Support adding custom annotations for conversion

CHANGELOG.md

@@ -6,6 +6,7 @@
 ### Added
 - Added unknown_enum_value support
 - Added non_final support
+- Added support for json_converter
 
 ## [2.3.0] - 2020-10-04
 ### Added

README.md

@@ -34,6 +34,8 @@ Example of the `model_generator/config.yaml` file
 ```
 UserModel:
   path: webservice/user
+  converters:
+    - DateTimeConverter
   properties:
     id:
       type: int
@@ -69,9 +71,11 @@ UserModel:
     mutableField:
       non_final: true #Field will not be marked final
       type: string
+    changedAt:
+      type: datetime
 
 Address:
-  path: webservice/user
+  path: webservice/user #Can also be package:... and/or end with the actual file (.dart)
   properties:
     street:
       type: string
@@ -83,6 +87,12 @@ CustomBaseDirectoryObject:
   properties:
     path:
       type: string
+
+#Custom json converter. Use with converters property on models
+DateTimeConverter:
+  type: json_converter
+  path: converter/
+
 ```
 
 ## Enum support
@@ -141,4 +151,22 @@ CustomObjectFromToJson:
 {Model_Name} handle{Model_Name}FromJson(object) => {Model_Name}.fromJson(object);
 
 {Original_Type} handle{Model_Name}ToJson({Model_Name} data) => data.toJson();
-```
+```
+
+## JsonConverter support
+You can specify custom json converters to be used for types that match
+```
+UserModel:
+  path: webservice/user
+  converters:
+    - DateTimeConverter
+  properties:
+    changedAt:
+      type: datetime
+```
+Specify the custom JsonConverter object as a known type to resolve it
+```
+DateTimeConverter:
+  type: json_converter
+  path: converter/
+```

bin/model_generator.dart

@@ -1,12 +1,13 @@
 import 'dart:io';
 
-import 'package:path/path.dart';
 import 'package:meta/meta.dart';
+import 'package:path/path.dart';
 
 import 'src/config/pubspec_config.dart';
 import 'src/config/yml_generator_config.dart';
 import 'src/model/model/custom_model.dart';
 import 'src/model/model/enum_model.dart';
+import 'src/model/model/json_converter_model.dart';
 import 'src/model/object_model.dart';
 import 'src/writer/enum_model_writer.dart';
 import 'src/writer/object_model_writer.dart';
@@ -44,9 +45,12 @@ void writeToFiles(
     }
     String content;
     if (model is ObjectModel) {
-      content = ObjectModelWriter(pubspecConfig, model).write();
+      content =
+          ObjectModelWriter(pubspecConfig, model, modelGeneratorConfig).write();
     } else if (model is EnumModel) {
       content = EnumModelWriter(model).write();
+    } else if (model is JsonConverterModel) {
+      return;
     }
     if (model is! CustomModel && content == null) {
       throw Exception(

bin/src/config/yml_generator_config.dart

@@ -13,6 +13,7 @@ import '../model/item_type/string_type.dart';
 import '../model/model/custom_from_to_json_model.dart';
 import '../model/model/custom_model.dart';
 import '../model/model/enum_model.dart';
+import '../model/model/json_converter_model.dart';
 import '../model/model/model.dart';
 import '../model/object_model.dart';
 import '../util/type_checker.dart';
@@ -29,14 +30,17 @@ class YmlGeneratorConfig {
           value['base_directory'] ?? pubspecConfig.baseDirectory;
       final String path = value['path'];
       final YamlMap properties = value['properties'];
+      final YamlList converters = value['converters'];
       final String type = value['type'];
       if (type == 'custom') {
         models.add(CustomModel(key, path, baseDirectory));
         return;
-      }
-      if (type == 'custom_from_to_json') {
+      } else if (type == 'custom_from_to_json') {
         models.add(CustomFromToJsonModel(key, path, baseDirectory));
         return;
+      } else if (type == 'json_converter') {
+        models.add(JsonConverterModel(key, path, baseDirectory));
+        return;
       }
       if (properties == null) {
         throw Exception('Properties can not be null. model: $key');
@@ -59,12 +63,15 @@ class YmlGeneratorConfig {
           }
           fields.add(getField(propertyKey, propertyValue));
         });
-        models.add(ObjectModel(key, path, baseDirectory, fields));
+        final mappedConverters =
+            converters?.map((element) => element.toString())?.toList() ??
+                <String>[];
+        models.add(
+            ObjectModel(key, path, baseDirectory, fields, mappedConverters));
       }
     });
 
