Refactoring, Removal of most global vars, config default path is ~/ucloud/

ucloud/common/storage_handlers.py

@@ -7,6 +7,8 @@ from abc import ABC
 from . import logger
 from os.path import join as join_path
 
+from ucloud.settings import settings as config
+
 
 class ImageStorageHandler(ABC):
     def __init__(self, image_base, vm_base):
@@ -156,3 +158,19 @@ class CEPHBasedImageStorageHandler(ImageStorageHandler):
         path = join_path(self.vm_base, path)
         command = ["rbd", "info", path]
         return self.execute_command(command, report=False)
+
+
+def get_storage_handler():
+    __storage_backend = config['storage']['storage_backend']
+    if __storage_backend == 'filesystem':
+        return FileSystemBasedImageStorageHandler(
+            vm_base=config['storage']['vm_dir'],
+            image_base=config['storage']['image_dir']
+        )
+    elif __storage_backend == 'ceph':
+        return CEPHBasedImageStorageHandler(
+            vm_base=config['storage']['ceph_vm_pool'],
+            image_base=config['storage']['ceph_image_pool']
+        )
+    else:
+        raise Exception('Unknown Image Storage Handler')