Transient field ignorer annotation

README.md

@@ -118,6 +118,19 @@ final qt = box.query(Entity_.text.notNull())
   .build();
 ```
 
+### Transient fields
+Fields that you *don't* wish to persist in objectbox, could be
+annotated with `@Transient`.
+
+```dart
+@Entity class k {
+  @Transient()
+  String ignoreThis;
+
+  //...
+}
+```
+
 Help wanted
 -----------
 ObjectBox for Dart is still in an early stage with limited feature set (compared to other languages).

example/README.md

@@ -14,6 +14,12 @@ class Note {
     int id;
     String text;
 
+    @Transient()
+    int these, fields, are, ignored;
+
+    @Transient()
+    String thisToo;
+
     Note({this.text}); // empty default constructor needed but it can have optional args
     toString() => "Note{id: $id, text: $text}";
 }

generator/lib/src/entity_resolver.dart

@@ -19,6 +19,7 @@ class EntityResolver extends Builder {
   final _annotationChecker = const TypeChecker.fromRuntime(obx.Entity);
   final _propertyChecker = const TypeChecker.fromRuntime(obx.Property);
   final _idChecker = const TypeChecker.fromRuntime(obx.Id);
+  final _transientChecker = const TypeChecker.fromRuntime(obx.Transient);
 
   @override
   FutureOr<void> build(BuildStep buildStep) async {
@@ -54,6 +55,12 @@ class EntityResolver extends Builder {
     // read all suitable annotated properties
     bool hasIdProperty = false;
     for (var f in element.fields) {
+
+      if (_transientChecker.hasAnnotationOfExact(f)) {
+        log.info("  skipping property ${f.name} (annotated with @Transient)");
+        continue;
+      }
+
       int fieldType, flags = 0;
       int propUid;
 

lib/src/annotations.dart

@@ -20,3 +20,7 @@ class Id {
   final int uid;
   const Id({this.uid});
 }
+
+class Transient {
+  const Transient();
+}

test/entity.dart

@@ -18,6 +18,12 @@ class TestEntity {
   double tDouble;
   bool tBool;
 
+  @Transient()
+  int ignore;
+
+  @Transient()
+  int omit, disregard;
+
   // explicitly declared types, see OB-C, objectbox.h
 
   // OBXPropertyType.Byte | 1 byte
@@ -50,5 +56,12 @@ class TestEntity {
       this.tShort,
       this.tChar,
       this.tInt,
-      this.tFloat});
+      this.tFloat,
+      this.ignore
+      });
+
+  TestEntity.ignoredExcept(this.tInt) {
+    this.omit = -1;
+    this.disregard = 1;
+  }
 }

test/query_test.dart

@@ -12,6 +12,37 @@ void main() {
     box = env.box;
   });
 
+  test("ignore transient field", () {
+    box.put(
+      TestEntity(tDouble: 0.1, ignore: 1337));
+
+    final d = TestEntity_.tDouble;
+
+    final q = box.query(d.between(0.0, 0.2)).build();
+
+    expect(q.count(), 1);
+    expect(q.findFirst().ignore, null);
+  });
+
+  test("ignore multiple transient fields", () {
+    final entity = TestEntity.ignoredExcept(1337);
+
+    box.put(entity);
+
+    expect(entity.omit, -1);
+    expect(entity.disregard, 1);
+
+    final i = TestEntity_.tInt;
+
+    final q = box.query(i.equals(1337)).build();
+
+    final result = q.findFirst();
+
+    expect(q.count(), 1);
+    expect(result.disregard, null);
+    expect(result.omit, null);
+  });
+
   test(".null and .notNull", () {
     box.putMany([
       TestEntity(tDouble: 0.1, tBool: true),