Fix deserialization if subtype discriminator is missing

Author: jenschude

commercetools/commercetools-sdk-java-api/src/test/java/com/commercetools/CartDiscountTest.java

@@ -4,7 +4,11 @@
 import static org.assertj.core.api.Assertions.assertThat;
 
 import com.commercetools.api.models.cart_discount.*;
+import com.commercetools.api.models.common.ReferenceTypeId;
 
+import io.vrap.rmf.base.client.utils.json.JsonUtils;
+
+import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 
 public class CartDiscountTest {
@@ -94,4 +98,17 @@ public void giftLineItemValueToDraft() {
             });
 
     }
+
+    @Test
+    public void deserializeGiftLineItemWithoutTypeId() {
+        String json = "{\"value\": { \"type\": \"giftLineItem\", \"product\": { \"id\": \"foo\" } } }";
+        CartDiscount cartDiscount = JsonUtils.fromJsonString(json, CartDiscount.class);
+        Assertions.assertThat(cartDiscount.getValue())
+                .isInstanceOfSatisfying(CartDiscountValueGiftLineItem.class, cartDiscountValueGiftLineItem -> {
+                    assertThat(cartDiscountValueGiftLineItem.getProduct().getId()).isEqualTo("foo");
+                    assertThat(cartDiscountValueGiftLineItem.getProduct().getTypeId())
+                            .isEqualTo(ReferenceTypeId.PRODUCT);
+                });
+        Assertions.assertThat(cartDiscount.getValue()).isInstanceOf(CartDiscountValueGiftLineItem.class);
+    }
 }

rmf/rmf-java-base/src/main/java/io/vrap/rmf/base/client/utils/json/JsonUtils.java

@@ -11,6 +11,7 @@
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.ObjectNode;
@@ -52,17 +53,19 @@ public static ObjectMapper createObjectMapper(final ModuleOptions options) {
         final List<SimpleModule> moduleList = new ArrayList<>();
         suppliers.iterator().forEachRemaining(moduleSupplier -> moduleList.add(moduleSupplier.getModule(options)));
 
-        final ObjectMapper objectMapper = new ObjectMapper();
-        objectMapper.registerModule(new JavaTimeModule()) //provides serialization and deserialization for LocalDate and LocalTime (JSR310 Jackson module)
-                .registerModule(new ZonedDateTimeSerializationModule()) //custom serializer for LocalDate, LocalTime and ZonedDateTime
-                .registerModule(new ZonedDateTimeDeserializationModule()) //custom deserializer for ZonedDateTime
-                .registerModule(new LocalDateDeserializationModule()) //custom deserializer for LocalDate
-                .registerModules(loader)
-                .registerModules(moduleList)
-                .setSerializationInclusion(JsonInclude.Include.NON_NULL) //ignore null fields
+        return JsonMapper.builder()
+                .configure(MapperFeature.REQUIRE_TYPE_ID_FOR_SUBTYPES, false)
                 .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
-                .configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
-        return objectMapper;
+                .configure(DeserializationFeature.FAIL_ON_MISSING_EXTERNAL_TYPE_ID_PROPERTY, false)
+                .configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false)
+                .serializationInclusion(JsonInclude.Include.NON_NULL)
+                .addModule(new JavaTimeModule())
+                .addModule(new ZonedDateTimeSerializationModule()) //custom serializer for LocalDate, LocalTime and ZonedDateTime
+                .addModule(new ZonedDateTimeDeserializationModule()) //custom deserializer for ZonedDateTime
+                .addModule(new LocalDateDeserializationModule()) //custom deserializer for LocalDate
+                .addModules(loader)
+                .addModules(moduleList)
+                .build();
     }
 
     /**