Validate config_db.json in reload path.

config/main.py

@@ -2161,7 +2161,10 @@ def reload(db, filename, yes, load_sysinfo, no_service_restart, force, file_form
             click.echo("Input {} config file(s) separated by comma for multiple files ".format(num_cfg_file))
             return
 
-    if filename is not None and filename != "/dev/stdin":
+    if filename is None and file_format == 'config_db':
+        # Validate the default config before stopping services and flushing CONFIG_DB.
+        config_file_yang_validation(DEFAULT_CONFIG_DB_FILE)
+    elif filename is not None and filename != "/dev/stdin":
         if multi_asic.is_multi_asic():
             for cfg_file in cfg_files:
                 if cfg_file is not None:

tests/config_test.py

@@ -728,8 +728,12 @@ def setup_class(cls):
         open(cls.dummy_cfg_file, 'w').close()
 
     def test_config_reload(self, get_cmd_module, setup_single_broadcom_asic):
-        with mock.patch("utilities_common.cli.run_command", mock.MagicMock(side_effect=mock_run_command_side_effect)) as mock_run_command:
-            (config, show) = get_cmd_module
+        (config, show) = get_cmd_module
+
+        with mock.patch(
+                "utilities_common.cli.run_command",
+                mock.MagicMock(side_effect=mock_run_command_side_effect)), \
+                mock.patch.object(config, "config_file_yang_validation") as mock_validate_config:
 
             jsonfile_config = os.path.join(mock_db_path, "config_db.json")
             jsonfile_init_cfg = os.path.join(mock_db_path, "init_cfg.json")
@@ -753,6 +757,23 @@ def test_config_reload(self, get_cmd_module, setup_single_broadcom_asic):
 
             assert "\n".join([line.rstrip() for line in result.output.split('\n')][:2]) == \
                 reload_config_with_sys_info_command_output.format(config.SYSTEM_RELOAD_LOCK)
+            mock_validate_config.assert_called_once_with(jsonfile_config)
+
+    def test_config_reload_default_config_validation_failure(self, get_cmd_module, setup_single_broadcom_asic):
+        (config, show) = get_cmd_module
+
+        jsonfile_config = os.path.join(mock_db_path, "config_db.json")
+        config.DEFAULT_CONFIG_DB_FILE = jsonfile_config
+
+        with mock.patch("utilities_common.cli.run_command") as mock_run_command, \
+                mock.patch.object(
+                    config, "config_file_yang_validation", side_effect=click.Abort) as mock_validate_config:
+            runner = CliRunner()
+            result = runner.invoke(config.config.commands["reload"], ["-y", "-f"])
+
+            assert result.exit_code != 0
+            mock_validate_config.assert_called_once_with(jsonfile_config)
+            mock_run_command.assert_not_called()
 
     def test_config_reload_stdin(self, get_cmd_module, setup_single_broadcom_asic):
         def mock_json_load(f):