server: fix diskoffering details in vm response (apache#8135)

Fixes apache#8120

Author: shwstppr

api/src/main/java/org/apache/cloudstack/api/response/UserVmResponse.java

@@ -166,11 +166,11 @@ public class UserVmResponse extends BaseResponseWithTagInformation implements Co
     private String serviceOfferingName;
 
     @SerializedName(ApiConstants.DISK_OFFERING_ID)
-    @Param(description = "the ID of the disk offering of the virtual machine", since = "4.4")
+    @Param(description = "the ID of the disk offering of the virtual machine. This parameter should not be used for retrieving disk offering details of DATA volumes. Use listVolumes API instead", since = "4.4")
     private String diskOfferingId;
 
     @SerializedName("diskofferingname")
-    @Param(description = "the name of the disk offering of the virtual machine", since = "4.4")
+    @Param(description = "the name of the disk offering of the virtual machine. This parameter should not be used for retrieving disk offering details of DATA volumes. Use listVolumes API instead", since = "4.4")
     private String diskOfferingName;
 
     @SerializedName(ApiConstants.BACKUP_OFFERING_ID)

server/src/main/java/com/cloud/api/query/dao/UserVmJoinDaoImpl.java

@@ -29,6 +29,7 @@
 import javax.inject.Inject;
 
 import com.cloud.vm.VirtualMachine;
+import com.cloud.storage.Volume;
 import org.apache.cloudstack.affinity.AffinityGroupResponse;
 import org.apache.cloudstack.annotation.AnnotationService;
 import org.apache.cloudstack.annotation.dao.AnnotationDao;
@@ -45,6 +46,7 @@
 import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
 import org.apache.cloudstack.query.QueryService;
 import org.apache.commons.lang3.BooleanUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.apache.log4j.Logger;
 import org.springframework.stereotype.Component;
 
@@ -602,6 +604,11 @@ public UserVmResponse setUserVmResponse(ResponseView view, UserVmResponse userVm
             userVmData.addAffinityGroup(resp);
         }
 
+        if (StringUtils.isEmpty(userVmData.getDiskOfferingId()) && !Volume.Type.ROOT.equals(uvo.getVolumeType())) {
+            userVmData.setDiskOfferingId(uvo.getDiskOfferingUuid());
+            userVmData.setDiskOfferingName(uvo.getDiskOfferingName());
+        }
+
         return userVmData;
     }