DATAREST-1248 - SortTranslator now considers read-only properties sortable.

MappedProperties now exposes a factory method that uses the Jackson introspector for serialization (instead of deserialization) which now also includes read-only properties. Previously, read-only ones were not considered as they are excluded from the metadata if it is looked up for deserialization.

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/json/DomainObjectReader.java

@@ -219,7 +219,7 @@ public class DomainObjectReader {
 			return mapper.readerForUpdating(target).readValue(root);
 		}
 
-		MappedProperties mappedProperties = MappedProperties.fromJacksonProperties(entity, mapper);
+		MappedProperties mappedProperties = MappedProperties.forDeserialization(entity, mapper);
 
 		for (Iterator<Entry<String, JsonNode>> i = root.fields(); i.hasNext();) {
 
@@ -616,7 +616,7 @@ public class DomainObjectReader {
 			Assert.notNull(entity, "PersistentEntity must not be null!");
 			Assert.notNull(mapper, "ObjectMapper must not be null!");
 
-			this.properties = MappedProperties.fromJacksonProperties(entity, mapper);
+			this.properties = MappedProperties.forDeserialization(entity, mapper);
 			this.targetAccessor = new ConvertingPropertyAccessor(entity.getPropertyAccessor(target),
 					new DefaultConversionService());
 			this.sourceAccessor = entity.getPropertyAccessor(source);

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/json/JacksonMappingAwareSortTranslator.java

@@ -226,7 +226,7 @@ public class JacksonMappingAwareSortTranslator {
 
 			if (persistentEntity != null) {
 
-				this.currentProperties = MappedProperties.fromJacksonProperties(currentType, objectMapper);
+				this.currentProperties = MappedProperties.forSerialization(currentType, objectMapper);
 				this.currentWrappedProperties = WrappedProperties.fromJacksonProperties(persistentEntities, currentType,
 						objectMapper);
 

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/json/MappedProperties.java

@@ -28,7 +28,9 @@ import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.util.Assert;
 
 import com.fasterxml.jackson.databind.BeanDescription;
+import com.fasterxml.jackson.databind.DeserializationConfig;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationConfig;
 import com.fasterxml.jackson.databind.introspect.BasicClassIntrospector;
 import com.fasterxml.jackson.databind.introspect.BeanPropertyDefinition;
 import com.fasterxml.jackson.databind.introspect.ClassIntrospector;
@@ -81,16 +83,34 @@ class MappedProperties {
 	}
 
 	/**
-	 * Creates {@link MappedProperties} for the given {@link PersistentEntity}.
+	 * Creates {@link MappedProperties} for the given {@link PersistentEntity} for deserialization purposes. Will not
+	 * include Jackson-read-only properties.
 	 *
 	 * @param entity must not be {@literal null}.
 	 * @param mapper must not be {@literal null}.
 	 * @return
 	 */
-	public static MappedProperties fromJacksonProperties(PersistentEntity<?, ?> entity, ObjectMapper mapper) {
+	public static MappedProperties forDeserialization(PersistentEntity<?, ?> entity, ObjectMapper mapper) {
 
-		BeanDescription description = INTROSPECTOR.forDeserialization(mapper.getDeserializationConfig(),
-				mapper.constructType(entity.getType()), mapper.getDeserializationConfig());
+		DeserializationConfig config = mapper.getDeserializationConfig();
+		BeanDescription description = INTROSPECTOR.forDeserialization(config, mapper.constructType(entity.getType()),
+				config);
+
+		return new MappedProperties(entity, description);
+	}
+
+	/**
+	 * Creates {@link MappedProperties} for the given {@link PersistentEntity} for serialization purposes. Includes
+	 * Jackson-read-only properties.
+	 *
+	 * @param entity must not be {@literal null}.
+	 * @param mapper must not be {@literal null}.
+	 * @return
+	 */
+	public static MappedProperties forSerialization(PersistentEntity<?, ?> entity, ObjectMapper mapper) {
+
+		SerializationConfig config = mapper.getSerializationConfig();
+		BeanDescription description = INTROSPECTOR.forSerialization(config, mapper.constructType(entity.getType()), config);
 
 		return new MappedProperties(entity, description);
 	}

spring-data-rest-webmvc/src/main/java/org/springframework/data/rest/webmvc/json/WrappedProperties.java

