Fix RealmIdentifier XContent parser

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/security/authc/RealmConfig.java

@@ -267,7 +267,7 @@ public int compareTo(RealmIdentifier other) {
     );
 
     static {
-        REALM_IDENTIFIER_PARSER.declareString(constructorArg(), new ParseField("name"));
         REALM_IDENTIFIER_PARSER.declareString(constructorArg(), new ParseField("type"));
+        REALM_IDENTIFIER_PARSER.declareString(constructorArg(), new ParseField("name"));
     }
 }

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/security/authc/RealmConfigTests.java

@@ -11,10 +11,17 @@
 import org.elasticsearch.common.util.concurrent.ThreadContext;
 import org.elasticsearch.env.Environment;
 import org.elasticsearch.test.ESTestCase;
+import org.elasticsearch.xcontent.ToXContent;
+import org.elasticsearch.xcontent.XContentBuilder;
+import org.elasticsearch.xcontent.XContentFactory;
+import org.elasticsearch.xcontent.XContentParser;
 import org.junit.Before;
 import org.mockito.Mockito;
 
+import java.io.IOException;
+
 import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
 
 public class RealmConfigTests extends ESTestCase {
@@ -57,4 +64,13 @@ public void testWillNotFailWhenOrderIsMissingAndDisabled() {
         final RealmConfig realmConfig = new RealmConfig(realmIdentifier, settings, environment, threadContext);
         assertThat(realmConfig.enabled(), is(false));
     }
+
+    public void testXContentSerialization() throws IOException {
+        try (XContentBuilder builder = XContentFactory.jsonBuilder()) {
+            realmIdentifier.toXContent(builder, ToXContent.EMPTY_PARAMS);
+            try (XContentParser parser = createParser(builder)) {
+                assertThat(RealmConfig.REALM_IDENTIFIER_PARSER.parse(parser, null), equalTo(realmIdentifier));
+            }
+        }
+    }
 }

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/security/authc/RealmDomainTests.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+package org.elasticsearch.xpack.core.security.authc;
+
+import org.elasticsearch.common.io.stream.Writeable;
+import org.elasticsearch.test.AbstractSerializingTestCase;
+import org.elasticsearch.xcontent.XContentParser;
+
+import java.io.IOException;
+
+public class RealmDomainTests extends AbstractSerializingTestCase<RealmDomain> {
+
+    @Override
+    protected RealmDomain doParseInstance(XContentParser parser) throws IOException {
+        return RealmDomain.REALM_DOMAIN_PARSER.parse(parser, null);
+    }
+
+    @Override
+    protected Writeable.Reader<RealmDomain> instanceReader() {
+        return RealmDomain::readFrom;
+    }
+
+    @Override
+    protected RealmDomain createTestInstance() {
+        return AuthenticationTestHelper.randomDomain(randomBoolean());
+    }
+
+}