check if grant exists in dmp/dataset elastic entities

dmp-backend/elastic/src/main/java/eu/eudat/elastic/entities/Dataset.java

@@ -231,7 +231,9 @@ public class Dataset implements ElasticEntity<Dataset> {
         if (this.group != null) {
             builder.field("group", this.group.toString());
         }
-        builder.field("grant", this.grant.toString());
+        if (this.grant != null) {
+            builder.field("grant", this.grant.toString());
+        }
         if (collaborators != null) {
             builder.startArray("collaborators");
             this.collaborators.forEach(x -> {
@@ -300,7 +302,9 @@ public class Dataset implements ElasticEntity<Dataset> {
                 this.status = Short.valueOf((String) fields.get("status"));
                 this.dmp = UUID.fromString((String) fields.get("dmp"));
                 this.group = UUID.fromString((String) fields.get("group"));
-                this.grant = UUID.fromString((String) fields.get("grant"));
+                if (fields.get("grant") != null) {
+                    this.grant = UUID.fromString((String) fields.get("grant"));
+                }
                 if (fields.get("created") != null)
                     this.created = Date.from(Instant.parse((String) fields.get("created")));
                 if (fields.get("modified") != null)

dmp-backend/elastic/src/main/java/eu/eudat/elastic/entities/Dmp.java

@@ -323,7 +323,9 @@ public class Dmp implements ElasticEntity<Dmp> {
 			if (fields.get(MapKey.DATASETS.getName()) != null) {
 				this.datasets = ((List<HashMap<String, Object>>) fields.get(MapKey.DATASETS.getName())).stream().map(map -> new Dataset().fromElasticEntity(map)).collect(Collectors.toList());
 			}
-			this.grant = UUID.fromString((String) fields.get(MapKey.GRANT.getName()));
+			if (fields.containsKey(MapKey.GRANT.getName()) && fields.get(MapKey.GRANT.getName()) != null) {
+				this.grant = UUID.fromString((String) fields.get(MapKey.GRANT.getName()));
+			}
 			if (fields.get(MapKey.GRANTSTATUS.getName()) != null) {
 				this.grantStatus = Short.valueOf(fields.get(MapKey.GRANTSTATUS.getName()).toString());
 			}