fix: read the OAS 3.1 type back for every schema subclass

CHANGELOG.md

@@ -32,6 +32,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - #3331 – Validation annotations declared inside `Optional` parameters are dropped
 - #3322 – Validation annotations on a container's type argument leak between parameters
 - #3315 – An OAS 3.1 `JsonSchema` cannot be cloned through JSON
+- #3314 – `Json Processing Exception occurred` is logged for every constrained parameter whose schema is not a `JsonSchema`
 - #3300 – TYPE_USE annotations on `@ParameterObject` fields are not passed along
 - #3341 – Stabilize Spring Data `Sort` and `Pageable` schema property order
 - #3338 – Kotlin nullability interpretation of the `Any?` type

springdoc-openapi-starter-common/src/main/java/org/springdoc/core/mixins/SchemaTypeMixin.java

@@ -30,15 +30,20 @@
 
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import io.swagger.v3.core.jackson.mixin.Schema31Mixin;
 import org.springdoc.core.deserializers.TypeSetDeserializer;
 
 /**
  * The type Schema type mixin. Makes the OpenAPI 3.1 {@code type} readable back into the
  * {@code types} set, whichever of the two serialized forms it takes.
+ * <p>
+ * It extends the swagger-core mixin so that it can be registered on {@code Schema} itself
+ * without losing the serialization it declares, which is what makes the deserializer apply
+ * to every schema subclass rather than to {@code JsonSchema} alone.
  *
  * @author Mattias-Sehlstedt
  */
-public interface SchemaTypeMixin {
+public abstract class SchemaTypeMixin extends Schema31Mixin {
 
 	/**
 	 * Sets types.
@@ -47,6 +52,6 @@ public interface SchemaTypeMixin {
 	 */
 	@JsonProperty("type")
 	@JsonDeserialize(using = TypeSetDeserializer.class)
-	void setTypes(Set<String> types);
+	public abstract void setTypes(Set<String> types);
 
 }

springdoc-openapi-starter-common/src/main/java/org/springdoc/core/mixins/SortedSchemaMixin31.java

@@ -36,8 +36,10 @@
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
 import com.fasterxml.jackson.databind.annotation.JsonSerialize;
 import io.swagger.v3.core.jackson.mixin.Schema31Mixin;
+import org.springdoc.core.deserializers.TypeSetDeserializer;
 
 /**
  * The interface Sorted schema mixin 31.
@@ -121,6 +123,15 @@ public interface SortedSchemaMixin31 {
 	@JsonSerialize(using = Schema31Mixin.TypeSerializer.class)
 	Set<String> getTypes();
 
+	/**
+	 * Sets types.
+	 *
+	 * @param types the types
+	 */
+	@JsonProperty("type")
+	@JsonDeserialize(using = TypeSetDeserializer.class)
+	void setTypes(Set<String> types);
+
 	/**
 	 * Add extension.
 	 *

springdoc-openapi-starter-common/src/main/java/org/springdoc/core/providers/ObjectMapperProvider.java

@@ -35,7 +35,6 @@
 import io.swagger.v3.core.util.Yaml;
 import io.swagger.v3.core.util.Yaml31;
 import io.swagger.v3.oas.models.OpenAPI;
-import io.swagger.v3.oas.models.media.JsonSchema;
 import io.swagger.v3.oas.models.media.Schema;
 import org.springdoc.core.mixins.SchemaTypeMixin;
 import org.springdoc.core.mixins.SortedOpenAPIMixin;
@@ -76,7 +75,7 @@ public ObjectMapperProvider(SpringDocConfigProperties springDocConfigProperties)
 		if (openApiVersion == OpenApiVersion.OPENAPI_3_1) {
 			jsonMapper = Json31.mapper();
 			yamlMapper = Yaml31.mapper();
-			jsonMapper.addMixIn(JsonSchema.class, SchemaTypeMixin.class);
+			jsonMapper.addMixIn(Schema.class, SchemaTypeMixin.class);
 			if (springDocConfigProperties.isUseArbitrarySchemas()) {
 				System.setProperty(Schema.USE_ARBITRARY_SCHEMA_PROPERTY, "true");
 			}
@@ -99,8 +98,10 @@ public ObjectMapperProvider(SpringDocConfigProperties springDocConfigProperties)
 	public static ObjectMapper createJson(SpringDocConfigProperties springDocConfigProperties) {
 		OpenApiVersion openApiVersion = springDocConfigProperties.getApiDocs().getVersion();
 		ObjectMapper objectMapper;
-		if (openApiVersion == OpenApiVersion.OPENAPI_3_1)
+		if (openApiVersion == OpenApiVersion.OPENAPI_3_1) {
 			objectMapper = ObjectMapperFactory.createJson31();
+			objectMapper.addMixIn(Schema.class, SchemaTypeMixin.class);
+		}
 		else
 			objectMapper = ObjectMapperFactory.createJson();
 

