🔥 Skill: Firebase Integration

📋 Metadata

| Atributo | Valor | |----------|-------| | ID | flutter-firebase | | Nivel | 🟡 Intermedio | | Versión | 2.0.0 | | Keywords | firebase, firestore, auth, cloud-messaging, analytics, storage, remote-config, crashlytics, provider | | Referencia | FlutterFire |

🔑 Keywords para Invocación

• firebase
• firestore
• firebase-auth
• cloud-messaging
• firebase-analytics
• firebase-storage
• firebase-remote-config
• firebase-crashlytics
• provider
• @skill:firebase

Ejemplos de Prompts

Integra Firebase con auth y Firestore

Implementa Firebase Authentication y Cloud Messaging

@skill:firebase - Configura Firebase completo

📖 Descripción

Firebase Integration proporciona servicios backend completos: Authentication (Email/Password y Google Sign-In), Firestore Database, Cloud Storage, Push Notifications (FCM), Analytics (con tracking de screens, eventos personalizados, user ID y propiedades), Crashlytics y Remote Config. Incluye integración con Provider para state management y configuración multiplataforma con mejores prácticas.

⚠️ IMPORTANTE: Todos los comandos de este skill deben ejecutarse desde la raíz del proyecto (donde existe el directorio mobile/). El skill incluye verificaciones para asegurar que se está en el directorio correcto antes de ejecutar cualquier comando.

⚠️ IMPORTANTE: Todos los comandos de este skill deben ejecutarse desde la raíz del proyecto (donde existe el directorio mobile/). El skill incluye verificaciones para asegurar que se está en el directorio correcto antes de ejecutar cualquier comando.

✅ Cuándo Usar Este Skill

• Backend as a Service rápido
• Authentication con múltiples providers
• Base de datos en tiempo real
• Push notifications
• Analytics y Crashlytics
• Remote Config para A/B testing
• Rapid prototyping

❌ Cuándo NO Usar Este Skill

• Requieres control total del backend
• Costos de Firebase son prohibitivos
• Backend custom ya existe

🏗️ Estructura del Proyecto

lib/
├── core/
│   ├── firebase/
│   │   ├── firebase_options.dart (generado)
│   │   ├── firebase_config.dart
│   │   └── firebase_initialization.dart
│   └── services/
│       ├── analytics_service.dart
│       ├── crashlytics_service.dart
│       ├── remote_config_service.dart
│       └── storage_service.dart
│
├── features/
│   ├── authentication/
│   │   ├── data/
│   │   │   ├── datasources/
│   │   │   │   └── firebase_auth_datasource.dart
│   │   │   └── repositories/
│   │   │       └── auth_repository_impl.dart
│   │   ├── domain/
│   │   │   ├── entities/
│   │   │   │   └── user.dart
│   │   │   └── repositories/
│   │   │       └── auth_repository.dart
│   │   └── presentation/
│   │       ├── screens/
│   │       │   └── login_screen.dart
│   │       ├── providers/
│   │       │   └── auth_provider.dart
│   │       └── bloc/
│   │           └── auth_bloc.dart
│   │
│   ├── products/
│   │   ├── data/
│   │   │   ├── datasources/
│   │   │   │   └── firestore_products_datasource.dart
│   │   │   └── models/
│   │   │       └── product_model.dart
│   │   └── domain/
│   │       └── entities/
│   │           └── product.dart
│   │
│   └── notifications/
│       ├── data/
│       │   ├── datasources/
│       │   │   └── fcm_datasource.dart
│       │   └── services/
│       │       └── notification_service.dart
│       └── presentation/
│           └── screens/
│               └── notifications_screen.dart
│
└── main.dart

