From 7d14185e5884125b6e4993494cb50e6c62d5ba7a Mon Sep 17 00:00:00 2001
From: Jeff Huleatt <3759507+jhuleatt@users.noreply.github.com>
Date: Wed, 8 Apr 2026 10:17:27 -0400
Subject: [PATCH 1/6] add increment sample

---
 .../https-increment-number/.gitignore         |   5 +
 .../https-increment-number/README.md          |  56 +++++++++
 .../https-increment-number/bin/server.dart    | 107 ++++++++++++++++++
 .../https-increment-number/firebase.json      |   6 +
 .../https-increment-number/functions.yaml     |  23 ++++
 .../https-increment-number/pubspec.yaml       |  38 +++++++
 6 files changed, 235 insertions(+)
 create mode 100644 Dart/quickstarts/https-increment-number/.gitignore
 create mode 100644 Dart/quickstarts/https-increment-number/README.md
 create mode 100644 Dart/quickstarts/https-increment-number/bin/server.dart
 create mode 100644 Dart/quickstarts/https-increment-number/firebase.json
 create mode 100644 Dart/quickstarts/https-increment-number/functions.yaml
 create mode 100644 Dart/quickstarts/https-increment-number/pubspec.yaml

diff --git a/Dart/quickstarts/https-increment-number/.gitignore b/Dart/quickstarts/https-increment-number/.gitignore
new file mode 100644
index 0000000000..8ae1a6ef6d
--- /dev/null
+++ b/Dart/quickstarts/https-increment-number/.gitignore
@@ -0,0 +1,5 @@
+.dart_tool/
+.packages
+build/
+*.dart_tool
+pubspec.lock
diff --git a/Dart/quickstarts/https-increment-number/README.md b/Dart/quickstarts/https-increment-number/README.md
new file mode 100644
index 0000000000..a1ffb9ac0d
--- /dev/null
+++ b/Dart/quickstarts/https-increment-number/README.md
@@ -0,0 +1,56 @@
+# HTTPS Increment Number Quickstart
+
+This quickstart demonstrates how to handle HTTP requests for Cloud Functions using Dart. 
+It features two endpoints:
+- `incrementLocal`: Simple POST request that takes a local count and returns it incremented by 1.
+- `incrementSynced`: GET and POST endpoints that sync a counter variable to Firestore, returning the newly updated count.
+
+## Prerequisites
+
+1. Add your Firebase project to this Quickstart:
+   ```bash
+   firebase use --add
+   ```
+2. Enable Firestore in the Firebase Console and configure the emulator for local testing.
+
+## Local Testing
+
+First, fetch dependencies:
+```bash
+dart pub get
+```
+
+Then, you can use the Firebase CLI to test the function:
+```bash
+firebase emulators:start --only functions
+```
+
+Note: To test `incrementSynced`, ensure you also start the Firestore emulator: `firebase emulators:start --only functions,firestore`.
+
+### Testing `incrementLocal`
+
+In a separate terminal, use cURL to POST to the function (replace the URL with the one provided by the emulator):
+
+```bash
+curl -X POST http://127.0.0.1:5001/YOUR_PROJECT/us-central1/increment-local \
+     -H "Content-Type: application/json" \
+     -d '{"count": 5}'
+```
+
+You should see:
+```json
+{"message":"Local increment complete!","newCount":6}
+```
+
+### Testing `incrementSynced`
+
+To test using Firestore, fetch the initial count:
+```bash
+curl -X GET http://127.0.0.1:5001/YOUR_PROJECT/us-central1/increment-synced
+```
+
+Then increment it using POST:
+```bash
+curl -X POST http://127.0.0.1:5001/YOUR_PROJECT/us-central1/increment-synced \
+     -H "Content-Type: application/json"
+```
diff --git a/Dart/quickstarts/https-increment-number/bin/server.dart b/Dart/quickstarts/https-increment-number/bin/server.dart
new file mode 100644
index 0000000000..abac619d8a
--- /dev/null
+++ b/Dart/quickstarts/https-increment-number/bin/server.dart
@@ -0,0 +1,107 @@
+import 'dart:convert';
+import 'package:dart_firebase_admin/dart_firebase_admin.dart';
+import 'package:firebase_functions/firebase_functions.dart';
+import 'package:google_cloud_firestore/google_cloud_firestore.dart';
+
+const incrementCallable = 'incrementSynced';
+
+class IncrementResponse {
+  final String message;
+  final int newCount;
+
+  IncrementResponse({required this.message, required this.newCount});
+
+  Map<String, dynamic> toJson() => {
+        'message': message,
+        'newCount': newCount,
+      };
+}
+
+void main(List<String> args) async {
+  // Get firestore admin instance
+  final firestore = FirebaseApp.instance.firestore();
+
+  await fireUp(args, (firebase) {
+    
+    // [START dartHttpIncrementLocal]
+    firebase.https.onRequest(name: 'incrementLocal', (request) async {
+      print('Incrementing counter locally...');
+
+      if (request.method != 'POST') {
+        return Response(405, body: 'Method Not Allowed');
+      }
+
+      int currentCount = 0;
+      final bodyString = await request.readAsString();
+      if (bodyString.isNotEmpty) {
+        try {
+          final body = jsonDecode(bodyString) as Map<String, dynamic>;
