Fix controller test XMLMapper setup

Also add Kotlin serialization Jackson module.

Author: afranken

server/pom.xml

@@ -51,6 +51,11 @@
       <groupId>com.fasterxml.jackson.datatype</groupId>
       <artifactId>jackson-datatype-jdk8</artifactId>
     </dependency>
+    <dependency>
+      <groupId>com.fasterxml.jackson.module</groupId>
+      <artifactId>jackson-module-kotlin</artifactId>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>software.amazon.awssdk</groupId>
       <artifactId>regions</artifactId>

server/src/test/kotlin/com/adobe/testing/s3mock/BaseControllerTest.kt

@@ -20,23 +20,20 @@ import com.fasterxml.jackson.annotation.JsonInclude
 import com.fasterxml.jackson.dataformat.xml.XmlMapper
 import com.fasterxml.jackson.dataformat.xml.deser.FromXmlParser
 import com.fasterxml.jackson.dataformat.xml.ser.ToXmlGenerator
-import org.junit.jupiter.api.BeforeAll
 
 internal abstract class BaseControllerTest {
   companion object {
-    @JvmStatic
-    protected lateinit var MAPPER: XmlMapper
+    val MAPPER: XmlMapper = XmlMapper.builder()
+      .findAndAddModules()
+      .enable(ToXmlGenerator.Feature.WRITE_XML_DECLARATION)
+      .enable(ToXmlGenerator.Feature.AUTO_DETECT_XSI_TYPE)
+      .enable(FromXmlParser.Feature.AUTO_DETECT_XSI_TYPE)
+      .build()
 
-    @JvmStatic
-    @BeforeAll
-    fun setup() {
-      MAPPER = XmlMapper().enable(ToXmlGenerator.Feature.WRITE_XML_DECLARATION).apply {
-        this as XmlMapper
-        this.setSerializationInclusion(JsonInclude.Include.NON_EMPTY)
-        this.enable(ToXmlGenerator.Feature.AUTO_DETECT_XSI_TYPE)
-        this.enable(FromXmlParser.Feature.AUTO_DETECT_XSI_TYPE)
-        this.factory.xmlOutputFactory.setProperty(WstxOutputProperties.P_USE_DOUBLE_QUOTES_IN_XML_DECL, true)
-      } as XmlMapper
+    init {
+      MAPPER.setSerializationInclusion(JsonInclude.Include.NON_EMPTY)
+      MAPPER.factory.xmlOutputFactory
+        .setProperty(WstxOutputProperties.P_USE_DOUBLE_QUOTES_IN_XML_DECL, true)
     }
   }
 }