Fix subtypes without properties (#622)

micronaut-projects · Oct 27, 2023 · bf0573e · bf0573e
1 parent ef025fc
commit bf0573e
Show file tree

Hide file tree

Showing 2 changed files with 48 additions and 3 deletions.
diff --git a/serde-jackson/src/test/groovy/io/micronaut/serde/jackson/annotation/JsonTypeInfoSpec.groovy b/serde-jackson/src/test/groovy/io/micronaut/serde/jackson/annotation/JsonTypeInfoSpec.groovy
@@ -770,4 +770,47 @@ record TypeA (String a, InterfaceB b) { }
         cleanup:
         context.close()
     }
+
+    void "test no properties subtype"() {
+        given:
+        def context = buildContext("""
+package subtypes;
+
+import com.fasterxml.jackson.annotation.*;
+import io.micronaut.core.annotation.Introspected;
+import io.micronaut.serde.annotation.Serdeable;
+
+@JsonTypeInfo(
+        use = JsonTypeInfo.Id.NAME,
+        property = "validation-type")
+@JsonSubTypes({
+        @JsonSubTypes.Type(value = NonEmptyString.class, name = "NonEmptyString"),
+})
+interface Validator { }
+
+@Serdeable
+class NonEmptyString implements Validator {
+ }
+""")
+
+        def argument = argumentOf(context, 'subtypes.NonEmptyString')
+
+        when:
+        def bean = newInstance(context, 'subtypes.NonEmptyString')
+        def json = writeJson(jsonMapper, bean)
+
+        then:
+        json == """{"validation-type":"NonEmptyString"}"""
+
+
+        when:
+        def deser = jsonMapper.readValue(json, argument)
+
+        then:
+        deser
+        argument.isInstance(deser)
+
+        cleanup:
+        context.close()
+    }
 }
diff --git a/serde-support/src/main/java/io/micronaut/serde/support/serializers/SerBean.java b/serde-support/src/main/java/io/micronaut/serde/support/serializers/SerBean.java
@@ -181,10 +181,12 @@ public int getOrder() {
                     initializers.add(ctx -> initProperty(ag, ctx));
                 }
 
-                if (!properties.isEmpty() || !jsonGetters.isEmpty()) {
+                AnnotationMetadata am = new AnnotationMetadataHierarchy(introspection, definition.getAnnotationMetadata());
+                Optional<String> subType = am.stringValue(SerdeConfig.class, SerdeConfig.TYPE_NAME);
+
+                if (!properties.isEmpty() || !jsonGetters.isEmpty() || subType.isPresent()) {
                     writeProperties = new ArrayList<>(properties.size() + jsonGetters.size());
-                    AnnotationMetadata am = new AnnotationMetadataHierarchy(introspection, definition.getAnnotationMetadata());
-                    am.stringValue(SerdeConfig.class, SerdeConfig.TYPE_NAME).ifPresent(typeName -> {
+                    subType.ifPresent(typeName -> {
                         String typeProperty = am.stringValue(SerdeConfig.class, SerdeConfig.TYPE_PROPERTY).orElse(null);
                         if (typeProperty != null) {
                             SerProperty<T, String> prop;