Cities: add first basic Vector Search example using Cities

.gitlab-ci.yml

@@ -34,17 +34,21 @@ analyze:
     - dart pub get --directory=generator
     - dart pub get --directory=objectbox
     - dart pub get --directory=objectbox_test
+    - dart pub get --directory=objectbox/example/dart-native/vectorsearch_cities
     # Generate code
     - cd benchmark
     - dart run build_runner build
     - cd ../objectbox_test
     - dart run build_runner build
-    - cd ..
+    - cd ../objectbox/example/dart-native/vectorsearch_cities
+    - dart run build_runner build
+    - cd ../../../.. # back to repo root
     # Analyze Dart packages
     - dart analyze benchmark
     - dart analyze generator
     - dart analyze objectbox
     - dart analyze objectbox_test
+    - dart analyze objectbox/example/dart-native/vectorsearch_cities
     # Check formatting of all packages
     - dart format --set-exit-if-changed --fix .
 
@@ -120,3 +124,18 @@ coverage:
   artifacts:
     paths:
       - objectbox/coverage/html/
+
+# For the Dart Native example compiles and runs the executable (analysis and code formatting is 
+# checked by analyze job).
+dart-examples-test:
+  extends: .cache
+  stage: test
+  tags: [ x64, linux, docker ]
+  image: dart:$DART_VERSION
+  script:
+    - cd objectbox/example/dart-native/vectorsearch_cities
+    - dart pub get
+    - dart run build_runner build
+    - ../../../../install.sh
+    - dart compile exe bin/vectorsearch_cities.dart
+    - ./bin/vectorsearch_cities.exe

objectbox/CHANGELOG.md

@@ -1,6 +1,7 @@
 ## latest
 
 * Export `ObjectWithScore` and `IdWithScore` used by the new find with score `Query` methods. [#637]
+* Add simple `vectorsearch_cities` Dart Native example application.
 
 ## 4.0.0 (2024-05-15)
 

objectbox/example/README.md

@@ -3,6 +3,8 @@ ObjectBox Examples
 
 There are several example apps and tutorials available:
 
+* [vectorsearch_cities](dart-native/vectorsearch_cities): a Dart Native example app using Vector
+  Search to find neighbors of cities.
 * [objectbox_demo_relations](flutter/objectbox_demo_relations): our main Flutter example app showing 
   all basics and how to use relations.
 * [event_management_tutorial](flutter/event_management_tutorial): an event management Flutter app 

objectbox/example/dart-native/vectorsearch_cities/.gitignore

@@ -0,0 +1,3 @@
+# https://dart.dev/guides/libraries/private-files
+# Created by `dart pub`
+.dart_tool/

objectbox/example/dart-native/vectorsearch_cities/README.md

@@ -0,0 +1,8 @@
+# Vector-Search Example: Cities
+
+This is a simple example application to demonstrate the Vector Search feature of ObjectBox.
+It searches for nearest neighbors of a city.
+
+## Docs
+- [Getting started with ObjectBox](https://docs.objectbox.io/getting-started)
+- [ANN Vector Search](https://docs.objectbox.io/ann-vector-search)

objectbox/example/dart-native/vectorsearch_cities/analysis_options.yaml

@@ -0,0 +1,30 @@
+# This file configures the static analysis results for your project (errors,
+# warnings, and lints).
+#
+# This enables the 'recommended' set of lints from `package:lints`.
+# This set helps identify many issues that may lead to problems when running
+# or consuming Dart code, and enforces writing Dart using a single, idiomatic
+# style and format.
+#
+# If you want a smaller set of lints you can change this to specify
+# 'package:lints/core.yaml'. These are just the most critical lints
+# (the recommended set includes the core lints).
+# The core lints are also what is used by pub.dev for scoring packages.
+
+include: package:lints/recommended.yaml
+
+# Uncomment the following section to specify additional rules.
+
+# linter:
+#   rules:
+#     - camel_case_types
+
+# analyzer:
+#   exclude:
+#     - path/to/excluded/files/**
+
+# For more information about the core and recommended set of lints, see
+# https://dart.dev/go/core-lints
+
+# For additional information about configuring this file, see
+# https://dart.dev/guides/language/analysis-options

