uidとドキュメントidを一致させる方法

ユーザー登録した時に、uidとドキュメントを一致させる方法がわからなかった🤔

uidをFireStoreのコレクションのドキュメントidと一致させる方法を探していたのですが、中々見つからなかった....
そんな時に、強強エンジニアのtokkun5552さんの過去の記事を参考にしたら実現できたみたいです!

参考にした記事

https://qiita.com/tokkun5552/items/c81de7f662b5e3636082

先ずは、プロジェクトを作成する

flutter create user_add

必要なパッケージをインストールする

pubspec.yaml

name: user_add
description: A new Flutter project.

# The following line prevents the package from being accidentally published to
# pub.dev using `flutter pub publish`. This is preferred for private packages.
publish_to: 'none' # Remove this line if you wish to publish to pub.dev

# The following defines the version and build number for your application.
# A version number is three numbers separated by dots, like 1.2.43
# followed by an optional build number separated by a +.
# Both the version and the builder number may be overridden in flutter
# build by specifying --build-name and --build-number, respectively.
# In Android, build-name is used as versionName while build-number used as versionCode.
# Read more about Android versioning at https://developer.android.com/studio/publish/versioning
# In iOS, build-name is used as CFBundleShortVersionString while build-number used as CFBundleVersion.
# Read more about iOS versioning at
# https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
version: 1.0.0+1

environment:
  sdk: ">=2.17.3 <3.0.0"

# Dependencies specify other packages that your package needs in order to work.
# To automatically upgrade your package dependencies to the latest versions
# consider running `flutter pub upgrade --major-versions`. Alternatively,
# dependencies can be manually updated by changing the version numbers below to
# the latest version available on pub.dev. To see which dependencies have newer
# versions available, run `flutter pub outdated`.
dependencies:
  flutter:
    sdk: flutter


  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^1.0.2
  firebase_core: ^1.19.2
  cloud_firestore: ^3.3.0
  firebase_auth: ^3.4.2

dev_dependencies:
  flutter_test:
    sdk: flutter

  # The "flutter_lints" package below contains a set of recommended lints to
  # encourage good coding practices. The lint set provided by the package is
  # activated in the `analysis_options.yaml` file located at the root of your
  # package. See that file for information about deactivating specific lint
  # rules and activating additional ones.
  flutter_lints: ^2.0.0

# For information on the generic Dart part of this file, see the
# following page: https://dart.dev/tools/pub/pubspec

# The following section is specific to Flutter packages.
flutter:

  # The following line ensures that the Material Icons font is
  # included with your application, so that you can use the icons in
  # the material Icons class.
  uses-material-design: true

  # To add assets to your application, add an assets section, like this:
  # assets:
  #   - images/a_dot_burr.jpeg
  #   - images/a_dot_ham.jpeg

  # An image asset can refer to one or more resolution-specific "variants", see
  # https://flutter.dev/assets-and-images/#resolution-aware

  # For details regarding adding assets from package dependencies, see
  # https://flutter.dev/assets-and-images/#from-packages

  # To add custom fonts to your application, add a fonts section here,
  # in this "flutter" section. Each entry in this list should have a
  # "family" key with the font family name, and a "fonts" key with a
  # list giving the asset and other descriptors for the font. For
  # example:
  # fonts:
  #   - family: Schyler
  #     fonts:
  #       - asset: fonts/Schyler-Regular.ttf
  #       - asset: fonts/Schyler-Italic.ttf
  #         style: italic
  #   - family: Trajan Pro
  #     fonts:
  #       - asset: fonts/TrajanPro.ttf
  #       - asset: fonts/TrajanPro_Bold.ttf
  #         weight: 700
  #
  # For details regarding fonts from package dependencies,
  # see https://flutter.dev/custom-fonts/#from-packages

最近流行りのFirebase CLIを使用して、サクッと環境構築

https://firebase.flutter.dev/docs/cli

iOSだけ、設定をいじってます。FireStoreへの接続を高速化してくれる便利なものがあるのですが、使えないことがあるような?、エラーのログにその時に適切なバージョンが表示されるので、解決できるはず😅

こちらのGithubが公式ドキュメントのようです
https://github.com/invertase/firestore-ios-sdk-frameworks

Firebase CLIは便利ですが、iOSだけ自動で設定してくれないみたいです😇
先ずは、x-codeを設定する。
iOSの最小バージョンを13に設定する

次に、Podfileを設定する
Podfile

# Uncomment this line to define a global platform for your project
platform :ios, '13.0'

# CocoaPods analytics sends network stats synchronously affecting flutter build latency.
ENV['COCOAPODS_DISABLE_STATS'] = 'true'

project 'Runner', {
  'Debug' => :debug,
  'Profile' => :release,
  'Release' => :release,
}

def flutter_root
  generated_xcode_build_settings_path = File.expand_path(File.join('..', 'Flutter', 'Generated.xcconfig'), __FILE__)
  unless File.exist?(generated_xcode_build_settings_path)
    raise "#{generated_xcode_build_settings_path} must exist. If you're running pod install manually, make sure flutter pub get is executed first"
  end

