feat(flutter_todos): Add firestore backend. Support compile time API selection.

examples/flutter_todos/.vscode/launch.json

@@ -29,6 +29,40 @@
       "type": "dart",
       "program": "lib/main_production.dart",
       "args": ["--flavor", "production", "--target", "lib/main_production.dart"]
+    },
+    {
+      "name": "Launch development (Firebase)",
+      "request": "launch",
+      "type": "dart",
+      "program": "lib/main_development.dart",
+      "args": [
+        "--flavor",
+        "development",
+        "--target",
+        "lib/main_development.dart"
+      ],
+      "toolArgs": ["--dart-define", "todos_api=firestore"]
+    },
+    {
+      "name": "Launch staging (Firebase)",
+      "request": "launch",
+      "type": "dart",
+      "program": "lib/main_staging.dart",
+      "args": ["--flavor", "staging", "--target", "lib/main_staging.dart"],
+      "toolArgs": ["--dart-define", "todos_api=firestore"]
+    },
+    {
+      "name": "Launch production (Firebase)",
+      "request": "launch",
+      "type": "dart",
+      "program": "lib/main_production.dart",
+      "args": [
+        "--flavor",
+        "production",
+        "--target",
+        "lib/main_production.dart"
+      ],
+      "toolArgs": ["--dart-define", "todos_api=firestore"]
     }
   ]
 }

examples/flutter_todos/android/app/build.gradle

@@ -50,7 +50,7 @@ android {
     defaultConfig {
         // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
         applicationId "com.example.verygoodcore.flutter_todos"
-        minSdkVersion flutter.minSdkVersion
+        minSdkVersion 21 // cloud_firestore >= 19, Auto MultiDex >=21
         targetSdkVersion flutter.targetSdkVersion
         versionCode flutterVersionCode.toInteger()
         versionName flutterVersionName

examples/flutter_todos/docs/firebase/README.md

@@ -0,0 +1,118 @@
+# Flutter Todos Firebase
+
+## Getting Started 🚀
+
+This project contains 3 flavors:
+
+- development
+- staging
+- production
+
+## Firestore - Setup 😍
+
+Using Firebase Firestore as the backend requires per-project setup.
+
+### Install
+
+```
+firebase login
+dart pub global activate flutterfire_cli
+```
+
+For more information follow the steps at https://firebase.google.com/docs/flutter/setup
+
+### Configure
+
+Based on the chosen flavor apply once the `flutterfire configure` command to integrate firebase into your project.
+
+```sh
+# Development
+$ flutterfire configure -a 'com.example.verygoodcore.flutter_todos.dev' -i 'com.example.verygoodcore.flutter-todos.dev'
+
+# Staging
+$ flutterfire configure -a 'com.example.verygoodcore.flutter_todos.stg' -i 'com.example.verygoodcore.flutter-todos.stg'
+
+# Production
+$ flutterfire configure -a 'com.example.verygoodcore.flutter_todos' -i 'com.example.verygoodcore.flutter-todos'
+```
+
+## Getting Started 🚀
+
+To run the desired flavor either use the launch configuration in VSCode/Android Studio or use the following commands:
+
+```sh
+# Development
+$ flutter run --flavor development --target lib/main_development.dart --dart-define=todos_api=firestore
+
+# Staging
+$ flutter run --flavor staging --target lib/main_staging.dart --dart-define=todos_api=firestore
+
+# Production
+$ flutter run --flavor production --target lib/main_production.dart --dart-define=todos_api=firestore
+```
+
+_\*Flutter Todos works on iOS, Android, and Web._
+
+---
+
+## FAQ
+
+Q: What does `flutterfire configure` changes in my project?
+
+A: The command registers app bundles and fetchs credentails from Firebase API required to communicate with the service.
+The credentials are writen locally into the project directories to be shipped with the app.
+
+**VALID to commit changes**
+
+```bash
+$ git status
+Changes not staged for commit:
+        modified:   examples/flutter_todos/android/app/build.gradle
+        modified:   examples/flutter_todos/android/build.gradle
+```
+
+```git
+$ git diff
+diff --git a/examples/flutter_todos/android/app/build.gradle b/examples/flutter_todos/android/app/build.gradle
+--- a/examples/flutter_todos/android/app/build.gradle
++++ b/examples/flutter_todos/android/app/build.gradle
+@@ -28,6 +28,9 @@ if (keystorePropertiesFile.exists()) {
+ }
+
+ apply plugin: 'com.android.application'
++// START: FlutterFire Configuration
++apply plugin: 'com.google.gms.google-services'
++// END: FlutterFire Configuration
+ apply plugin: 'kotlin-android'
+ apply from: "$flutterRoot/packages/flutter_tools/gradle/flutter.gradle"
+
+diff --git a/examples/flutter_todos/android/build.gradle b/examples/flutter_todos/android/build.gradle
+index ba6fe4a4..4f69aab2 100644
+--- a/examples/flutter_todos/android/build.gradle
++++ b/examples/flutter_todos/android/build.gradle
+@@ -7,6 +7,9 @@ buildscript {
+
+     dependencies {
+         classpath 'com.android.tools.build:gradle:7.1.2'
++        // START: FlutterFire Configuration
++        classpath 'com.google.gms:google-services:4.3.10'
++        // END: FlutterFire Configuration
+         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
+     }
+ }
+```
+
+**DO NOT Commit these changes**
+
+⚠️ Note: For both security and flavored app considerations credential **should not** be committed into git repo.
+
+```bash
+$ git status
+Untracked files:
+        examples/flutter_todos/android/app/google-services.json
+        examples/flutter_todos/ios/Runner/GoogleService-Info.plist
+        examples/flutter_todos/ios/firebase_app_id_file.json
+        examples/flutter_todos/lib/firebase_options.dart
+```
+
+_Use CI to integrate them into the artifact at runtime during the build phase of the app._

