Update service to check device type validation at service level and return a Not Found request, if device type doesn't exist

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/api/admin/DeviceTypeManagementAdminService.java

@@ -594,7 +594,7 @@ public interface DeviceTypeManagementAdminService {
 
 
     @DELETE
-    @Path("{deviceType}/delete")
+    @Path("{deviceTypeName}/delete")
     @ApiOperation(
             httpMethod = "DELETE",
             value = "Delete device type.",
@@ -628,8 +628,8 @@ public interface DeviceTypeManagementAdminService {
     })
     Response deleteDeviceType(
             @ApiParam(
-                    name = "deviceType",
+                    name = "deviceTypeName",
                     value = "Device type name.",
                     required = true)
-            @PathParam("deviceType") String deviceType);
+            @PathParam("deviceTypeName") String deviceTypeName);
 }

components/device-mgt/org.wso2.carbon.device.mgt.api/src/main/java/org/wso2/carbon/device/mgt/jaxrs/service/impl/admin/DeviceTypeManagementAdminServiceImpl.java

@@ -320,20 +320,27 @@ public class DeviceTypeManagementAdminServiceImpl implements DeviceTypeManagemen
 
     @Override
     @DELETE
-    @Path("{deviceType}/delete")
+    @Path("{deviceTypeName}/delete")
-    public Response deleteDeviceType(@PathParam("deviceType") String deviceType) {
+    public Response deleteDeviceType(@PathParam("deviceTypeName") String deviceTypeName) {
         try {
             DeviceManagementProviderService deviceManagementProviderService =
                     DeviceMgtAPIUtils.getDeviceManagementService();
-            if (!deviceManagementProviderService.deleteDeviceType(deviceType)){
+            DeviceType deviceType = deviceManagementProviderService.getDeviceType(deviceTypeName);
-                String msg = "Error occurred while deleting device of type: " + deviceType;
+            if (deviceType == null) {
+                String msg = "Error, device of type: " + deviceTypeName + " does not exist";
+                log.error(msg);
+                return Response.status(Response.Status.NOT_FOUND).entity(msg).build();
+            }
+            if (!deviceManagementProviderService.deleteDeviceType(deviceTypeName, deviceType)){
+                String msg = "Error occurred while deleting device of type: " + deviceTypeName;
                 log.error(msg);
                 return Response.serverError().entity(msg).build();
             }
-            return Response.status(Response.Status.ACCEPTED).entity(
+            return Response.status(Response.Status.ACCEPTED)
-                    "Device of type: " + deviceType + " permanently deleted.").build();
+                    .entity("Device of type: " + deviceTypeName + " permanently deleted.")
+                    .build();
         } catch (DeviceManagementException e) {
-            String msg = "Error occurred while deleting device of type: " + deviceType;
+            String msg = "Error occurred while deleting device of type: " + deviceTypeName;
             log.error(msg, e);
             return Response.serverError().entity(msg).build();
         }

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/service/DeviceManagementProviderService.java

@@ -775,11 +775,12 @@ public interface DeviceManagementProviderService {
     /**
      * Permanently delete a device type with all it's devices
      *
-     * @param deviceTypeName device type name
+     * @param deviceTypeName Device type name
+     * @param deviceType Device type object
      * @return True if device type successfully removed
      * @throws DeviceManagementException Will be thrown if any service level or DAO level error occurs
      */
-    boolean deleteDeviceType(String deviceTypeName) throws DeviceManagementException;
+    boolean deleteDeviceType(String deviceTypeName, DeviceType deviceType) throws DeviceManagementException;
 
     /**
      * Retrieves a list of configurations of a specific device

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/service/DeviceManagementProviderServiceImpl.java

@@ -3589,25 +3589,20 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
     }
 
     @Override
-    public boolean deleteDeviceType(String deviceTypeName) throws DeviceManagementException {
+    public boolean deleteDeviceType(String deviceTypeName, DeviceType deviceType)
-        int tenantId = getTenantId();
+            throws DeviceManagementException {
         List<String> deviceIdentifiers;
         List<DeviceTypeVersion> deviceTypeVersions;
         boolean result;
+        int tenantId = getTenantId();
 
         try {
-            if (deviceTypeName.isEmpty()) {
+            if (deviceTypeName.isEmpty() || deviceType == null) {
                 String msg = "Error, device type cannot be null or empty";
                 log.error(msg);
                 return false;
             }
             DeviceManagementDAOFactory.beginTransaction();
-            DeviceType deviceTypeObj = deviceTypeDAO.getDeviceType(deviceTypeName, tenantId);
-            if (deviceTypeObj == null) {
-                String msg = "Error, device of type: " + deviceTypeName + " does not exist";
-                log.error(msg);
-                return false;
-            }
             List<Device> devices = deviceDAO.getDevices(deviceTypeName, this.getTenantId());
             if (devices.isEmpty()) {
                 if (log.isDebugEnabled()) {
@@ -3637,14 +3632,14 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
                 DeviceManagementDAOFactory.beginTransaction();
             }
             // remove device type versions
-            deviceTypeVersions = deviceTypeDAO.getDeviceTypeVersions(deviceTypeObj.getId(), deviceTypeName);
+            deviceTypeVersions = deviceTypeDAO.getDeviceTypeVersions(deviceType.getId(), deviceTypeName);
             if (deviceTypeVersions.isEmpty()) {
                 if (log.isDebugEnabled()) {
                     log.debug("Device of type: " + deviceTypeName + "doesn't have any type versions");
                 }
             } else {
                 for (DeviceTypeVersion deviceTypeVersion : deviceTypeVersions) {
-                    result = deviceTypeDAO.isDeviceTypeVersionModifiable(deviceTypeObj.getId()
+                    result = deviceTypeDAO.isDeviceTypeVersionModifiable(deviceType.getId()
                             , deviceTypeVersion.getVersionName(), tenantId);
                     if (!result) {
                         String msg = "Device type of: " + deviceTypeName + "is unauthorized to modify " +
@@ -3662,7 +3657,7 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
                 }
             }
             // delete device type
-            deviceTypeDAO.deleteDeviceType(tenantId, deviceTypeObj.getId());
+            deviceTypeDAO.deleteDeviceType(tenantId, deviceType.getId());
             DeviceManagementDAOFactory.commitTransaction();
         } catch (InvalidDeviceException e) {
             String msg = "Error occurred while deleting devices of type: " + deviceTypeName;