FlutterFire CLI で Firebase と連携し Firestore からデータ取得

# platform :ios, '9.0'
platform :ios, '10.12'

i Found 3 Firebase projects.
✔ Select a Firebase project to configure your Flutter application with · <create a new project>
✔ Enter a project id for your new Firebase project (e.g. my-cool-project) · firestore-read-sample
i New Firebase project firestore-read-sample created succesfully.
✔ Which platforms should your configuration support (use arrow keys & space to select)? · ios
i Firebase ios app com.runble1.firestoreRead.firestoreRead is not registered on Firebase project firestore-read-sample.
i Registered a new Firebase ios app on Firebase project firestore-read-sample.

Firebase configuration file lib/firebase_options.dart generated successfully with the following Firebase apps:

Platform  Firebase App Id
ios       1:495423162590:ios:f883afab50eb61df499a4f

Learn more about using this file in the FlutterFire documentation:
 > https://firebase.flutter.dev/docs/cli

// File generated by FlutterFire CLI.
// ignore_for_file: lines_longer_than_80_chars
import 'package:firebase_core/firebase_core.dart' show FirebaseOptions;
import 'package:flutter/foundation.dart'
    show defaultTargetPlatform, kIsWeb, TargetPlatform;

/// Default [FirebaseOptions] for use with your Firebase apps.
///
/// Example:
/// ```dart
/// import 'firebase_options.dart';
/// // ...
/// await Firebase.initializeApp(
///   options: DefaultFirebaseOptions.currentPlatform,
/// );
/// ```
class DefaultFirebaseOptions {
  static FirebaseOptions get currentPlatform {
    if (kIsWeb) {
      throw UnsupportedError(
        'DefaultFirebaseOptions have not been configured for web - '
        'you can reconfigure this by running the FlutterFire CLI again.',
      );
    }
    // ignore: missing_enum_constant_in_switch
    switch (defaultTargetPlatform) {
      case TargetPlatform.android:
        throw UnsupportedError(
          'DefaultFirebaseOptions have not been configured for android - '
          'you can reconfigure this by running the FlutterFire CLI again.',
        );
      case TargetPlatform.iOS:
        return ios;
      case TargetPlatform.macOS:
        throw UnsupportedError(
          'DefaultFirebaseOptions have not been configured for macos - '
          'you can reconfigure this by running the FlutterFire CLI again.',
        );
    }

    throw UnsupportedError(
      'DefaultFirebaseOptions are not supported for this platform.',
    );
  }

  static const FirebaseOptions ios = FirebaseOptions(
    apiKey: 'aaaa',
    appId: '1:1111:bbbb',
    messagingSenderId: '2222',
    projectId: 'firestore-read-sample',
    storageBucket: 'firestore-read-sample.appspot.com',
    iosClientId: '3333-fnd0ta0494t9bhnk3i6sp823n4484rdi.apps.googleusercontent.com',
    iosBundleId: 'com.runble1.firestoreRead.firestoreRead',
  );
}

import 'package:flutter/material.dart';

import 'firebase_options.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:cloud_firestore/cloud_firestore.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Firestore Read Sample',
      home: UserListPage(),
    );
  }
}

class UserListPage extends StatelessWidget {
  final Stream<QuerySnapshot> _usersStream = FirebaseFirestore.instance.collection('users').snapshots();
  //print(_usersStream);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('ユーザ一覧'),
      ),
      body: Center(
        child: StreamBuilder<QuerySnapshot>(
          stream: _usersStream,
          builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
            //if (snapshot.hasError) {
            //  return Text('Something went wrong');
            //}
            if (snapshot.connectionState == ConnectionState.waiting) {
              return Text("Loading");
            }

            return ListView(
              children: snapshot.data!.docs.map((DocumentSnapshot document) {
                Map<String, dynamic> data = document.data()! as Map<String, dynamic>;
                return ListTile(
                  title: Text(data['full_name']),
                  subtitle: Text(data['company']),
                );
              }).toList(),
            );
          },
        ),
      ),
    );
  }
}

i New Firebase project flutter-firestore-runble1 created succesfully.
FirebaseCommandException: An error occured on the Firebase CLI when attempting to run a command.
COMMAND: firebase projects:create flutter-firestore-runble1 --json
ERROR: Failed to create project because there is already a project with ID flutter-firestore-runble1. Please try again with a unique project ID.

platform :ios, '10.12'

Exception has occurred.
FirebaseException ([core/not-initialized] Firebase has not been correctly initialized.

Usually this means you've attempted to use a Firebase service before calling `Firebase.initializeApp`.

View the documentation for more information: https://firebase.flutter.dev/docs/overview#initialization
    )

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();
  runApp(MyApp());
}

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

children: snapshot.data!.docs.map((DocumentSnapshot document) {

rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    match /{document=**} {
      allow read, write: if
          request.time < timestamp.date(2022, 3, 29);
    }
  }
}