Fix/update imperative controller

api/synapse-api-rest-imperative/src/main/java/io/americanexpress/synapse/api/rest/imperative/controller/BaseUpdateImperativeRestController.java

@@ -1,12 +1,14 @@
 package io.americanexpress.synapse.api.rest.imperative.controller;
 
-import io.americanexpress.synapse.api.rest.imperative.controller.helpers.CreateResponseEntityCreator;
+import io.americanexpress.synapse.api.rest.imperative.controller.helpers.MonoResponseEntityCreator;
 import io.americanexpress.synapse.service.imperative.model.BaseServiceRequest;
 import io.americanexpress.synapse.service.imperative.model.BaseServiceResponse;
 import io.americanexpress.synapse.service.imperative.service.BaseService;
+import jakarta.validation.Valid;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestHeader;
 
 /**
@@ -30,10 +32,10 @@ public class BaseUpdateImperativeRestController<
      * @return response to the consumer
      */
     @PutMapping
-    public ResponseEntity<O> update(@RequestHeader HttpHeaders headers, I serviceRequest) {
+    public ResponseEntity<O> update(@RequestHeader HttpHeaders headers, @RequestBody @Valid I serviceRequest) {
         logger.entry(serviceRequest);
         O serviceResponse = service.execute(serviceRequest);
-        ResponseEntity<O> responseEntity = CreateResponseEntityCreator.create(serviceResponse);
+        ResponseEntity<O> responseEntity = MonoResponseEntityCreator.create(serviceResponse);
         logger.exit();
         return responseEntity;
     }

api/synapse-api-rest-imperative/src/main/java/io/americanexpress/synapse/api/rest/imperative/controller/healthcheck/HealthCheckController.java

@@ -31,7 +31,7 @@ public class HealthCheckController {
     /**
      * The health global Geographically Distributed High Availability (gdha) check endpoint.
      */
-    public static final String HEALTH_CHECK__GDHA_ENDPOINT = "/health-gdha";
+    public static final String HEALTH_CHECK_GDHA_ENDPOINT = "/health-gdha";
 
     /**
      * Health message used for the health check URIs.
@@ -52,7 +52,7 @@ public String healthCheck() {
      *
      * @return a constant message to notify that the service is receiving a request
      */
-    @GetMapping(HEALTH_CHECK__GDHA_ENDPOINT)
+    @GetMapping(HEALTH_CHECK_GDHA_ENDPOINT)
     public String healthGdhaCheck() {
         return HEALTH_MESSAGE;
     }

service/synapse-service-imperative/src/main/java/io/americanexpress/synapse/service/imperative/model/NullServiceResponse.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2020 American Express Travel Related Services Company, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package io.americanexpress.synapse.service.imperative.model;
+
+/**
+ * {@code NullServiceResponse} is used whenever a null response is required from a service. The service can just return
+ * NullServiceResponse.INSTANCE rather than just returning null directly as this class also extends {@code BaseServiceResponse}
+ * adhering to the prototype contracts.
+ */
+public class NullServiceResponse implements BaseServiceResponse {
+
+    /**
+     * Returns a null instance as a singleton pattern for when a null response is required from the service.
+     */
+    public static final NullServiceResponse INSTANCE = null;
+
+    /**
+     * Private constructor to prevent multiple instances being made.
+     */
+    private NullServiceResponse() {
+
+    }
+}