objectbox/example/dart-native/vectorsearch_cities/bin/vectorsearch_cities.dart

@@ -0,0 +1,17 @@
+import 'package:vectorsearch_cities/objectbox.dart';
+
+void main(List<String> arguments) {
+  final objectBox = ObjectBox.create();
+
+  // Retrieve IDs
+  final resultIds = objectBox.findTwoClosestNeighborsIds();
+  for (final result in resultIds) {
+    print("City ID: ${result.id}, distance: ${result.score}");
+  }
+
+  // Retrieve objects
+  final results = objectBox.findTwoClosestNeighbors();
+  for (final result in results) {
+    print("City: ${result.object.name}, distance: ${result.score}");
+  }
+}

objectbox/example/dart-native/vectorsearch_cities/lib/model.dart

@@ -0,0 +1,15 @@
+import 'package:objectbox/objectbox.dart';
+
+@Entity()
+class City {
+  @Id()
+  int id = 0;
+
+  String? name;
+
+  @HnswIndex(dimensions: 2)
+  @Property(type: PropertyType.floatVector)
+  List<double>? location;
+
+  City(this.name, this.location);
+}

objectbox/example/dart-native/vectorsearch_cities/lib/objectbox-model.json

@@ -0,0 +1,44 @@
+{
+  "_note1": "KEEP THIS FILE! Check it into a version control system (VCS) like git.",
+  "_note2": "ObjectBox manages crucial IDs for your object model. See docs for details.",
+  "_note3": "If you have VCS merge conflicts, you must resolve them according to ObjectBox docs.",
+  "entities": [
+    {
+      "id": "1:4473667649417503248",
+      "lastPropertyId": "3:6086893156295683893",
+      "name": "City",
+      "properties": [
+        {
+          "id": "1:7234981322630746044",
+          "name": "id",
+          "type": 6,
+          "flags": 1
+        },
+        {
+          "id": "2:2260839727248414810",
+          "name": "name",
+          "type": 9
+        },
+        {
+          "id": "3:6086893156295683893",
+          "name": "location",
+          "type": 28,
+          "flags": 8,
+          "indexId": "1:145739237546482940"
+        }
+      ],
+      "relations": []
+    }
+  ],
+  "lastEntityId": "1:4473667649417503248",
+  "lastIndexId": "1:145739237546482940",
+  "lastRelationId": "0:0",
+  "lastSequenceId": "0:0",
+  "modelVersion": 5,
+  "modelVersionParserMinimum": 5,
+  "retiredEntityUids": [],
+  "retiredIndexUids": [],
+  "retiredPropertyUids": [],
+  "retiredRelationUids": [],
+  "version": 1
+}

objectbox/example/dart-native/vectorsearch_cities/lib/objectbox.dart

@@ -0,0 +1,69 @@
+import 'model.dart';
+import 'objectbox.g.dart';
+
+/// Provides access to the ObjectBox Store throughout the app.
+class ObjectBox {
+  /// The Store of this app.
+  late final Store _store;
+
+  late final Box<City> _cityBox;
+
+  ObjectBox._create(this._store) {
+    _cityBox = Box<City>(_store);
+
+    if (_cityBox.isEmpty()) {
+      _putCityData();
+    }
+  }
+
+  /// Create an instance of ObjectBox to use throughout the app.
+  static ObjectBox create() {
+    // Note: set macosApplicationGroup for sandboxed macOS applications, see the
+    // Store documentation for details.
+
+    // Store openStore() {...} is defined in the generated objectbox.g.dart
+    final store = openStore(
+        directory: "obx-demo-vectorsearch-cities",
+        macosApplicationGroup: "objectbox.demo");
+    return ObjectBox._create(store);
+  }
+
+  _putCityData() {
+    _cityBox.putMany([
+      City("Barcelona", [41.385063, 2.173404]),
+      City("Nairobi", [-1.292066, 36.821945]),
+      City("Salzburg", [47.809490, 13.055010]),
+    ]);
+  }
+
+  Query<City> _queryTwoClosestNeighbors() {
+    final madrid = [40.416775, -3.703790]; // query vector
+    // Prepare a Query object to search for the 2 closest neighbors:
+    final query =
+        _cityBox.query(City_.location.nearestNeighborsF32(madrid, 2)).build();
+
+    // Combine with other conditions as usual
+    // ignore: unused_local_variable
+    final queryCombined = _cityBox
+        .query(City_.location
+            .nearestNeighborsF32(madrid, 2)
+            .and(City_.name.startsWith("B")))
+        .build();
+
+    return query;
+  }
+
+  List<IdWithScore> findTwoClosestNeighborsIds() {
+    final query = _queryTwoClosestNeighbors();
+    final results = query.findIdsWithScores();
+    query.close();
+    return results;
+  }
+
+  List<ObjectWithScore<City>> findTwoClosestNeighbors() {
+    final query = _queryTwoClosestNeighbors();
+    final results = query.findWithScores();
+    query.close();
+    return results;
+  }
+}

