Merge with master

README.md

@@ -19,8 +19,7 @@
 
 **News**  
 
-- Hey, meet the new oatpp version `1.2.5`! See the [changelog](changelog/1.2.5.md) for details.  
-- Check out the new oatpp ORM - read more [here](https://oatpp.io/docs/components/orm/).  
+- Hey, the new oatpp version `1.3.0` will soon be merged to master! Follow the [changelog](https://github.com/oatpp/oatpp/blob/v1.3.0/changelog/1.3.0.md) for details, and prepare for migration. *[Follow PR](https://github.com/oatpp/oatpp/pull/453)*.
 
 ---
 

src/oatpp-test/UnitTest.hpp

@@ -27,6 +27,7 @@
 
 #include <functional>
 #include "oatpp/core/base/Environment.hpp"
+#include "oatpp/core/macro/basic.hpp"
 
 namespace oatpp { namespace test {
 
@@ -92,8 +93,10 @@ public:
 
 #define OATPP_RUN_TEST_0(TEST) \
 oatpp::test::UnitTest::runTest<TEST>(1)
+
 #define OATPP_RUN_TEST_1(TEST, N) \
 oatpp::test::UnitTest::runTest<TEST>(N)
+
 /**
  * Convenience macro to run test. <br>
  * Usage Example:<br>

src/oatpp/parser/json/mapping/Serializer.cpp

@@ -155,11 +155,12 @@ void Serializer::serializeObject(Serializer* serializer,
   );
   auto fields = dispatcher->getProperties()->getList();
   auto object = static_cast<oatpp::BaseObject*>(polymorph.get());
+  auto config = serializer->m_config;
 
   for (auto const& field : fields) {
 
     auto value = field->get(object);
-    if(value || serializer->m_config->includeNullFields) {
+    if (value || config->includeNullFields || (field->info.required && config->alwaysIncludeRequired)) {
       (first) ? first = false : stream->writeSimple(",", 1);
       serializeString(stream, field->name, std::strlen(field->name), serializer->m_config->escapeFlags);
       stream->writeSimple(":", 1);

src/oatpp/parser/json/mapping/Serializer.hpp

@@ -66,9 +66,15 @@ public:
 
     /**
      * Include fields with value == nullptr into serialized json.
+     * Field will still be included when field-info `required` is set to true and &id:alwaysIncludeRequired is set to true.
      */
     bool includeNullFields = true;
 
+    /**
+     * Always include required fields (set in in DTO_FIELD_INFO) even if they are `value == nullptr`
+     */
+    bool alwaysIncludeRequired = false;
+
     /**
      * If `true` - insert string `"<unknown-type>"` in json field value in case unknown field found.
      * Fail if `false`.