Add support for constructors, private variables and getters

README.md

@@ -59,6 +59,10 @@ import 'my_class.dart';
 final Dartson<String> serializer = _serializer$dartson.useCodec(json);
 ```
 
+### Private properties
+
+It's not possible to encode / decode private properties. To set private properties, expose these within the constructor
+and provide a getter for encoding the entity.
 
 ### Encoding / decoding lists
 

changelog.md

@@ -2,6 +2,11 @@
 
 ## 1.0.0-alpha+3
 
+- Add support for final properties
+- Add support to skip private properties
+- Add support for constructor arguments
+- Add support for getters
+
 **Breaking changes**
 - `DateTimeParser` is deprecated. The default is now the `json_serializable` implementation and it's no longer necessary
   to register a transformer at all.

lib/src/generator/entity_generator.dart

@@ -6,6 +6,7 @@ import 'package:json_serializable/src/type_helpers/enum_helper.dart';
 import 'package:json_serializable/src/type_helpers/iterable_helper.dart';
 import 'package:json_serializable/src/type_helpers/map_helper.dart';
 
+import '../annotations.dart';
 import 'entity_type_helper.dart';
 import 'field_context.dart';
 import 'identifier.dart';
@@ -47,8 +48,9 @@ class EntityGenerator {
           .newInstance([]).assignFinal('obj'));
 
     for (var field in _fields) {
-      final fieldProperty = propertyAnnotation(field);
-      if (fieldProperty.ignore) {
+      final fieldProperty = propertyAnnotation(
+          field.getter.metadata.isNotEmpty ? field.getter : field);
+      if (field.isPrivate || fieldProperty.ignore) {
         continue;
       }
 
@@ -78,12 +80,59 @@ class EntityGenerator {
   }
 
   Method _buildDecoder() {
+    final constructorParameters = <Expression>[];
+    final constructorNamedParameters = <String, Expression>{};
+    final passedConstructorParameters = <String>[];
+
+    // Get constructor arguments.
+    final constructorArguments = _element.constructors?.first?.parameters ?? [];
+    for (var field in constructorArguments) {
+      Property fieldProperty;
+      if (field.isInitializingFormal) {
+        // Fetch details from matching field.
+        fieldProperty = propertyAnnotation(
+            _fields.firstWhere((fe) => fe.name == field.name));
+
+        passedConstructorParameters.add(field.displayName);
+      } else {
+        // Check for annotations.
+        fieldProperty = propertyAnnotation(field);
+      }
+
+      if (fieldProperty.ignore && field.isNotOptional) {
+        // TODO: Throw proper error.
+        throw 'NotOptional marked as ignored';
+      }
+
+      if (fieldProperty.ignore) {
+        continue;
+      }
+
+      final fieldContext = FieldContext(true, field.metadata, _helpers);
+      _fieldContexts.add(fieldContext);
+
+      final expression = CodeExpression(Code(fieldContext.deserialize(
+          field.type, 'data[\'${fieldProperty.name ?? field.displayName}\']')));
+      if (field.isPositional) {
+        constructorParameters.add(expression);
+      } else {
+        constructorNamedParameters[field.name] = expression;
+      }
+    }
+
     final block = BlockBuilder()
       ..statements.add(Code('if (data == null) { return null; }'))
-      ..addExpression(
-          refer(_element.displayName).newInstance([]).assignFinal('obj'));
+      ..addExpression(refer(_element.displayName)
+          .newInstance(constructorParameters, constructorNamedParameters)
+          .assignFinal('obj'));
 
     for (var field in _fields) {
+      if (field.isFinal ||
+          passedConstructorParameters.contains(field.name) ||
+          field.isPrivate) {
+        continue;
+      }
+
       final fieldProperty = propertyAnnotation(field);
       if (fieldProperty.ignore) {
         continue;

lib/src/generator/utils.dart

@@ -3,7 +3,7 @@ import 'package:analyzer/src/dart/resolver/inheritance_manager.dart';
 import 'package:source_gen/source_gen.dart';
 import 'package:dartson/dartson.dart';
 
-Property propertyAnnotation(FieldElement element) {
+Property propertyAnnotation(Element element) {
   final annotations = TypeChecker.fromRuntime(Property).annotationsOf(element);
   if (annotations.isEmpty) {
     return Property();

test/dartson_test.dart

@@ -32,7 +32,7 @@ void main() {
     });
 
     test('should encode the object', () {
-      final result = serializer.encode(MyClass()
+      final result = serializer.encode(MyClass('test')
         ..name = 'hello'
         ..numDouble = 1.0
         ..subClass = (SubClass()..name = 'test'));
@@ -53,7 +53,7 @@ void main() {
     });
 
     test('should encode lists', () {
-      final result = serializer.encode(MyClass()
+      final result = serializer.encode(MyClass('test')
         ..subClasses = [
           SubClass()
             ..name = '1'
@@ -91,7 +91,7 @@ void main() {
     });
 
     test('should encode maps', () {
-      final result = serializer.encode(MyClass()
+      final result = serializer.encode(MyClass('test')
         ..complexMap = {
           't1': SubClass()..name = 't1',
           't2': SubClass()..name = 't2',
@@ -116,8 +116,8 @@ void main() {
     });
 
     test('should encode replacements', () {
-      final result =
-          serializer.encode(MyClass()..replacement = (MyImpl()..name = 'test'));
+      final result = serializer
+          .encode(MyClass('test')..replacement = (MyImpl()..name = 'test'));
       expect(result['replacement']['name'], 'test');
     });
 
@@ -161,8 +161,8 @@ void main() {
 
     test('should encode lists', () {
       final result = serializer.encodeList([
-        MyClass()..name = 'test1',
-        MyClass()..name = 'test2',
+        MyClass('test')..name = 'test1',
+        MyClass('test')..name = 'test2',
       ]) as List<Map<String, dynamic>>;
 
       expect(result, allOf(isList, hasLength(2)));

test/src/my_class.dart

@@ -7,6 +7,7 @@ enum MyEnum { firstValue, secondValue }
 enum SecondEnum { has, nothing }
 
 class MyClass extends BaseClass {
+  final String finalProp;
   String name;
   int number;
   @Property(name: 'boolean')
@@ -22,6 +23,14 @@ class MyClass extends BaseClass {
   List<SubClass> subClasses;
   Map<String, SubClass> complexMap;
   MyAbstr replacement;
+  String _private;
+
+  MyClass(this.finalProp,
+      {this.ignored, @Property(name: 'private') String renamedPrivate})
+      : _private = renamedPrivate;
+
+  @Property(name: 'private')
+  String get privateGetter => _private;
 }
 
 class BaseClass {

test/src/usage.dart

@@ -2,7 +2,7 @@ import 'serializer.dart';
 import 'my_class.dart';
 
 void usage() {
-  final myClass = MyClass()
+  final myClass = MyClass('test')
     ..name = 'test name'
     ..number = 29
     ..hasBoolean = true;