CLOUDSTACK-9607: Preventing template deletion when template is in use.

Reviewed-by: Koushik Das

Author: Priyank Parihar

api/src/org/apache/cloudstack/api/command/user/template/DeleteTemplateCmd.java

@@ -52,6 +52,9 @@ public class DeleteTemplateCmd extends BaseAsyncCmd {
     @Parameter(name = ApiConstants.ZONE_ID, type = CommandType.UUID, entityType = ZoneResponse.class, description = "the ID of zone of the template")
     private Long zoneId;
 
+    @Parameter(name = ApiConstants.FORCED, type = CommandType.BOOLEAN, required = false, description = "Force delete a template.")
+    private Boolean forced;
+
     /////////////////////////////////////////////////////
     /////////////////// Accessors ///////////////////////
     /////////////////////////////////////////////////////
@@ -64,6 +67,9 @@ public Long getZoneId() {
         return zoneId;
     }
 
+    public boolean isForced() {
+        return (forced != null) ? forced : false;
+    }
     /////////////////////////////////////////////////////
     /////////////// API Implementation///////////////////
     /////////////////////////////////////////////////////

engine/schema/src/com/cloud/vm/dao/VMInstanceDao.java

@@ -53,6 +53,14 @@ public interface VMInstanceDao extends GenericDao<VMInstanceVO, Long>, StateDao<
      */
     List<VMInstanceVO> listByPodId(long podId);
 
+    /**
+     * Lists non-expunged VMs by  templateId
+     * @param templateId
+     * @return list of VMInstanceVO deployed from the specified template, that are not expunged
+     */
+    public List<VMInstanceVO> listNonExpungedByTemplate(long templateId);
+
+
     /**
      * Lists non-expunged VMs by zone ID and templateId
      * @param zoneId

engine/schema/src/com/cloud/vm/dao/VMInstanceDaoImpl.java

@@ -72,6 +72,7 @@ public class VMInstanceDaoImpl extends GenericDaoBase<VMInstanceVO, Long> implem
     protected SearchBuilder<VMInstanceVO> IdStatesSearch;
     protected SearchBuilder<VMInstanceVO> AllFieldsSearch;
     protected SearchBuilder<VMInstanceVO> ZoneTemplateNonExpungedSearch;
+    protected SearchBuilder<VMInstanceVO> TemplateNonExpungedSearch;
     protected SearchBuilder<VMInstanceVO> NameLikeSearch;
     protected SearchBuilder<VMInstanceVO> StateChangeSearch;
     protected SearchBuilder<VMInstanceVO> TransitionSearch;
@@ -164,6 +165,12 @@ protected void init() {
         ZoneTemplateNonExpungedSearch.and("state", ZoneTemplateNonExpungedSearch.entity().getState(), Op.NEQ);
         ZoneTemplateNonExpungedSearch.done();
 
+
+        TemplateNonExpungedSearch = createSearchBuilder();
+        TemplateNonExpungedSearch.and("template", TemplateNonExpungedSearch.entity().getTemplateId(), Op.EQ);
+        TemplateNonExpungedSearch.and("state", TemplateNonExpungedSearch.entity().getState(), Op.NEQ);
+        TemplateNonExpungedSearch.done();
+
         NameLikeSearch = createSearchBuilder();
         NameLikeSearch.and("name", NameLikeSearch.entity().getHostName(), Op.LIKE);
         NameLikeSearch.done();
@@ -327,6 +334,15 @@ public List<VMInstanceVO> listByZoneIdAndType(long zoneId, VirtualMachine.Type t
         return listBy(sc);
     }
 
+    @Override
+    public List<VMInstanceVO> listNonExpungedByTemplate(long templateId) {
+        SearchCriteria<VMInstanceVO> sc = TemplateNonExpungedSearch.create();
+
+        sc.setParameters("template", templateId);
+        sc.setParameters("state", State.Expunging);
+        return listBy(sc);
+    }
+
     @Override
     public List<VMInstanceVO> listNonExpungedByZoneAndTemplate(long zoneId, long templateId) {
         SearchCriteria<VMInstanceVO> sc = ZoneTemplateNonExpungedSearch.create();

server/src/com/cloud/template/TemplateManagerImpl.java

@@ -1176,6 +1176,23 @@ public boolean deleteTemplate(DeleteTemplateCmd cmd) {
             throw new InvalidParameterValueException("unable to find template with id " + templateId);
         }
 
+        List<VMInstanceVO> vmInstanceVOList;
+        if(cmd.getZoneId() != null) {
+            vmInstanceVOList = _vmInstanceDao.listNonExpungedByZoneAndTemplate(cmd.getZoneId(), templateId);
+        }
+        else {
+            vmInstanceVOList = _vmInstanceDao.listNonExpungedByTemplate(templateId);
+        }
+        if(!cmd.isForced() && CollectionUtils.isNotEmpty(vmInstanceVOList)) {
+            StringBuilder s  = new StringBuilder("Unable to delete template with id: " + templateId + " because some VM instances are using it. ");
+            for (VMInstanceVO elm : vmInstanceVOList) {
+                s.append(elm.getInstanceName() + ", ");
+            }
+
+            s_logger.warn(s.substring(0,s.length()-2));
+            throw new InvalidParameterValueException(s.substring(0,s.length()-2));
+        }
+
         _accountMgr.checkAccess(caller, AccessType.OperateEntry, true, template);
 
         if (template.getFormat() == ImageFormat.ISO) {