+          currentCount = body['count'] as int? ?? 0;
+        } catch (e) {
+          return Response.badRequest(body: 'Invalid JSON request');
+        }
+      }
+
+      final response = IncrementResponse(
+        message: 'Local increment complete!',
+        newCount: currentCount + 1,
+      );
+
+      return Response(
+        200,
+        body: jsonEncode(response.toJson()),
+        headers: {'Content-Type': 'application/json'},
+      );
+    });
+    // [END dartHttpIncrementLocal]
+
+    // [START dartHttpIncrementSynced]
+    firebase.https.onRequest(name: incrementCallable, (request) async {
+      print('Processing synced counter request...');
+
+      // Get a reference to the counter document
+      final counterDoc = firestore.collection('counters').doc('global');
+
+      if (request.method == 'GET') {
+        // Handle GET request to read the current counter
+        final snapshot = await counterDoc.get();
+        final currentCount = snapshot.data()?['count'] as int? ?? 0;
+
+        final response = IncrementResponse(
+          message: 'Cloud-sync fetched!',
+          newCount: currentCount,
+        );
+
+        return Response(
+          200,
+          body: jsonEncode(response.toJson()),
+          headers: {'Content-Type': 'application/json'},
+        );
+      } else if (request.method == 'POST') {
+        // Handle POST request to increment the counter
+        final snapshot = await counterDoc.get();
+        final currentCount = snapshot.data()?['count'] as int? ?? 0;
+
+        // Increment count by one
+        await counterDoc.set({
+          'count': FieldValue.increment(1),
+        }, options: SetOptions.merge());
+
+        final response = IncrementResponse(
+          message: 'Cloud-sync complete!',
+          newCount: currentCount + 1,
+        );
+
+        return Response(
+          200,
+          body: jsonEncode(response.toJson()),
+          headers: {'Content-Type': 'application/json'},
+        );
+      } else {
+        return Response(405, body: 'Method Not Allowed');
+      }
+    });
+    // [END dartHttpIncrementSynced]
+
+  });
+}
diff --git a/Dart/quickstarts/https-increment-number/firebase.json b/Dart/quickstarts/https-increment-number/firebase.json
new file mode 100644
index 0000000000..2d344ac70f
--- /dev/null
+++ b/Dart/quickstarts/https-increment-number/firebase.json
@@ -0,0 +1,6 @@
+{
+  "functions": {
+    "source": ".",
+    "codebase": "dart-quickstarts-https-increment-number"
+  }
+}
diff --git a/Dart/quickstarts/https-increment-number/functions.yaml b/Dart/quickstarts/https-increment-number/functions.yaml
new file mode 100644
index 0000000000..05776f93ef
--- /dev/null
+++ b/Dart/quickstarts/https-increment-number/functions.yaml
@@ -0,0 +1,23 @@
+specVersion: v1alpha1
+requiredAPIs:
+  - api: cloudfunctions.googleapis.com
+    reason: Required for Cloud Functions
+endpoints:
+  increment-local:
+    platform: gcfv2
+    region:
+      - us-central1
+    httpsTrigger: {}
+    baseImageUri: us-central1-docker.pkg.dev/serverless-runtimes/google-24/runtimes/osonly24
+    command:
+      - ./bin/server
+    entryPoint: increment-local
+  increment-synced:
+    platform: gcfv2
+    region:
+      - us-central1
+    httpsTrigger: {}
+    baseImageUri: us-central1-docker.pkg.dev/serverless-runtimes/google-24/runtimes/osonly24
+    command:
+      - ./bin/server
+    entryPoint: increment-synced
diff --git a/Dart/quickstarts/https-increment-number/pubspec.yaml b/Dart/quickstarts/https-increment-number/pubspec.yaml
new file mode 100644
index 0000000000..0c28ce128e
--- /dev/null
+++ b/Dart/quickstarts/https-increment-number/pubspec.yaml
@@ -0,0 +1,38 @@
+name: https_increment_number
+description: HTTPS trigger examples showcasing state increment operations.
+publish_to: none
+
+environment:
+  sdk: ^3.11.0
+
+dependencies:
+  firebase_functions:
+    git:
+      url: https://github.com/firebase/firebase-functions-dart
+      ref: main
+  dart_firebase_admin:
+    git:
+      url: https://github.com/firebase/firebase-admin-dart
+      path: packages/dart_firebase_admin
+      ref: main
+  google_cloud_firestore:
+    git:
+      url: https://github.com/firebase/firebase-admin-dart
+      path: packages/google_cloud_firestore
+      ref: main
+
+dev_dependencies:
+  build_runner: ^2.10.5
+  lints: ^6.0.0
+
+dependency_overrides:
+  dart_firebase_admin:
+      git:
+        url: https://github.com/firebase/firebase-admin-dart
+        path: packages/dart_firebase_admin
+        ref: main
+  google_cloud_firestore:
+      git:
+        url: https://github.com/firebase/firebase-admin-dart
+        path: packages/google_cloud_firestore
+        ref: main