📦 Dependencias Requeridas

dependencies:
  flutter:
    sdk: flutter

  # Firebase Core
  firebase_core: ^2.24.2

  # Firebase Authentication
  firebase_auth: ^4.15.3
  google_sign_in: ^6.2.1

  # Cloud Firestore
  cloud_firestore: ^4.13.6

  # Cloud Storage
  firebase_storage: ^11.5.6

  # Cloud Messaging
  firebase_messaging: ^14.7.9
  flutter_local_notifications: ^16.3.0

  # Firebase Analytics
  firebase_analytics: ^10.7.4

  # Crashlytics
  firebase_crashlytics: ^3.4.8

  # Remote Config
  firebase_remote_config: ^4.3.8

  # State Management
  provider: ^6.1.1

  # Image Picker (para Storage)
  image_picker: ^1.0.7

  # Utils
  equatable: ^2.0.5
  dartz: ^0.10.1

dev_dependencies:
  flutter_test:
    sdk: flutter

⚙️ Configuración Inicial

1. Firebase CLI Setup

# Instalar Firebase CLI
npm install -g firebase-tools

# Login a Firebase
firebase login

# Verificar que estamos en la raíz del proyecto
if [ ! -d "mobile" ]; then
    echo "Error: Ejecuta este comando desde la raíz del proyecto"
    exit 1
fi

# Instalar FlutterFire CLI
dart pub global activate flutterfire_cli

# Configurar Firebase para el proyecto
cd mobile
flutterfire configure
cd ..
flutterfire configure

2. Android Configuration

// android/build.gradle
buildscript {
    dependencies {
        classpath 'com.google.gms:google-services:4.4.0'
        classpath 'com.google.firebase:firebase-crashlytics-gradle:2.9.9'
    }
}

// android/app/build.gradle
apply plugin: 'com.google.gms.google-services'
apply plugin: 'com.google.firebase.crashlytics'

android {
    defaultConfig {
        minSdkVersion 21  // Firebase requires 21+
    }
}

3. iOS Configuration

# ios/Podfile
platform :ios, '13.0'  # Firebase requires 13.0+

# Después de flutter_install_all_ios_pods
post_install do |installer|
  installer.pods_project.targets.each do |target|
    flutter_additional_ios_build_settings(target)
    target.build_configurations.each do |config|
      config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '13.0'
    end
  end
end

💻 Implementación

1. Firebase Initialization

// lib/main.dart
import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:firebase_crashlytics/firebase_crashlytics.dart';
import 'firebase_options.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();

  // Initialize Firebase
  await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );

  // Pass all uncaught errors to Crashlytics
  FlutterError.onError = FirebaseCrashlytics.instance.recordFlutterFatalError;

  runApp(const MyApp());
}

2. Firebase Authentication

// lib/features/authentication/data/datasources/firebase_auth_datasource.dart
import 'package:firebase_auth/firebase_auth.dart' as firebase_auth;
import 'package:google_sign_in/google_sign_in.dart';
import '../models/user_model.dart';

abstract class FirebaseAuthDataSource {
  Stream<UserModel?> get authStateChanges;
  Future<UserModel> signInWithEmailAndPassword(String email, String password);
  Future<UserModel> signUpWithEmailAndPassword(String email, String password);
  Future<UserModel> signInWithGoogle();
  Future<void> signOut();
  Future<void> sendPasswordResetEmail(String email);
  UserModel? getCurrentUser();
}

class FirebaseAuthDataSourceImpl implements FirebaseAuthDataSource {
  final firebase_auth.FirebaseAuth _firebaseAuth;
  final GoogleSignIn _googleSignIn;

  FirebaseAuthDataSourceImpl({
    firebase_auth.FirebaseAuth? firebaseAuth,
    GoogleSignIn? googleSignIn,
  })  : _firebaseAuth = firebaseAuth ?? firebase_auth.FirebaseAuth.instance,
        _googleSignIn = googleSignIn ?? GoogleSignIn();

  @override
  Stream<UserModel?> get authStateChanges {
    return _firebaseAuth.authStateChanges().map((firebaseUser) {
      return firebaseUser != null ? UserModel.fromFirebaseUser(firebaseUser) : null;
    });
  }