examples/flutter_todos/ios/Flutter/Debug.xcconfig

@@ -1,2 +1 @@
-#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig"
 #include "Generated.xcconfig"

examples/flutter_todos/ios/Flutter/Release.xcconfig

@@ -1,2 +1 @@
-#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"
 #include "Generated.xcconfig"

examples/flutter_todos/lib/main_development.dart

@@ -1,13 +1,14 @@
 import 'package:flutter/widgets.dart';
 import 'package:flutter_todos/bootstrap.dart';
-import 'package:local_storage_todos_api/local_storage_todos_api.dart';
+import 'package:todos_api_factory/todos_api_factory.dart';
 
-Future<void> main() async {
+Future<void> main(List<String> args) async {
   WidgetsFlutterBinding.ensureInitialized();
 
-  final todosApi = LocalStorageTodosApi(
-    plugin: await SharedPreferences.getInstance(),
-  );
+  const implementation =
+      String.fromEnvironment('todos_api', defaultValue: 'localStorage');
+
+  final todosApi = await TodosApiFactory.factory(implementation);
 
   bootstrap(todosApi: todosApi);
 }

examples/flutter_todos/lib/main_production.dart

@@ -1,13 +1,14 @@
 import 'package:flutter/widgets.dart';
 import 'package:flutter_todos/bootstrap.dart';
-import 'package:local_storage_todos_api/local_storage_todos_api.dart';
+import 'package:todos_api_factory/todos_api_factory.dart';
 
-Future<void> main() async {
+Future<void> main(List<String> args) async {
   WidgetsFlutterBinding.ensureInitialized();
 
-  final todosApi = LocalStorageTodosApi(
-    plugin: await SharedPreferences.getInstance(),
-  );
+  const implementation =
+      String.fromEnvironment('todos_api', defaultValue: 'localStorage');
+
+  final todosApi = await TodosApiFactory.factory(implementation);
 
   bootstrap(todosApi: todosApi);
 }

examples/flutter_todos/lib/main_staging.dart

@@ -1,13 +1,14 @@
 import 'package:flutter/widgets.dart';
 import 'package:flutter_todos/bootstrap.dart';
-import 'package:local_storage_todos_api/local_storage_todos_api.dart';
+import 'package:todos_api_factory/todos_api_factory.dart';
 
-Future<void> main() async {
+Future<void> main(List<String> args) async {
   WidgetsFlutterBinding.ensureInitialized();
 
-  final todosApi = LocalStorageTodosApi(
-    plugin: await SharedPreferences.getInstance(),
-  );
+  const implementation =
+      String.fromEnvironment('todos_api', defaultValue: 'localStorage');
+
+  final todosApi = await TodosApiFactory.factory(implementation);
 
   bootstrap(todosApi: todosApi);
 }

examples/flutter_todos/packages/firestore_todos_api/.gitignore

@@ -0,0 +1,7 @@
+# See https://www.dartlang.org/guides/libraries/private-files
+
+# Files and directories created by pub
+.dart_tool/
+.packages
+build/
+pubspec.lock

examples/flutter_todos/packages/firestore_todos_api/README.md

@@ -0,0 +1,11 @@
+# firestore_todos_api
+
+[![style: very good analysis][very_good_analysis_badge]][very_good_analysis_link]
+[![License: MIT][license_badge]][license_link]
+
+My new Firestore package
+
+[license_badge]: https://img.shields.io/badge/license-MIT-blue.svg
+[license_link]: https://opensource.org/licenses/MIT
+[very_good_analysis_badge]: https://img.shields.io/badge/style-very_good_analysis-B22C89.svg
+[very_good_analysis_link]: https://pub.dev/packages/very_good_analysis

examples/flutter_todos/packages/firestore_todos_api/analysis_options.yaml

@@ -0,0 +1 @@
+include: package:very_good_analysis/analysis_options.2.4.0.yaml

examples/flutter_todos/packages/firestore_todos_api/lib/firestore_todos_api.dart

@@ -0,0 +1,3 @@
+library firestore_todos_api;
+
+export 'src/firestore_todos_api.dart';

examples/flutter_todos/packages/firestore_todos_api/lib/src/firestore_todos_api.dart

