Check valid response construction

Author: KochTobi

project-management/src/main/java/life/qbic/projectmanagement/application/api/AsyncProjectService.java

@@ -1,5 +1,8 @@
 package life.qbic.projectmanagement.application.api;
 
+import static java.util.Objects.isNull;
+
+import java.util.Optional;
 import java.util.UUID;
 import reactor.core.publisher.Mono;
 
@@ -123,6 +126,41 @@ public String requestId() {
    */
   record ProjectUpdateResponse(String projectId, UpdateResponseBody responseBody, String requestId) {
 
+    public ProjectUpdateResponse {
+      if (projectId == null) {
+        throw new IllegalArgumentException("Project ID cannot be null");
+      }
+      if (projectId.isBlank()) {
+        throw new IllegalArgumentException("Project ID cannot be blank");
+      }
+      if (requestId != null && requestId.isBlank()) {
+        requestId = null;
+      }
+    }
+
+    /**
+     * Retrieves the request id associated with this response. May be {@link Optional#empty()} but
+     * never null.
+     *
+     * @return an Optional with the requestId; {@link Optional#empty()} otherwise.
+     */
+    public Optional<String> retrieveRequestId() {
+      return Optional.ofNullable(requestId);
+    }
+
+    /**
+     * Returns the requestId, if no requestId is set, returns an empty String.
+     *
+     * @return Returns the requestId, if no requestId is set, returns an empty String.
+     */
+    @Override
+    public String requestId() {
+      return isNull(requestId) ? "" : requestId;
+    }
+
+    boolean hasRequestId() {
+      return isNull(requestId);
+    }
   }
 
   /**