  @override
  Future<UserModel> signInWithEmailAndPassword(
    String email,
    String password,
  ) async {
    try {
      final credential = await _firebaseAuth.signInWithEmailAndPassword(
        email: email,
        password: password,
      );

      if (credential.user == null) {
        throw Exception('Sign in failed');
      }

      return UserModel.fromFirebaseUser(credential.user!);
    } on firebase_auth.FirebaseAuthException catch (e) {
      throw _handleAuthException(e);
    }
  }

  @override
  Future<UserModel> signUpWithEmailAndPassword(
    String email,
    String password,
  ) async {
    try {
      final credential = await _firebaseAuth.createUserWithEmailAndPassword(
        email: email,
        password: password,
      );

      if (credential.user == null) {
        throw Exception('Sign up failed');
      }

      return UserModel.fromFirebaseUser(credential.user!);
    } on firebase_auth.FirebaseAuthException catch (e) {
      throw _handleAuthException(e);
    }
  }

  @override
  Future<UserModel> signInWithGoogle() async {
    try {
      // Trigger the authentication flow
      final GoogleSignInAccount? googleUser = await _googleSignIn.signIn();

      if (googleUser == null) {
        throw Exception('Google sign in was cancelled');
      }

      // Obtain the auth details from the request
      final GoogleSignInAuthentication googleAuth = await googleUser.authentication;

      // Create a new credential
      final credential = firebase_auth.GoogleAuthProvider.credential(
        accessToken: googleAuth.accessToken,
        idToken: googleAuth.idToken,
      );

      // Sign in to Firebase with the Google credential
      final userCredential = await _firebaseAuth.signInWithCredential(credential);

      if (userCredential.user == null) {
        throw Exception('Google sign in failed');
      }

      return UserModel.fromFirebaseUser(userCredential.user!);
    } on firebase_auth.FirebaseAuthException catch (e) {
      throw _handleAuthException(e);
    } catch (e) {
      throw Exception('Google sign in failed: $e');
    }
  }

  @override
  Future<void> signOut() async {
    await Future.wait([
      _firebaseAuth.signOut(),
      _googleSignIn.signOut(),
    ]);
  }

  @override
  Future<void> sendPasswordResetEmail(String email) async {
    try {
      await _firebaseAuth.sendPasswordResetEmail(email: email);
    } on firebase_auth.FirebaseAuthException catch (e) {
      throw _handleAuthException(e);
    }
  }

  @override
  UserModel? getCurrentUser() {
    final firebaseUser = _firebaseAuth.currentUser;
    return firebaseUser != null ? UserModel.fromFirebaseUser(firebaseUser) : null;
  }

  Exception _handleAuthException(firebase_auth.FirebaseAuthException e) {
    switch (e.code) {
      case 'user-not-found':
        return Exception('No user found with this email');
      case 'wrong-password':
        return Exception('Wrong password');
      case 'email-already-in-use':
        return Exception('Email already in use');
      case 'weak-password':
        return Exception('Password is too weak');
      case 'invalid-email':
        return Exception('Invalid email format');
      default:
        return Exception('Authentication failed: ${e.message}');
    }
  }
}

3. Cloud Firestore

// lib/features/products/data/datasources/firestore_products_datasource.dart
import 'package:cloud_firestore/cloud_firestore.dart';
import '../models/product_model.dart';

abstract class FirestoreProductsDataSource {
  Stream<List<ProductModel>> getProductsStream();
  Future<List<ProductModel>> getProducts();
  Future<ProductModel> getProduct(String id);
  Future<ProductModel> createProduct(ProductModel product);
  Future<ProductModel> updateProduct(ProductModel product);
  Future<void> deleteProduct(String id);
}

class FirestoreProductsDataSourceImpl implements FirestoreProductsDataSource {
  final FirebaseFirestore _firestore;
  static const String _collection = 'products';

  FirestoreProductsDataSourceImpl({FirebaseFirestore? firestore})
      : _firestore = firestore ?? FirebaseFirestore.instance;

  @override
  Stream<List<ProductModel>> getProductsStream() {
    return _firestore
        .collection(_collection)
        .orderBy('createdAt', descending: true)
        .snapshots()
        .map((snapshot) {
      return snapshot.docs
          .map((doc) =