Merge pull request #3553 from joschi/issue-3552

Support for overriding enum values with @JsonProperty or @JsonValue

Author: frantuma

modules/swagger-core/src/main/java/io/swagger/v3/core/jackson/ModelResolver.java

@@ -7,6 +7,7 @@
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonTypeInfo;
 import com.fasterxml.jackson.annotation.JsonUnwrapped;
+import com.fasterxml.jackson.annotation.JsonValue;
 import com.fasterxml.jackson.annotation.JsonView;
 import com.fasterxml.jackson.annotation.ObjectIdGenerator;
 import com.fasterxml.jackson.annotation.ObjectIdGenerators;
@@ -80,6 +81,7 @@
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -933,11 +935,29 @@ protected void _addEnumProps(Class<?> propClass, Schema property) {
         final boolean useIndex = _mapper.isEnabled(SerializationFeature.WRITE_ENUMS_USING_INDEX);
         final boolean useToString = _mapper.isEnabled(SerializationFeature.WRITE_ENUMS_USING_TO_STRING);
 
+
+        Optional<Method> jsonValueMethod = Arrays.stream(propClass.getMethods())
+                .filter(m -> m.isAnnotationPresent(JsonValue.class))
+                .filter(m -> m.getAnnotation(JsonValue.class).value())
+                .findFirst();
+
         @SuppressWarnings("unchecked")
         Class<Enum<?>> enumClass = (Class<Enum<?>>) propClass;
-        for (Enum<?> en : enumClass.getEnumConstants()) {
+
+        Enum<?>[] enumConstants = enumClass.getEnumConstants();
+        String[] enumValues = _intr.findEnumValues(propClass, enumConstants, new String[enumConstants.length]);
+
+        for (Enum<?> en : enumConstants) {
             String n;
-            if (useIndex) {
+
+            String enumValue = enumValues[en.ordinal()];
+            String s = jsonValueMethod.flatMap(m -> ReflectionUtils.safeInvoke(m, en)).map(Object::toString).orElse(null);
+
+            if (s != null) {
+                n = s;
+            } else if (enumValue != null) {
+                n = enumValue;
+            } else if (useIndex) {
                 n = String.valueOf(en.ordinal());
             } else if (useToString) {
                 n = en.toString();

modules/swagger-core/src/main/java/io/swagger/v3/core/util/ReflectionUtils.java

@@ -9,6 +9,7 @@
 import java.lang.annotation.Annotation;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.lang.reflect.Type;
@@ -17,6 +18,7 @@
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Optional;
 import java.util.Set;
 
 public class ReflectionUtils {
@@ -373,4 +375,13 @@ public static boolean isSystemType(JavaType type) {
         }
         return false;
     }
+
+    public static Optional<Object> safeInvoke(Method method, Object obj, Object... args) {
+        try {
+            return Optional.ofNullable(method.invoke(obj, args));
+        } catch (IllegalAccessException | InvocationTargetException e) {
+            return Optional.empty();
+        }
+
+    }
 }

modules/swagger-core/src/test/java/io/swagger/v3/core/converting/EnumPropertyTest.java

@@ -10,6 +10,7 @@
 import io.swagger.v3.core.oas.models.ModelWithEnumField;
 import io.swagger.v3.core.oas.models.ModelWithEnumProperty;
 import io.swagger.v3.core.oas.models.ModelWithEnumRefProperty;
+import io.swagger.v3.core.oas.models.ModelWithJacksonEnumField;
 import io.swagger.v3.oas.models.media.Schema;
 import io.swagger.v3.oas.models.media.StringSchema;
 import org.testng.annotations.AfterTest;
@@ -156,4 +157,25 @@ public void testEnumRefPropertyGlobalNotAffectingNonEnums() {
         SerializationMatchers.assertEqualsToYaml(models, yaml);
         ModelResolver.enumsAsRef = false;
     }
+
+    @Test(description = "it should extract enum values from fields using JsonProperty and JsonValue")
+    public void testExtractJacksonEnumFields() {
+        final Map<String, Schema> models = ModelConverters.getInstance().read(ModelWithJacksonEnumField.class);
+        final Schema model = models.get("ModelWithJacksonEnumField");
+
+        final Schema firstEnumProperty = (Schema) model.getProperties().get("firstEnumValue");
+        assertTrue(firstEnumProperty instanceof StringSchema);
+        final StringSchema stringProperty = (StringSchema) firstEnumProperty;
+        assertEquals(stringProperty.getEnum(), Arrays.asList("p1", "p2", "SYSTEM", "INVITE_ONLY"));
+
+        final Schema secondEnumProperty = (Schema) model.getProperties().get("secondEnumValue");
+        assertTrue(secondEnumProperty instanceof StringSchema);
+        final StringSchema secondStringProperty = (StringSchema) secondEnumProperty;
+        assertEquals(secondStringProperty.getEnum(), Arrays.asList("one", "two", "three"));
+
+        final Schema thirdEnumProperty = (Schema) model.getProperties().get("thirdEnumValue");
+        assertTrue(thirdEnumProperty instanceof StringSchema);
+        final StringSchema thirdStringProperty = (StringSchema) thirdEnumProperty;
+        assertEquals(thirdStringProperty.getEnum(), Arrays.asList("2", "4", "6"));
+    }
 }

modules/swagger-core/src/test/java/io/swagger/v3/core/oas/models/JacksonNumberValueEnum.java

@@ -0,0 +1,20 @@
+package io.swagger.v3.core.oas.models;
+
+import com.fasterxml.jackson.annotation.JsonValue;
+
+public enum JacksonNumberValueEnum {
+    FIRST(2),
+    SECOND(4),
+    THIRD(6);
+
+    private final int value;
+
+    JacksonNumberValueEnum(int value) {
+        this.value = value;
+    }
+
+    @JsonValue
+    public Number getValue() {
+        return value;
+    }
+}

modules/swagger-core/src/test/java/io/swagger/v3/core/oas/models/JacksonPropertyEnum.java

@@ -0,0 +1,10 @@
+package io.swagger.v3.core.oas.models;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public enum JacksonPropertyEnum {
+    @JsonProperty("p1") PRIVATE,
+    @JsonProperty("p2") PUBLIC,
+    SYSTEM,
+    INVITE_ONLY
+}

modules/swagger-core/src/test/java/io/swagger/v3/core/oas/models/JacksonValueEnum.java

@@ -0,0 +1,20 @@
+package io.swagger.v3.core.oas.models;
+
+import com.fasterxml.jackson.annotation.JsonValue;
+
+public enum JacksonValueEnum {
+    FIRST("one"),
+    SECOND("two"),
+    THIRD("three");
+
+    private final String value;
+
+    JacksonValueEnum(String value) {
+        this.value = value;
+    }
+
+    @JsonValue
+    public String getValue() {
+        return value;
+    }
+}

modules/swagger-core/src/test/java/io/swagger/v3/core/oas/models/ModelWithJacksonEnumField.java

@@ -0,0 +1,7 @@
+package io.swagger.v3.core.oas.models;
+
+public class ModelWithJacksonEnumField {
+    public JacksonPropertyEnum firstEnumValue;
+    public JacksonValueEnum secondEnumValue;
+    public JacksonNumberValueEnum thirdEnumValue;
+}