Dart on the Server: Build Your Backend in the Same Language as Your App

import 'dart:convert';
import 'package:shelf/shelf.dart';
import 'package:shelf/shelf_io.dart';
import 'package:shelf_router/shelf_router.dart';

// Simple in-memory store (replace with DB in production)
final Map<String, Map<String, dynamic>> _users = {
  '1': {'id': '1', 'name': 'Alice', 'email': '[email protected]'},
  '2': {'id': '2', 'name': 'Bob', 'email': '[email protected]'},
};

// CRUD Handlers
Response getUsers(Request req) =>
    _jsonResponse({'users': _users.values.toList()});

Response getUser(Request req, String id) {
  final user = _users[id];
  if (user == null) {
    return Response.notFound(jsonEncode({'error': 'User not found'}),
        headers: {'content-type': 'application/json'});
  }
  return _jsonResponse(user);
}

Future<Response> createUser(Request req) async {
  final body = jsonDecode(await req.readAsString()) as Map<String, dynamic>;
  final id = DateTime.now().millisecondsSinceEpoch.toString();
  _users[id] = {'id': id, ...body};
  return _jsonResponse(_users[id]!, statusCode: 201);
}

// Helper
Response _jsonResponse(dynamic data, {int statusCode = 200}) =>
    Response(statusCode,
        body: jsonEncode(data),
        headers: {'content-type': 'application/json'});

void main() async {
  final router = Router()
    ..get('/users', getUsers)
    ..get('/users/<id>', getUser)
    ..post('/users', createUser);

  final handler =
      Pipeline().addMiddleware(logRequests()).addHandler(router);

  final server = await serve(handler, 'localhost', 8080);
  print('API running at http://localhost:${server.port}');
}