From 72fc89a2f2880965dd05ba84d62c8627f8eba07e Mon Sep 17 00:00:00 2001
From: Jeff Huleatt <3759507+jhuleatt@users.noreply.github.com>
Date: Wed, 8 Apr 2026 10:18:51 -0400
Subject: [PATCH 2/6] remove autogenerated file

---
 .../https-increment-number/functions.yaml     | 23 -------------------
 1 file changed, 23 deletions(-)
 delete mode 100644 Dart/quickstarts/https-increment-number/functions.yaml

diff --git a/Dart/quickstarts/https-increment-number/functions.yaml b/Dart/quickstarts/https-increment-number/functions.yaml
deleted file mode 100644
index 05776f93ef..0000000000
--- a/Dart/quickstarts/https-increment-number/functions.yaml
+++ /dev/null
@@ -1,23 +0,0 @@
-specVersion: v1alpha1
-requiredAPIs:
-  - api: cloudfunctions.googleapis.com
-    reason: Required for Cloud Functions
-endpoints:
-  increment-local:
-    platform: gcfv2
-    region:
-      - us-central1
-    httpsTrigger: {}
-    baseImageUri: us-central1-docker.pkg.dev/serverless-runtimes/google-24/runtimes/osonly24
-    command:
-      - ./bin/server
-    entryPoint: increment-local
-  increment-synced:
-    platform: gcfv2
-    region:
-      - us-central1
-    httpsTrigger: {}
-    baseImageUri: us-central1-docker.pkg.dev/serverless-runtimes/google-24/runtimes/osonly24
-    command:
-      - ./bin/server
-    entryPoint: increment-synced

From 33edd23350a505c18f6fd56039874b7064868852 Mon Sep 17 00:00:00 2001
From: Jeff Huleatt <3759507+jhuleatt@users.noreply.github.com>
Date: Wed, 8 Apr 2026 10:27:09 -0400
Subject: [PATCH 3/6] test in emulator