@@ -0,0 +1,102 @@
+import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:todos_api/todos_api.dart';
+
+/// {@template firestore_todos_api}
+/// Firestore implementation for the Todos example
+/// {@endtemplate}
+class FirestoreTodosApi implements TodosApi {
+  /// {@macro firestore_todos_api}
+  FirestoreTodosApi({
+    required FirebaseFirestore firestore,
+  }) : _firestore = firestore;
+
+  final FirebaseFirestore _firestore;
+
+  /// a converter method for maintaining type-safety
+  late final todosCollection =
+      _firestore.collection('todos').withConverter<Todo>(
+            fromFirestore: (snapshot, _) => Todo.fromJson(snapshot.data()!),
+            toFirestore: (todo, _) => todo.toJson(),
+          );
+
+  /// This stream orders the [Todo]'s by the
+  /// time they were created, and then converts
+  /// them from a [DocumentSnapshot] into
+  /// a [Todo]
+  @override
+  Stream<List<Todo>> getTodos() {
+    return todosCollection.orderBy('id').snapshots().map(
+          (snapshot) => snapshot.docs.map((e) => e.data()).toList(),
+        );
+  }
+
+  /// This method first checks whether or not a todo exists
+  /// If it doesn't, then we add a timestamp to the todo in
+  /// order to preserve the order they were added
+  /// Else, we update the existing one
+  @override
+  Future<void> saveTodo(Todo todo) async {
+    final check = await todosCollection.where('id', isEqualTo: todo.id).get();
+
+    if (check.docs.isEmpty) {
+      await todosCollection.add(todo);
+    } else {
+      final currentTodoId = check.docs[0].reference.id;
+      await todosCollection.doc(currentTodoId).update(todo.toJson());
+    }
+  }
+
+  /// This method first checks to see if the todo
+  /// exists, and if so it deletes it
+  // TODO(fix): check out dismissiable bug
+
+  @override
+  Future<void> deleteTodo(String id) async {
+    final check = await todosCollection.where('id', isEqualTo: id).get();
+
+    if (check.docs.isEmpty) {
+      throw TodoNotFoundException();
+    } else {
+      final currentTodoId = check.docs[0].reference.id;
+      await todosCollection.doc(currentTodoId).delete();
+    }
+  }
+
+  /// This method uses the Batch write api for
+  /// executing multiple operations in a single call,
+  /// which in this case is to delete all the todos that
+  /// are marked completed
+  @override
+  Future<int> clearCompleted() {
+    final batch = _firestore.batch();
+    return todosCollection
+        .where('isCompleted', isEqualTo: true)
+        .get()
+        .then((querySnapshot) {
+      final completedTodosAmount = querySnapshot.docs.length;
+      for (final document in querySnapshot.docs) {
+        batch.delete(document.reference);
+      }
+      batch.commit();
+      return completedTodosAmount;
+    });
+  }
+
+  /// This method uses the Batch write api for
+  /// executing multiple operations in a single call,
+  /// which in this case is to mark all the todos as
+  /// completed
+  @override
+  Future<int> completeAll({required bool isCompleted}) {
+    final batch = _firestore.batch();
+    return todosCollection.get().then((querySnapshot) {
+      final completedTodosAmount = querySnapshot.docs.length;
+      for (final document in querySnapshot.docs) {
+        final completedTodo = document.data().copyWith(isCompleted: true);
+        batch.update(document.reference, completedTodo.toJson());
+      }
+      batch.commit();
+      return completedTodosAmount;
+    });
+  }
+}

examples/flutter_todos/packages/firestore_todos_api/pubspec.yaml

@@ -0,0 +1,21 @@
+name: firestore_todos_api
+description: My new Firestore package
+version: 1.0.0+1
+publish_to: none
+
+environment:
+  sdk: ">=2.17.0 <3.0.0"
+
+dependencies:
+  cloud_firestore: ^3.2.0
+  fake_cloud_firestore: ^1.2.4
+  flutter:
+    sdk: flutter
+  todos_api:
+    path: ../todos_api
+
+dev_dependencies:
+  coverage: ^1.3.2
+  mocktail: ^0.3.0
+  test: ^1.21.1
+  very_good_analysis: ^3.0.1