距离排序默认升序

app/Http/Controllers/Api/AgentProductController.php

@@ -50,6 +50,7 @@ round(
 	)) * 1000),0) AS `distance_m`
 SQL
 			));
+			$by = $formData['by'] ?? 1; //距离排序默认升序
 		}
 		$fields = ['id', 'sale', 'updated_at', 'price', 'distance_m']; //排序字段