Allow attach custom storage backend

radicale/config.py

@@ -81,6 +81,7 @@ INITIAL_CONFIG = {
         "file": "~/.config/radicale/rights"},
     "storage": {
         "type": "filesystem",
+        "custom_handler": "",
         "filesystem_folder": os.path.expanduser(
             "~/.config/radicale/collections"),
         "database_url": ""},

radicale/storage/__init__.py

@@ -23,15 +23,20 @@ This module loads the storage backend, according to the storage
 configuration.
 
 """
-
+import sys
 from .. import config, ical
 
 
 def load():
     """Load list of available storage managers."""
     storage_type = config.get("storage", "type")
-    root_module = __import__(
-        "storage.%s" % storage_type, globals=globals(), level=2)
-    module = getattr(root_module, storage_type)
+    if storage_type == "custom":
+        storage_module = config.get("storage", "custom_handler")
+        __import__(storage_module)
+        module = sys.modules[storage_module]
+    else:
+        root_module = __import__(
+            "storage.%s" % storage_type, globals=globals(), level=2)
+        module = getattr(root_module, storage_type)
     ical.Collection = module.Collection
     return module