     checkIfTypesAvailable();
-    addPathsToFields(pubspecConfig);
   }
 
   Field getField(String name, YamlMap property) {
@@ -135,25 +142,21 @@ class YmlGeneratorConfig {
     }
   }
 
-  void addPathsToFields(PubspecConfig pubspecConfig) {
-    models.forEach((model) {
-      if (model is ObjectModel) {
-        model.fields.forEach((field) {
-          final foundModels =
-              models.where((model) => model.name == field.type.name).toList();
-          if (foundModels.isNotEmpty) {
-            final foundModel = foundModels[0];
-            final baseDirectory =
-                foundModel.baseDirectory ?? pubspecConfig.baseDirectory;
-            if (foundModel.path == null) {
-              field.path = '$baseDirectory';
-            } else {
-              field.path = '$baseDirectory/${foundModel.path}';
-            }
-          }
-        });
-      } else if (model is EnumModel) {}
-    });
+  String getPathForField(PubspecConfig pubspecConfig, Field field) {
+    return getPathForName(pubspecConfig, field.type.name);
+  }
+
+  String getPathForName(PubspecConfig pubspecConfig, String name) {
+    final foundModel =
+        models.firstWhere((model) => model.name == name, orElse: () => null);
+    if (foundModel == null) return null;
+    final baseDirectory =
+        foundModel.baseDirectory ?? pubspecConfig.baseDirectory;
+    if (foundModel.path == null) {
+      return '$baseDirectory';
+    } else {
+      return '$baseDirectory/${foundModel.path}';
+    }
   }
 
   void checkIfTypesAvailable() {

bin/src/model/field.dart

@@ -12,18 +12,6 @@ class Field {
   final bool nonFinal;
   final String unknownEnumValue;
 
-  String _path;
-
-  set path(String path) {
-    if (path != null && path.endsWith('/')) {
-      _path = path.substring(0, path.length - 1);
-    } else {
-      _path = path;
-    }
-  }
-
-  String get path => _path;
-
   Field(
       {String name,
       this.type,

bin/src/model/model/json_converter_model.dart

@@ -0,0 +1,9 @@
+import 'model.dart';
+
+class JsonConverterModel extends Model {
+  JsonConverterModel(
+    String name,
+    String path,
+    String baseDirectory,
+  ) : super(name, path, baseDirectory);
+}

bin/src/model/object_model.dart

@@ -3,11 +3,13 @@ import 'model/model.dart';
 
 class ObjectModel extends Model {
   final List<Field> fields;
+  final List<String> converters;
 
   ObjectModel(
     String name,
     String path,
     String baseDirectory,
     this.fields,
+    this.converters,
   ) : super(name, path, baseDirectory);
 }

bin/src/writer/object_model_writer.dart

@@ -9,44 +9,43 @@ import '../util/type_checker.dart';
 class ObjectModelWriter {
   final PubspecConfig pubspecConfig;
   final ObjectModel jsonModel;
+  final YmlGeneratorConfig yamlConfig;
 
-  const ObjectModelWriter(this.pubspecConfig, this.jsonModel);
+  const ObjectModelWriter(this.pubspecConfig, this.jsonModel, this.yamlConfig);
 
   String write() {
     final sb = StringBuffer();
+    final imports = Set<String>(); // ignore: prefer_collection_literals
 
     final containsRequiredFields =
         jsonModel.fields.where((item) => item.required).toList().isNotEmpty;
     if (containsRequiredFields) {
-      sb.writeln("import 'package:flutter/material.dart';");
+      imports.add("import 'package:flutter/material.dart';");
     }
 