---
 .gitignore                                              | 2 ++
 Dart/quickstarts/https-increment-number/bin/server.dart | 6 +++---
 Dart/quickstarts/https-increment-number/firebase.json   | 3 +++
 Dart/quickstarts/https-increment-number/firestore.rules | 8 ++++++++
 4 files changed, 16 insertions(+), 3 deletions(-)
 create mode 100644 Dart/quickstarts/https-increment-number/firestore.rules

diff --git a/.gitignore b/.gitignore
index 127eafecb4..9535b26697 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,8 @@
 **/.firebase
 **/.firebaserc
 **/.runtimeconfig.json
+**/functions.yaml
+**/firestore-debug.log
 */npm-debug.log
 lerna-debug.log
 *~
diff --git a/Dart/quickstarts/https-increment-number/bin/server.dart b/Dart/quickstarts/https-increment-number/bin/server.dart
index abac619d8a..6d41d41bb4 100644
--- a/Dart/quickstarts/https-increment-number/bin/server.dart
+++ b/Dart/quickstarts/https-increment-number/bin/server.dart
@@ -18,9 +18,6 @@ class IncrementResponse {
 }
 
 void main(List<String> args) async {
-  // Get firestore admin instance
-  final firestore = FirebaseApp.instance.firestore();
-
   await fireUp(args, (firebase) {
     
     // [START dartHttpIncrementLocal]
@@ -59,6 +56,9 @@ void main(List<String> args) async {
     firebase.https.onRequest(name: incrementCallable, (request) async {
       print('Processing synced counter request...');
 
+      // Get firestore admin instance
+      final firestore = FirebaseApp.instance.firestore();
+
       // Get a reference to the counter document
       final counterDoc = firestore.collection('counters').doc('global');
 
diff --git a/Dart/quickstarts/https-increment-number/firebase.json b/Dart/quickstarts/https-increment-number/firebase.json
index 2d344ac70f..e155cc8e57 100644
--- a/Dart/quickstarts/https-increment-number/firebase.json
+++ b/Dart/quickstarts/https-increment-number/firebase.json
@@ -2,5 +2,8 @@
   "functions": {
     "source": ".",
     "codebase": "dart-quickstarts-https-increment-number"
+  },
+  "firestore": {
+    "rules": "firestore.rules"
   }
 }
diff --git a/Dart/quickstarts/https-increment-number/firestore.rules b/Dart/quickstarts/https-increment-number/firestore.rules
new file mode 100644
index 0000000000..0e33c9c2d4
--- /dev/null
+++ b/Dart/quickstarts/https-increment-number/firestore.rules
@@ -0,0 +1,8 @@
+rules_version = '2';
+service cloud.firestore {
+  match /databases/{database}/documents {
+    match /{document=**} {
+      allow read: if true;
+    }
+  }
+}

From 30f20c442e2702f1dc7e9bb15755a529815f3449 Mon Sep 17 00:00:00 2001
From: Jeff Huleatt <3759507+jhuleatt@users.noreply.github.com>
Date: Wed, 8 Apr 2026 10:34:15 -0400
Subject: [PATCH 4/6] use demo-example

---
 .../https-increment-number/README.md           | 18 +++++-------------
 1 file changed, 5 insertions(+), 13 deletions(-)

diff --git a/Dart/quickstarts/https-increment-number/README.md b/Dart/quickstarts/https-increment-number/README.md
index a1ffb9ac0d..a84020417d 100644
--- a/Dart/quickstarts/https-increment-number/README.md
+++ b/Dart/quickstarts/https-increment-number/README.md
@@ -5,13 +5,7 @@ It features two endpoints:
 - `incrementLocal`: Simple POST request that takes a local count and returns it incremented by 1.
 - `incrementSynced`: GET and POST endpoints that sync a counter variable to Firestore, returning the newly updated count.
 
-## Prerequisites
 
-1. Add your Firebase project to this Quickstart:
-   ```bash
-   firebase use --add
-   ```
-2. Enable Firestore in the Firebase Console and configure the emulator for local testing.
 
 ## Local Testing
 
@@ -20,19 +14,17 @@ First, fetch dependencies:
 dart pub get
 ```
 
-Then, you can use the Firebase CLI to test the function:
+Then, you can use the Firebase CLI to test the function locally. To ensure both endpoints work properly, make sure to start both the functions and firestore emulators:
 ```bash
-firebase emulators:start --only functions
+firebase emulators:start --project="demo-example" --only firestore,functions
 ```
 
-Note: To test `incrementSynced`, ensure you also start the Firestore emulator: `firebase emulators:start --only functions,firestore`.
-
 ### Testing `incrementLocal`
 
 In a separate terminal, use cURL to POST to the function (replace the URL with the one provided by the emulator):
 