objectbox/example/dart-native/vectorsearch_cities/pubspec.yaml

@@ -0,0 +1,21 @@
+name: vectorsearch_cities
+description: Vector Search Example with Cities.
+version: 1.0.0
+
+environment:
+  sdk: ^2.18.6
+
+dependencies:
+  objectbox: ^4.0.0
+
+dev_dependencies:
+  build_runner: ^2.4.9
+  lints: ^3.0.0
+  objectbox_generator: any
+
+# Note: these overrides are only for ObjectBox internal development, don't use them in your app.
+dependency_overrides:
+  objectbox:
+    path: ../../../../objectbox
+  objectbox_generator:
+    path: ../../../../generator

tool/init.sh

@@ -40,6 +40,7 @@ initialize dart objectbox
 initialize dart generator
 initialize dart objectbox_test generate
 initialize dart benchmark generate
+initialize dart objectbox/example/dart-native/vectorsearch_cities generate
 initialize flutter objectbox/example/flutter/objectbox_demo generate
 initialize flutter objectbox/example/flutter/objectbox_demo_relations generate
 initialize flutter objectbox/example/flutter/objectbox_demo_sync generate

tool/pubdev-links.sh

@@ -6,6 +6,7 @@ echo "Setting pub.dev specific links"
 update objectbox/README.md "s|CHANGELOG.md|https://pub.dev/packages/objectbox/changelog|g"
 update objectbox/README.md "s|../CONTRIBUTING.md|https://github.com/objectbox/objectbox-dart/blob/main/CONTRIBUTING.md|g"
 # Links generated by pub.dev are missing "objectbox" path, so replace with absolute link.
+update objectbox/example/README.md "s|dart-native/vectorsearch_cities|https://github.com/objectbox/objectbox-dart/tree/main/objectbox/example/dart-native/vectorsearch_cities|g"
 update objectbox/example/README.md "s|flutter/objectbox_demo|https://github.com/objectbox/objectbox-dart/tree/main/objectbox/example/flutter/objectbox_demo|g"
 #update objectbox/example/README.md "s|flutter/objectbox_demo_relations|https://github.com/objectbox/objectbox-dart/tree/main/objectbox/example/flutter/objectbox_demo_relations|g"
 update objectbox/example/README.md "s|flutter/event_management_tutorial|https://github.com/objectbox/objectbox-dart/tree/main/objectbox/example/flutter/event_management_tutorial|g"

tool/set-version.sh

@@ -21,6 +21,7 @@ versionDartExpr="s/current = \".*\"/current = \"${version}\"/g"
 update generator/lib/src/version.dart "${versionDartExpr}"
 
 dependencyHigherExpr="s/objectbox: \^.*/objectbox: ^${version}/g"
+update objectbox/example/dart-native/vectorsearch_cities/pubspec.yaml "${dependencyHigherExpr}"
 update objectbox/example/flutter/event_management_tutorial/event_manager/pubspec.yaml "${dependencyHigherExpr}"
 update objectbox/example/flutter/event_management_tutorial/many_to_many/pubspec.yaml "${dependencyHigherExpr}"
 update objectbox/example/flutter/objectbox_demo/pubspec.yaml "${dependencyHigherExpr}"