Initial Auth construct

packages/celest/example/celest/auth/auth.dart

@@ -0,0 +1,7 @@
+import 'package:celest/celest.dart';
+
+const auth = Auth(
+  providers: [
+    AuthProvider.google(),
+  ],
+);

packages/celest/lib/celest.dart

@@ -3,6 +3,10 @@ library celest;
 
 export 'package:celest_core/celest_core.dart';
 
+/// Auth
+export 'src/auth/auth.dart';
+export 'src/auth/auth_provider.dart';
+
 /// Config
 export 'src/config/env.dart';
 

packages/celest/lib/src/auth/auth.dart

@@ -0,0 +1,18 @@
+import 'package:celest/src/auth/auth_provider.dart';
+
+/// {@template celest.auth.auth}
+/// The authentication component of your Celest project.
+///
+/// The Auth widget defines the authentication providers which can be used to
+/// sign in to your Celest project.
+/// {@endtemplate}
+final class Auth {
+  /// {@macro celest.auth.auth}
+  const Auth({
+    required this.providers,
+  });
+
+  /// The authentication providers which can be used by your users when signing
+  /// in.
+  final List<AuthProvider> providers;
+}

packages/celest/lib/src/auth/auth_provider.dart

@@ -0,0 +1,16 @@
+/// {@template celest.auth.auth_provider}
+/// An authentication provider which can be used to sign in to Celest.
+///
+/// Currently, Celest supports the following authentication methods:
+/// - [AuthProvider.google] Sign in with Google
+/// {@endtemplate}
+sealed class AuthProvider {
+  const AuthProvider();
+
+  /// A provider which enables Sign in with Google.
+  const factory AuthProvider.google() = _GoogleAuthProvider;
+}
+
+final class _GoogleAuthProvider extends AuthProvider {
+  const _GoogleAuthProvider();
+}

packages/celest/lib/src/core/project.dart

@@ -11,8 +11,14 @@ class Project implements CloudWidget {
   /// {@macro celest.core.project}
   const Project({
     required this.name,
+    this.logoUrl,
   });
 
   /// The name of the project as its identified in your Celest backend.
   final String name;
+
+  /// The hosted URL of your project's logo.
+  ///
+  /// This is used by widgets like [Auth] to craft a custom login page.
+  final String? logoUrl;
 }