 ```bash
-curl -X POST http://127.0.0.1:5001/YOUR_PROJECT/us-central1/increment-local \
+curl -X POST http://127.0.0.1:5001/demo-example/us-central1/increment-local \
      -H "Content-Type: application/json" \
      -d '{"count": 5}'
 ```
@@ -46,11 +38,11 @@ You should see:
 
 To test using Firestore, fetch the initial count:
 ```bash
-curl -X GET http://127.0.0.1:5001/YOUR_PROJECT/us-central1/increment-synced
+curl -X GET http://127.0.0.1:5001/demo-example/us-central1/increment-synced
 ```
 
 Then increment it using POST:
 ```bash
-curl -X POST http://127.0.0.1:5001/YOUR_PROJECT/us-central1/increment-synced \
+curl -X POST http://127.0.0.1:5001/demo-example/us-central1/increment-synced \
      -H "Content-Type: application/json"
 ```

From 5c40153ee7465d6be79becf5200ae6e3908dce97 Mon Sep 17 00:00:00 2001
From: Jeff Huleatt <3759507+jhuleatt@users.noreply.github.com>
Date: Wed, 8 Apr 2026 10:38:24 -0400
Subject: [PATCH 5/6] refine

---
 .../https-increment-number/bin/server.dart    | 22 ++++++-------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/Dart/quickstarts/https-increment-number/bin/server.dart b/Dart/quickstarts/https-increment-number/bin/server.dart
index 6d41d41bb4..c5699ddc47 100644
--- a/Dart/quickstarts/https-increment-number/bin/server.dart
+++ b/Dart/quickstarts/https-increment-number/bin/server.dart
@@ -3,23 +3,17 @@ import 'package:dart_firebase_admin/dart_firebase_admin.dart';
 import 'package:firebase_functions/firebase_functions.dart';
 import 'package:google_cloud_firestore/google_cloud_firestore.dart';
 
-const incrementCallable = 'incrementSynced';
-
 class IncrementResponse {
   final String message;
   final int newCount;
 
   IncrementResponse({required this.message, required this.newCount});
 
-  Map<String, dynamic> toJson() => {
-        'message': message,
-        'newCount': newCount,
-      };
+  Map<String, dynamic> toJson() => {'message': message, 'newCount': newCount};
 }
 
 void main(List<String> args) async {
   await fireUp(args, (firebase) {
-    
     // [START dartHttpIncrementLocal]
     firebase.https.onRequest(name: 'incrementLocal', (request) async {
       print('Incrementing counter locally...');
@@ -53,7 +47,7 @@ void main(List<String> args) async {
     // [END dartHttpIncrementLocal]
 
     // [START dartHttpIncrementSynced]
-    firebase.https.onRequest(name: incrementCallable, (request) async {
+    firebase.https.onRequest(name: 'incrementSynced', (request) async {
       print('Processing synced counter request...');
 
       // Get firestore admin instance
@@ -62,11 +56,12 @@ void main(List<String> args) async {
       // Get a reference to the counter document
       final counterDoc = firestore.collection('counters').doc('global');
 
-      if (request.method == 'GET') {
-        // Handle GET request to read the current counter
-        final snapshot = await counterDoc.get();
-        final currentCount = snapshot.data()?['count'] as int? ?? 0;
+      // Fetch the current counter value
+      final snapshot = await counterDoc.get();
+      final currentCount = snapshot.data()?['count'] as int? ?? 0;
 
+      if (request.method == 'GET') {
+        // Handle GET request to respond with the current counter
         final response = IncrementResponse(
           message: 'Cloud-sync fetched!',
           newCount: currentCount,
@@ -79,8 +74,6 @@ void main(List<String> args) async {
         );
       } else if (request.method == 'POST') {
         // Handle POST request to increment the counter
-        final snapshot = await counterDoc.get();
-        final currentCount = snapshot.data()?['count'] as int? ?? 0;
 
         // Increment count by one
         await counterDoc.set({
@@ -102,6 +95,5 @@ void main(List<String> args) async {
       }
     });
     // [END dartHttpIncrementSynced]
-
   });
 }

From 2ebee4de9b1bd62bbaefe0cd6b20b6def78fadf3 Mon Sep 17 00:00:00 2001
From: Jeff <3759507+jhuleatt@users.noreply.github.com>
Date: Fri, 10 Apr 2026 13:33:50 -0400
Subject: [PATCH 6/6] Refactor Dart counter sample to use a shared package
