Usage: do not add a second backup usage row on offering re-assign

Removing a backup offering while keeping the backups leaves its usage row
active. Re-assigning the same offering added another active row, so the
same backups were billed twice. Skip the new row when one is active.

Author: abh1sar

usage/src/main/java/com/cloud/usage/UsageManagerImpl.java

@@ -2038,7 +2038,7 @@ private void createVmSnapshotOnPrimaryEvent(UsageEventVO event) {
         }
     }
 
-    private void createBackupEvent(final UsageEventVO event) {
+    protected void createBackupEvent(final UsageEventVO event) {
         Long vmId = event.getResourceId();
         Long zoneId = event.getZoneId();
         Long accountId = event.getAccountId();
@@ -2048,6 +2048,12 @@ private void createBackupEvent(final UsageEventVO event) {
         Date created = event.getCreateDate();
 
         if (EventTypes.EVENT_VM_BACKUP_OFFERING_ASSIGN.equals(event.getType())) {
+            // Removing the offering while keeping the backups leaves the usage active, so re-assigning the
+            // same offering must not add a second row that bills the same backups again.
+            if (!usageBackupDao.listActiveUsage(vmId, backupOfferingId).isEmpty()) {
+                logger.debug("VM [{}] already has active usage for backup offering [{}], not creating another usage entry.", vmId, backupOfferingId);
+                return;
+            }
             final UsageBackupVO backupVO = new UsageBackupVO(zoneId, accountId, domainId, vmId, backupOfferingId, created);
             usageBackupDao.persist(backupVO);
         } else if (EventTypes.EVENT_VM_BACKUP_OFFERING_REMOVED_AND_BACKUPS_DELETED.equals(event.getType())) {

usage/src/test/java/com/cloud/usage/UsageManagerImplTest.java

@@ -17,9 +17,11 @@
 package com.cloud.usage;
 
 import java.util.ArrayList;
+import java.util.Date;
 import java.util.List;
 
 import com.cloud.event.dao.UsageEventDetailsDao;
+import com.cloud.usage.dao.UsageBackupDao;
 import com.cloud.usage.dao.UsageVMSnapshotDao;
 import org.junit.Before;
 import org.junit.Test;
@@ -58,6 +60,9 @@ public class UsageManagerImplTest {
     @Mock
     private AccountDao accountDaoMock;
 
+    @Mock
+    private UsageBackupDao usageBackupDaoMock;
+
     @Mock
     private UsageVPNUserVO vpnUserMock;
 
@@ -243,4 +248,46 @@ public void handleVMSnapshotEventTestEventIsNeitherAddNorRemove() {
         Mockito.verify(usageManagerImpl, Mockito.never()).createUsageVpnUser(usageEventVOMock,accountMock);
         Mockito.verify(usageManagerImpl, Mockito.never()).deleteUsageVpnUser(usageEventVOMock, accountMock);
     }
+
+    private void mockBackupEvent(String type) {
+        Mockito.when(usageEventVOMock.getType()).thenReturn(type);
+        Mockito.when(usageEventVOMock.getResourceId()).thenReturn(10L);
+        Mockito.when(usageEventVOMock.getZoneId()).thenReturn(1L);
+        Mockito.when(usageEventVOMock.getAccountId()).thenReturn(accountMockId);
+        Mockito.when(usageEventVOMock.getOfferingId()).thenReturn(20L);
+    }
+
+    @Test
+    public void createBackupEventTestAssignCreatesUsage() {
+        mockBackupEvent(EventTypes.EVENT_VM_BACKUP_OFFERING_ASSIGN);
+        Mockito.when(usageEventVOMock.getCreateDate()).thenReturn(new Date());
+        Mockito.when(usageBackupDaoMock.listActiveUsage(10L, 20L)).thenReturn(new ArrayList<>());
+
+        usageManagerImpl.createBackupEvent(usageEventVOMock);
+
+        Mockito.verify(usageBackupDaoMock).persist(Mockito.any(UsageBackupVO.class));
+    }
+
+    @Test
+    public void createBackupEventTestAssignSkipsWhenUsageIsActive() {
+        mockBackupEvent(EventTypes.EVENT_VM_BACKUP_OFFERING_ASSIGN);
+        Mockito.when(usageBackupDaoMock.listActiveUsage(10L, 20L)).thenReturn(List.of(Mockito.mock(UsageBackupVO.class)));
+
+        usageManagerImpl.createBackupEvent(usageEventVOMock);
+
+        Mockito.verify(usageBackupDaoMock, Mockito.never()).persist(Mockito.any(UsageBackupVO.class));
+    }
+
+    @Test
+    public void createBackupEventTestMetricPassesEventDate() {
+        Date eventDate = new Date();
+        mockBackupEvent(EventTypes.EVENT_VM_BACKUP_USAGE_METRIC);
+        Mockito.when(usageEventVOMock.getCreateDate()).thenReturn(eventDate);
+        Mockito.when(usageEventVOMock.getSize()).thenReturn(100L);
+        Mockito.when(usageEventVOMock.getVirtualSize()).thenReturn(1000L);
+
+        usageManagerImpl.createBackupEvent(usageEventVOMock);
+
+        Mockito.verify(usageBackupDaoMock).updateMetrics(10L, 20L, 100L, 1000L, eventDate);
+    }
 }