使用 Firebase

有关入门和使用 Firebase JS SDK 和 React Native Firebase 库的指南。

Firebase 是一个后端即服务 (BaaS) 应用开发平台，提供托管后端服务，例如实时数据库、云存储、身份验证、崩溃报告、分析等。它建立在 Google 的基础设施之上，并可自动扩展。

¥Firebase is a Backend-as-a-Service (BaaS) app development platform that provides hosted backend services such as real-time database, cloud storage, authentication, crash reporting, analytics, and so on. It is built on Google's infrastructure and scales automatically.

你可以通过两种不同的方式在项目中使用 Firebase：

¥There are two different ways you can use Firebase in your projects:

• 使用 Firebase JS SDK

  ¥Using Firebase JS SDK

• 使用 React Native Firebase

  ¥Using React Native Firebase

React Native 同时支持 JS SDK 和原生 SDK。以下部分将指导你了解何时使用哪个 SDK 以及在 Expo 项目中使用 Firebase 所需的所有配置步骤。

¥React Native supports both the JS SDK and the native SDK. The following sections will guide you through when to use which SDK and all the configuration steps required to use Firebase in your Expo projects.

先决条件

¥Prerequisites

在继续之前，请确保你已创建一个新的 Firebase 项目或使用 Firebase 控制台。

¥Before proceeding, make sure that you have created a new Firebase project or have an existing one using the Firebase console.

使用 Firebase JS SDK

¥Using Firebase JS SDK

Firebase JS SDK 是一个 JavaScript 库，可让你与项目中的 Firebase 服务进行交互。它支持 React Native 应用中的 验证、Firestore、实时数据库 和 贮存 等服务。

¥The Firebase JS SDK is a JavaScript library that allows you to interact with Firebase services in your project. It supports services such as Authentication, Firestore, Realtime Database, and Storage in a React Native app.

何时使用 Firebase JS SDK

¥When to use Firebase JS SDK

当你满足以下条件时，可以考虑使用 Firebase JS SDK：

¥You can consider using the Firebase JS SDK when you:

• 想要在你的应用中使用 Firebase 服务，例如身份验证、Firestore、实时数据库和存储，并且想要使用 Expo 开发你的应用。

  ¥Want to use Firebase services such as Authentication, Firestore, Realtime Database, and Storage in your app and want to develop your app with Expo Go.

• 想要快速开始使用 Firebase 服务。

  ¥Want a quick start with Firebase services.

• 想要创建适用于 Android、iOS 和 Web 的通用应用。

  ¥Want to create a universal app for Android, iOS, and the web.

注意事项

¥Caveats

Firebase JS SDK 不支持移动应用的所有服务。其中一些服务包括 Analytics、Dynamic Links 和 Crashlytics。如果你想使用这些服务，请参阅 React Native Firebase 部分。

¥Firebase JS SDK does not support all services for mobile apps. Some of these services are Analytics, Dynamic Links and Crashlytics. See the React Native Firebase section if you want to use these services.

安装并初始化 Firebase JS SDK

¥Install and initialize Firebase JS SDK

以下小节使用 firebase@9.x.x。Expo SDK 不会强制或推荐在你的应用中使用任何特定版本的 Firebase。

¥The following sub-sections use firebase@9.x.x. Expo SDK does not enforce or recommend any specific version of Firebase to use in your app.

如果你在项目中使用旧版本的 firebase 库，则可能需要在 Firebase JS SDK 文档 的帮助下调整代码示例以匹配你正在使用的版本。

¥If you are using an older version of the firebase library in your project, you may have to adapt the code examples to match the version that you are using with the help of the Firebase JS SDK documentation.

import { initializeApp } from 'firebase/app';

// Optionally import the services that you want to use
// import {...} from 'firebase/auth';
// import {...} from 'firebase/database';
// import {...} from 'firebase/firestore';
// import {...} from 'firebase/functions';
// import {...} from 'firebase/storage';

// Initialize Firebase
const firebaseConfig = {
  apiKey: 'api-key',
  authDomain: 'project-id.firebaseapp.com',
  databaseURL: 'https://project-id.firebaseio.com',
  projectId: 'project-id',
  storageBucket: 'project-id.appspot.com',
  messagingSenderId: 'sender-id',
  appId: 'app-id',
  measurementId: 'G-measurement-id',
};

const app = initializeApp(firebaseConfig);
// For more information on how to access Firebase in your project,
// see the Firebase documentation: https://firebase.google.com/docs/web/setup#access-firebase

const { getDefaultConfig } = require('@expo/metro-config');

const defaultConfig = getDefaultConfig(__dirname);
defaultConfig.resolver.sourceExts.push('cjs');

module.exports = defaultConfig;

Next steps

Using React Native Firebase

React Native Firebase provides access to native code by wrapping the native SDKs for Android and iOS into a JavaScript API. Each Firebase service is available as a module that can be added as a dependency to your project. For example, the auth module provides access to the Firebase Authentication service.

When to use React Native Firebase

You can consider using React Native Firebase when:

• Your app requires access to Firebase services not supported by the Firebase JS SDK, such as Dynamic Links, Crashlytics, and so on. For more information on the additional capabilities offered by the native SDK's, see React Native Firebase documentation.
• You want to use native SDKs in your app.
• You have a bare React Native app with React Native Firebase already configured but are migrating to use Expo SDK.
• You want to use Firebase Analytics in your app.

Caveats

React Native Firebase requires custom native code and cannot be used with Expo Go.

Install and initialize React Native Firebase

下一步

¥Next steps

配置 React Native Firebase 库后，你可以在 Expo 项目中使用它提供的任何模块。

¥After configuring React Native Firebase library, you can use any module it provides in your Expo project.