[3.3.2] Fix bug while deleting devices with relations to one another (#5310)

* Fix bug while deleting devices with relations to one another

* Change log level from error to debug

* Made try catch block more precise

dao/src/main/java/org/thingsboard/server/dao/relation/BaseRelationService.java

@@ -27,6 +27,7 @@ import org.springframework.cache.CacheManager;
 import org.springframework.cache.annotation.CacheEvict;
 import org.springframework.cache.annotation.Cacheable;
 import org.springframework.cache.annotation.Caching;
+import org.springframework.dao.ConcurrencyFailureException;
 import org.springframework.stereotype.Service;
 import org.springframework.util.StringUtils;
 import org.thingsboard.server.common.data.id.EntityId;
@@ -201,6 +202,7 @@ public class BaseRelationService implements RelationService {
         }
 
         relationDao.deleteOutboundRelations(tenantId, entityId);
+
     }
 
     @Override
@@ -262,10 +264,13 @@ public class BaseRelationService implements RelationService {
     boolean delete(TenantId tenantId, Cache cache, EntityRelation relation, boolean deleteFromDb) {
         cacheEviction(relation, cache);
         if (deleteFromDb) {
-            return relationDao.deleteRelation(tenantId, relation);
-        } else {
-            return false;
+            try {
+                return relationDao.deleteRelation(tenantId, relation);
+            } catch (ConcurrencyFailureException e) {
+                log.debug("Concurrency exception while deleting relations [{}]", relation, e);
+            }
         }
+        return false;
     }
 
     private void cacheEviction(EntityRelation relation, Cache cache) {

dao/src/main/java/org/thingsboard/server/dao/sql/relation/JpaRelationDao.java

@@ -18,6 +18,7 @@ package org.thingsboard.server.dao.sql.relation;
 import com.google.common.util.concurrent.ListenableFuture;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.dao.ConcurrencyFailureException;
 import org.springframework.data.jpa.domain.Specification;
 import org.springframework.stereotype.Component;
 import org.thingsboard.server.common.data.EntityType;
@@ -163,11 +164,16 @@ public class JpaRelationDao extends JpaAbstractDaoListeningExecutorService imple
 
     @Override
     public boolean deleteOutboundRelations(TenantId tenantId, EntityId entity) {
-        boolean relationExistsBeforeDelete = relationRepository
-                .findAllByFromIdAndFromType(entity.getId(), entity.getEntityType().name())
-                .size() > 0;
-        if (relationExistsBeforeDelete) {
-            relationRepository.deleteByFromIdAndFromType(entity.getId(), entity.getEntityType().name());
+        boolean relationExistsBeforeDelete = false;
+        try {
+            relationExistsBeforeDelete = relationRepository
+                    .findAllByFromIdAndFromType(entity.getId(), entity.getEntityType().name())
+                    .size() > 0;
+            if (relationExistsBeforeDelete) {
+                relationRepository.deleteByFromIdAndFromType(entity.getId(), entity.getEntityType().name());
+            }
+        } catch (ConcurrencyFailureException e) {
+            log.debug("Concurrency exception while deleting relations [{}]", entity, e);
         }
         return relationExistsBeforeDelete;
     }