 (#1267)

- Created a new `shared` package to hold `IncrementResponse` and `incrementCallable`.
- Updated `https-increment-number/pubspec.yaml` to depend on the `shared` package.
- Replaced `https-increment-number/bin/server.dart` with updated user code, fixing syntax errors.
- Added appropriate `.gitignore` files to exclude generated Dart tooling and locks.

Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>
---
 .../https-increment-number/bin/server.dart    | 130 +++++++-----------
 .../https-increment-number/pubspec.yaml       |   2 +
 Dart/quickstarts/shared/.gitignore            |   5 +
 Dart/quickstarts/shared/lib/shared.dart       |  19 +++
 Dart/quickstarts/shared/pubspec.yaml          |   6 +
 5 files changed, 80 insertions(+), 82 deletions(-)
 create mode 100644 Dart/quickstarts/shared/.gitignore
 create mode 100644 Dart/quickstarts/shared/lib/shared.dart
 create mode 100644 Dart/quickstarts/shared/pubspec.yaml

diff --git a/Dart/quickstarts/https-increment-number/bin/server.dart b/Dart/quickstarts/https-increment-number/bin/server.dart
index c5699ddc47..12f11c1dc5 100644
--- a/Dart/quickstarts/https-increment-number/bin/server.dart
+++ b/Dart/quickstarts/https-increment-number/bin/server.dart
@@ -1,99 +1,65 @@
 import 'dart:convert';
-import 'package:dart_firebase_admin/dart_firebase_admin.dart';
 import 'package:firebase_functions/firebase_functions.dart';
-import 'package:google_cloud_firestore/google_cloud_firestore.dart';
-
-class IncrementResponse {
-  final String message;
-  final int newCount;
-
-  IncrementResponse({required this.message, required this.newCount});
-
-  Map<String, dynamic> toJson() => {'message': message, 'newCount': newCount};
-}
+import 'package:google_cloud_firestore/google_cloud_firestore.dart'
+    show FieldValue;
+import 'package:shared/shared.dart';
 
 void main(List<String> args) async {
   await fireUp(args, (firebase) {
-    // [START dartHttpIncrementLocal]
-    firebase.https.onRequest(name: 'incrementLocal', (request) async {
-      print('Incrementing counter locally...');
-
-      if (request.method != 'POST') {
-        return Response(405, body: 'Method Not Allowed');
-      }
-
-      int currentCount = 0;
-      final bodyString = await request.readAsString();
-      if (bodyString.isNotEmpty) {
-        try {
-          final body = jsonDecode(bodyString) as Map<String, dynamic>;
-          currentCount = body['count'] as int? ?? 0;
-        } catch (e) {
-          return Response.badRequest(body: 'Invalid JSON request');
-        }
-      }
-
-      final response = IncrementResponse(
-        message: 'Local increment complete!',
-        newCount: currentCount + 1,
-      );
-
-      return Response(
-        200,
-        body: jsonEncode(response.toJson()),
-        headers: {'Content-Type': 'application/json'},
-      );
-    });
-    // [END dartHttpIncrementLocal]
+    // Listen for calls to the http request and name defined in the shared package.
+    firebase.https.onRequest(name: incrementCallable, (request) async {
+      // In a production app, verify the user with request.auth?.uid here.
+      print('Incrementing counter on the server...');
 
-    // [START dartHttpIncrementSynced]
-    firebase.https.onRequest(name: 'incrementSynced', (request) async {
-      print('Processing synced counter request...');
-
-      // Get firestore admin instance
-      final firestore = FirebaseApp.instance.firestore();
+      // Get firestore database instance
+      final firestore = firebase.adminApp.firestore();
 
       // Get a reference to the counter document
       final counterDoc = firestore.collection('counters').doc('global');
 
-      // Fetch the current counter value
+      // Get the current snapshot for the count data
       final snapshot = await counterDoc.get();
-      final currentCount = snapshot.data()?['count'] as int? ?? 0;
-
-      if (request.method == 'GET') {
-        // Handle GET request to respond with the current counter
-        final response = IncrementResponse(