springdoc-openapi-starter-common/src/test/java/org/springdoc/core/utils/SpringDocUtilsTest.java

@@ -26,7 +26,9 @@
 
 import java.util.Set;
 
+import io.swagger.v3.oas.models.media.ArraySchema;
 import io.swagger.v3.oas.models.media.JsonSchema;
+import io.swagger.v3.oas.models.media.StringSchema;
 import org.junit.jupiter.api.Test;
 import org.springdoc.core.properties.SpringDocConfigProperties;
 import org.springdoc.core.properties.SpringDocConfigProperties.ApiDocs.OpenApiVersion;
@@ -90,10 +92,61 @@ void typeArrayIsRetainedForJsonSchemaJsonCloning() {
 		assertEquals(Set.of("integer", "null"), cloned.getTypes());
 	}
 
+	@Test
+	void singleTypeForSchemaSubclassJsonCloning() {
+		ObjectMapperProvider provider = openapi31Provider();
+
+		ArraySchema arraySchema = new ArraySchema();
+		arraySchema.setTypes(Set.of("array"));
+		arraySchema.setItems(new StringSchema());
+
+		ArraySchema cloned = SpringDocUtils.cloneViaJson(arraySchema, ArraySchema.class, provider.jsonMapper());
+
+		// The object is cloned properly, we do not get the type cast fallback
+		assertNotSame(arraySchema, cloned);
+		assertNotNull(cloned);
+		assertEquals(Set.of("array"), cloned.getTypes());
+	}
+
+	@Test
+	void singleTypeForSchemaSubclassJsonCloningWithAStandaloneMapper() {
+		ArraySchema arraySchema = new ArraySchema();
+		arraySchema.setTypes(Set.of("array"));
+		arraySchema.setItems(new StringSchema());
+
+		ArraySchema cloned = SpringDocUtils.cloneViaJson(arraySchema, ArraySchema.class, ObjectMapperProvider.createJson(openapi31Properties()));
+
+		// The object is cloned properly, we do not get the type cast fallback
+		assertNotSame(arraySchema, cloned);
+		assertNotNull(cloned);
+		assertEquals(Set.of("array"), cloned.getTypes());
+	}
+
+	@Test
+	void singleTypeForSchemaSubclassJsonCloningWithASortingMapper() {
+		SpringDocConfigProperties properties = openapi31Properties();
+		properties.setWriterWithOrderByKeys(true);
+
+		ArraySchema arraySchema = new ArraySchema();
+		arraySchema.setTypes(Set.of("array"));
+		arraySchema.setItems(new StringSchema());
+
+		ArraySchema cloned = SpringDocUtils.cloneViaJson(arraySchema, ArraySchema.class, ObjectMapperProvider.createJson(properties));
+
+		// The object is cloned properly, we do not get the type cast fallback
+		assertNotSame(arraySchema, cloned);
+		assertNotNull(cloned);
+		assertEquals(Set.of("array"), cloned.getTypes());
+	}
+
 	private ObjectMapperProvider openapi31Provider() {
+		return new ObjectMapperProvider(openapi31Properties());
+	}
+
+	private SpringDocConfigProperties openapi31Properties() {
 		SpringDocConfigProperties properties = new SpringDocConfigProperties();
 		properties.getApiDocs().setVersion(OpenApiVersion.OPENAPI_3_1);
-		return new ObjectMapperProvider(properties);
+		return properties;
 	}
 
 }