@@ -34,6 +34,7 @@ import com.fasterxml.jackson.annotation.JsonUnwrapped;
 import com.fasterxml.jackson.databind.AnnotationIntrospector;
 import com.fasterxml.jackson.databind.BeanDescription;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.SerializationConfig;
 import com.fasterxml.jackson.databind.introspect.AnnotatedMember;
 import com.fasterxml.jackson.databind.introspect.BasicClassIntrospector;
 import com.fasterxml.jackson.databind.introspect.BeanPropertyDefinition;
@@ -200,8 +201,10 @@ class WrappedProperties {
 		}
 
 		private BeanDescription getBeanDescription(Class<?> type) {
-			return INTROSPECTOR.forDeserialization(mapper.getDeserializationConfig(), mapper.constructType(type),
-					mapper.getDeserializationConfig());
+
+			SerializationConfig config = mapper.getSerializationConfig();
+
+			return INTROSPECTOR.forSerialization(config, mapper.constructType(type), config);
 		}
 
 		private static AnnotatedMember findAnnotatedMember(BeanPropertyDefinition property) {

spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/json/MappedPropertiesUnitTests.java

@@ -38,7 +38,7 @@ public class MappedPropertiesUnitTests {
 	ObjectMapper mapper = new ObjectMapper();
 	KeyValueMappingContext context = new KeyValueMappingContext();
 	KeyValuePersistentEntity<?> entity = context.getPersistentEntity(Sample.class);
-	MappedProperties properties = MappedProperties.fromJacksonProperties(entity, mapper);
+	MappedProperties properties = MappedProperties.forDeserialization(entity, mapper);
 
 	@Test // DATAREST-575
 	public void doesNotExposeMappedPropertyForNonSpringDataPersistentProperty() {
@@ -76,6 +76,15 @@ public class MappedPropertiesUnitTests {
 		assertThat(properties.getPersistentProperty("readOnlyProperty"), is(nullValue()));
 	}
 
+	@Test // DATAREST-1248
+	public void doesNotExcludeReadOnlyPropertiesForSerialization() {
+
+		MappedProperties properties = MappedProperties.forSerialization(entity, mapper);
+
+		assertThat(properties.hasPersistentPropertyForField("readOnlyProperty"), is(true));
+		assertThat(properties.getPersistentProperty("readOnlyProperty"), is(notNullValue()));
+	}
+
 	static class Sample {
 
 		public @Transient String notExposedBySpringData;

spring-data-rest-webmvc/src/test/java/org/springframework/data/rest/webmvc/json/SortTranslatorUnitTests.java

@@ -35,6 +35,7 @@ import org.springframework.data.rest.webmvc.json.JacksonMappingAwareSortTranslat
 import org.springframework.data.rest.webmvc.mapping.Associations;
 
 import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonProperty.Access;
 import com.fasterxml.jackson.annotation.JsonUnwrapped;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
@@ -172,12 +173,22 @@ public class SortTranslatorUnitTests {
 		assertThat(translatedSort.getOrderFor("burrito.embedded.name"), is(notNullValue()));
 	}
 
+	@Test // DATAREST-1248
+	public void allowsSortingByReadOnlyProperty() {
+
+		Sort sort = sortTranslator.translateSort(new Sort("readOnly"), mappingContext.getPersistentEntity(Plain.class));
+
+		assertThat(sort, is(notNullValue()));
+		assertThat(sort.getOrderFor("readOnly"), is(notNullValue()));
+	}
+
 	static class Plain {
 
 		public String name;
 		public Embedded embedded;
 		@Reference public Embedded refEmbedded;
 		@Reference public AnotherRootEntity association;
+		@JsonProperty(access = Access.READ_ONLY) public String readOnly;
 	}
 
 	static class UnwrapEmbedded {