flutter_policy_engine 2.0.0

A lightweight, extensible policy engine for Flutter enabling RBAC and basic ABAC with Clean Architecture, injectable logger, and persistent storage.

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter_policy_engine_example/policy_engine_demo.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Policy Engine v2 Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const HomeScreen(),
    );
  }
}

class HomeScreen extends StatelessWidget {
  const HomeScreen({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Flutter Policy Engine v2'),
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
      ),
      body: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Card(
              child: Padding(
                padding: const EdgeInsets.all(24),
                child: Column(
                  children: [
                    const Icon(Icons.security, size: 64, color: Colors.blue),
                    const SizedBox(height: 16),
                    Text(
                      'Flutter Policy Engine',
                      style: Theme.of(context).textTheme.headlineMedium,
                      textAlign: TextAlign.center,
                    ),
                    const SizedBox(height: 4),
                    Text(
                      'v2 — Clean Architecture, RBAC + ABAC',
                      style: Theme.of(context)
                          .textTheme
                          .bodyMedium
                          ?.copyWith(color: Colors.grey),
                      textAlign: TextAlign.center,
                    ),
                  ],
                ),
              ),
            ),
            const SizedBox(height: 24),
            _DemoButton(
              label: 'Basic RBAC Demo',
              subtitle: 'Inline policy map, PolicyGate widget',
              icon: Icons.play_arrow,
              color: Colors.blue,
              onTap: () => Navigator.push(
                context,
                MaterialPageRoute<void>(
                  builder: (_) => const PolicyEngineDemo(),
                ),
              ),
            ),
            const SizedBox(height: 12),
            _DemoButton(
              label: 'Role Management Demo',
              subtitle: 'Add / update / remove roles at runtime',
              icon: Icons.admin_panel_settings,
              color: Colors.orange,
              onTap: () => Navigator.push(
                context,
                MaterialPageRoute<void>(
                  builder: (_) => const RoleManagementDemo(),
                ),
              ),
            ),
            const SizedBox(height: 12),
            _DemoButton(
              label: 'JSON Assets Demo',
              subtitle: 'Load policies from a bundled JSON asset',
              icon: Icons.file_copy,
              color: Colors.teal,
              onTap: () => Navigator.push(
                context,
                MaterialPageRoute<void>(
                  builder: (_) => const JsonAssetsDemo(),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _DemoButton extends StatelessWidget {
  const _DemoButton({
    required this.label,
    required this.subtitle,
    required this.icon,
    required this.color,
    required this.onTap,
  });

  final String label;
  final String subtitle;
  final IconData icon;
  final Color color;
  final VoidCallback onTap;

  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      onPressed: onTap,
      style: ElevatedButton.styleFrom(
        backgroundColor: color,
        foregroundColor: Colors.white,
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 20),
        alignment: Alignment.centerLeft,
      ),
      child: Row(
        children: [
          Icon(icon, size: 28),
          const SizedBox(width: 16),
          Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(label, style: const TextStyle(fontWeight: FontWeight.bold)),
              Text(
                subtitle,
                style: const TextStyle(fontSize: 12, color: Colors.white70),
              ),
            ],
          ),
        ],
      ),
    );
  }
}