, ["email"]))
      end

      # Required if you're using the password & confirmation strategies
      upsert_fields []
      change set_attribute(:confirmed_at, &DateTime.utc_now/0)
    end
  end

  # ...

end

Ensure you set the hashed_password to allow_nil? if you are also using the password strategy.

defmodule MyApp.Accounts.User do
  # ...
  attributes do
    # ...
    attribute :hashed_password, :string, allow_nil?: true, sensitive?: true
  end
  # ...
end

And generate and run migrations in that case.

mix ash.codegen make_hashed_password_nullable
mix ash.migrate