  File.foreach(generated_xcode_build_settings_path) do |line|
    matches = line.match(/FLUTTER_ROOT\=(.*)/)
    return matches[1].strip if matches
  end
  raise "FLUTTER_ROOT not found in #{generated_xcode_build_settings_path}. Try deleting Generated.xcconfig, then run flutter pub get"
end

require File.expand_path(File.join('packages', 'flutter_tools', 'bin', 'podhelper'), flutter_root)

flutter_ios_podfile_setup

target 'Runner' do
  # FireStoreへの接続を高速化!
  # 今のバージョンだと9.3.0でないと依存関係を解決できない!
  # 9.3.0以下だとエラーが出てくる!
  pod 'FirebaseFirestore', :git => 'https://github.com/invertase/firestore-ios-sdk-frameworks.git', :tag => '9.3.0'
  use_frameworks!
  use_modular_headers!

  flutter_install_all_ios_pods File.dirname(File.realpath(__FILE__))
end

post_install do |installer|
  installer.pods_project.targets.each do |target|
    flutter_additional_ios_build_settings(target)
  end
end

Flutterのサンプルコード

main.dart

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
import 'package:user_add/firebase_options.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyAuthPage(),
    );
  }
}

class MyAuthPage extends StatefulWidget {
  @override
  _MyAuthPageState createState() => _MyAuthPageState();
}

class _MyAuthPageState extends State<MyAuthPage> {
  // 入力されたユーザーの名前
  String newUser = "";
  // 入力されたメールアドレス
  String newUserEmail = "";
  // 入力されたパスワード
  String newUserPassword = "";

  // ユーザー情報を登録する関数を定義
  Future<void> createAuth() async {
    // FirebaseAuthが用意しているメールアドレスとパスワードを登録する関数を定義
    final FirebaseAuth auth = FirebaseAuth.instance;
    UserCredential result = await auth.createUserWithEmailAndPassword(
      email: newUserEmail,
      password: newUserPassword,
    );
    // 上のFirebaseAuthから、uidを取得する変数を定義
    final user = result.user;
    final uuid = user?.uid;
    // usersコレクションを作成して、uidとドキュメントidを一致させるプログラムを定義
    final users = FirebaseFirestore.instance.collection('users').doc(uuid).set({
      'uid': uuid,
      'name': newUser,
      'email': newUserEmail,
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('ユーザー登録'),
      ),
      // キーボードで隠れて、黄色エラーが出るので
      // SingleChildScrollViewで、Centerウイジットをラップする
      body: SingleChildScrollView(
        child: Center(
          child: Container(
            padding: EdgeInsets.all(32),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: <Widget>[
                // かっこよくしたいので、画像を配置した!
                const CircleAvatar(
                  radius: 75,
                  // images.unsplash.comの画像のパスを貼り付ける
                  backgroundImage: NetworkImage(
                      'https://images.unsplash.com/photo-1658033014478-cc3b36e31a5e?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxlZGl0b3JpYWwtZmVlZHwxMDR8fHxlbnwwfHx8fA%3D%3D&auto=format&fit=crop&w=800&q=60'),
                ),
                const SizedBox(height: 40),
                TextFormField(
                  // テキスト入力のラベルを設定
                  decoration: InputDecoration(labelText: "ユーザー名"),
                  onChanged: (String value) {
                    setState(() {
                      newUser = value;
                    });
                  },
                ),
                const SizedBox(height: 8),
                TextFormField(
                  // テキスト入力のラベルを設定
                  decoration: InputDecoration(labelText: "メールアドレス"),
                  onChanged: (String value) {
                    setState(() {
                      newUserEmail = value;
                    });
                  },
                ),
                const SizedBox(height: 8),
                TextFormField(
                  decoration: InputDecoration(labelText: "パスワード（６文字以上）"),
                  // パスワードが見えないようにする
                  obscureText: true,
                  onChanged: (String value) {
                    setState(() {
                      newUserPassword = value;
                    });
                  },
                ),
                const SizedBox(height: 8),
                ElevatedButton(
                  onPressed: () async {
                    try {
                      // 作成した関数を実行する
                      createAuth();
                    } catch (e) {
                      print('登録に失敗しました!: $e');
                    }
                  },
                  child: Text("ユーザー登録"),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}

buildしてみる

Authenticationに、メールアドレスとパスワードが登録されました!

FireStoreにも情報が保存されています。uidとドキュメントidが一致しているようです。パスワードはこちらに保存すると不味いので、名前とメールアドレスだけしか保存しません。
パスワードの保存はAuthenticatonの方だけにします!

AndroidとFlutter Webも使ってみました!

最後に

このプログラムを書いて学んだことは、過去に書かれていた記事や新しい記事を見て、どうやって自分の書いているコードに落とし込むかでした。
先ずは、ブログとか見るよりは、公式ドキュメントを見てそれから人が書いたコードを動かしてみたり、参考にするのが良いですね。
コピペしただけだと動きませんので😅