-    sb.writeln("import 'package:json_annotation/json_annotation.dart';");
+    imports.add("import 'package:json_annotation/json_annotation.dart';");
 
-    final projectName = pubspecConfig.projectName;
     jsonModel.fields.forEach((field) {
       if (!TypeChecker.isKnownDartType(field.type.name)) {
-        final reCaseFieldName = CaseUtil(field.type.name);
-        String import;
-        if (field.path == null) {
-          import =
-              "import 'package:$projectName/${jsonModel.baseDirectory}/${reCaseFieldName.snakeCase}.dart';";
-        } else {
-          import =
-              "import 'package:$projectName/${field.path}/${reCaseFieldName.snakeCase}.dart';";
-        }
-        if (!sb.toString().contains(import)) {
-          sb.writeln(import);
-        }
+        imports.add(_getImportFromPath(field.type.name));
       }
     });
+    jsonModel.converters.forEach((converter) {
+      imports.add(_getImportFromPath(converter));
+    });
+    imports.forEach(sb.writeln);
 
     sb
       ..writeln()
       ..writeln("part '${jsonModel.fileName}.g.dart';")
       ..writeln()
-      ..writeln('@JsonSerializable()')
-      ..writeln('class ${jsonModel.name} {');
+      ..writeln('@JsonSerializable()');
+
+    jsonModel.converters.forEach((converter) {
+      sb.writeln('@$converter()');
+    });
+
+    sb.writeln('class ${jsonModel.name} {');
 
     jsonModel.fields.sort((a, b) {
       final b1 = a.required ? 1 : 0;
@@ -116,4 +115,26 @@ class ObjectModelWriter {
       ..writeln('}');
     return sb.toString();
   }
+
+  String _getImportFromPath(String name) {
+    final projectName = pubspecConfig.projectName;
+    final reCaseFieldName = CaseUtil(name);
+    final path = yamlConfig.getPathForName(pubspecConfig, name);
+    if (path == null) {
+      return "import 'package:$projectName/${jsonModel.baseDirectory}/${reCaseFieldName.snakeCase}.dart';";
+    }
+
+    String pathWithPackage;
+    if (path.startsWith('package:')) {
+      pathWithPackage = path;
+    } else {
+      pathWithPackage = 'package:$projectName/$path';
+    }
+
+    if (path.endsWith('.dart')) {
+      return "import '$pathWithPackage';";
+    } else {
+      return "import '$pathWithPackage/${reCaseFieldName.snakeCase}.dart';";
+    }
+  }
 }

example/lib/model/converter/date_time_converter.dart

@@ -0,0 +1,17 @@
+import 'package:json_annotation/json_annotation.dart';
+
+class DateTimeConverter implements JsonConverter<DateTime, String> {
+  const DateTimeConverter();
+
+  @override
+  DateTime fromJson(String json) {
+    var actualJson = json;
+    if (json.contains('.')) {
+      actualJson = json.substring(0, json.length - 1);
+    }
+    return DateTime.parse(actualJson);
+  }
+
+  @override
+  String toJson(DateTime json) => json.toIso8601String();
+}

example/lib/model/ogm.dart

@@ -1,9 +1,11 @@
 import 'package:flutter/material.dart';
 import 'package:json_annotation/json_annotation.dart';
+import 'package:model_generator_example/model/converter/date_time_converter.dart';
 
 part 'ogm.g.dart';
 
 @JsonSerializable()
+@DateTimeConverter()
 class OGM {
   @JsonKey(name: 'structuredMessage', required: true)
   final String structuredMessage;
@@ -21,6 +23,8 @@ class OGM {
   final String securityRole;
   @JsonKey(name: 'mutableProperty', nullable: true)
   String mutableProperty;
+  @JsonKey(name: 'dateChange', nullable: true)
+  final DateTime dateChange;
 
   OGM({
     @required this.structuredMessage,
@@ -31,6 +35,7 @@ class OGM {
     @required this.someThinGHuGE,
     this.securityRole,
     this.mutableProperty,
+    this.dateChange,
   });
 
   factory OGM.fromJson(Map<String, dynamic> json) => _$OGMFromJson(json);