-          message: 'Cloud-sync fetched!',
-          newCount: currentCount,
-        );
-
-        return Response(
-          200,
-          body: jsonEncode(response.toJson()),
-          headers: {'Content-Type': 'application/json'},
-        );
-      } else if (request.method == 'POST') {
-        // Handle POST request to increment the counter
-
-        // Increment count by one
-        await counterDoc.set({
-          'count': FieldValue.increment(1),
-        }, options: SetOptions.merge());
-
-        final response = IncrementResponse(
-          message: 'Cloud-sync complete!',
-          newCount: currentCount + 1,
-        );
 
-        return Response(
-          200,
-          body: jsonEncode(response.toJson()),
-          headers: {'Content-Type': 'application/json'},
-        );
+      // Increment response we will send back
+      IncrementResponse incrementResponse;
+
+      // Check for the current count and if the snapshot exists
+      if (snapshot.data() case {'count': int value} when snapshot.exists) {
+        if (request.method == 'GET') {
+          // Get the current result
+          incrementResponse = IncrementResponse(
+            success: true,
+            message: 'Read-only sync complete',
+            newCount: value,
+          );
+        } else if (request.method == 'POST') {
+          // Increment count by one
+          final step = request.url.queryParameters['step'] as int? ?? 1;
+          await counterDoc.update({'count': FieldValue.increment(step)});
+          incrementResponse = IncrementResponse(
+            success: true,
+            message: 'Atomic increment complete',
+            newCount: value + 1,
+          );
+        } else {
+          return Response(405, body: 'Method Not Allowed');
+        }
       } else {
-        return Response(405, body: 'Method Not Allowed');
+        // Create a new document with a count of 1
+        await counterDoc.set({'count': 1});
+        incrementResponse = const IncrementResponse(
+          success: true,
+          message: 'Cloud-sync complete',
+          newCount: 1,
+        );
       }
+
+      // Return the response as JSON
+      return Response(
+        200,
+        body: jsonEncode(incrementResponse.toJson()),
+        headers: {'Content-Type': 'application/json'},
+      );
     });
-    // [END dartHttpIncrementSynced]
   });
 }
diff --git a/Dart/quickstarts/https-increment-number/pubspec.yaml b/Dart/quickstarts/https-increment-number/pubspec.yaml
index 0c28ce128e..b18643ae2d 100644
--- a/Dart/quickstarts/https-increment-number/pubspec.yaml
+++ b/Dart/quickstarts/https-increment-number/pubspec.yaml
@@ -6,6 +6,8 @@ environment:
   sdk: ^3.11.0
 
 dependencies:
+  shared:
+    path: ../shared
   firebase_functions:
     git:
       url: https://github.com/firebase/firebase-functions-dart
diff --git a/Dart/quickstarts/shared/.gitignore b/Dart/quickstarts/shared/.gitignore
new file mode 100644
index 0000000000..8ae1a6ef6d
--- /dev/null
+++ b/Dart/quickstarts/shared/.gitignore
@@ -0,0 +1,5 @@
+.dart_tool/
+.packages
+build/
+*.dart_tool
+pubspec.lock
diff --git a/Dart/quickstarts/shared/lib/shared.dart b/Dart/quickstarts/shared/lib/shared.dart
new file mode 100644
index 0000000000..bfbc6405b4
--- /dev/null
+++ b/Dart/quickstarts/shared/lib/shared.dart
@@ -0,0 +1,19 @@
+class IncrementResponse {
+  final bool success;
+  final String message;
+  final int newCount;
+
+  const IncrementResponse({
+    required this.success,
+    required this.message,
+    required this.newCount,
+  });
+
+  Map<String, dynamic> toJson() => {
+    'success': success,
+    'message': message,
+    'newCount': newCount,
+  };
+}
+
+const String incrementCallable = 'incrementSynced';
diff --git a/Dart/quickstarts/shared/pubspec.yaml b/Dart/quickstarts/shared/pubspec.yaml
new file mode 100644
index 0000000000..be30da55fa
--- /dev/null
+++ b/Dart/quickstarts/shared/pubspec.yaml
@@ -0,0 +1,6 @@
+name: shared
+description: Shared classes.
+publish_to: none
+
+environment:
+  sdk: ^3.11.0