diff --git a/radicale_odoo_storage/__init__.py b/radicale_odoo_storage/__init__.py
index a414349..9b9fd25 100644
--- a/radicale_odoo_storage/__init__.py
+++ b/radicale_odoo_storage/__init__.py
@@ -22,20 +22,39 @@ import threading
 from contextlib import contextmanager
 from odoorpc import ODOO
 from odoorpc.error import RPCError
-from radicale.storage import Collection as RadicaleCollection
+from radicale.storage import BaseCollection
 
 
-class Collection(RadicaleCollection):
+class Collection(BaseCollection):
     """ BaseCollection implementation for Odoo Radicale Storage """
 
     odoo = False
 
-    def __init__(self, path, principal=None, folder=None, filesystem_path=None):
+    def __init__(self, path):
         """ Init function """
-        super(Collection, self).__init__(path, principal, folder, filesystem_path)
         if not self.odoo:
-            self.odoo_connect()
-            self.odoo_init()
+            self.__class__.odoo_connect()
+            # self.odoo_init()
+
+        attributes = path.strip('/').split('/')
+        self.tag = None
+        self.props = {}
+        if 'odoo-contact' in attributes:
+            self.tag = 'VADDRESSBOOK'
+            self.content_suffix = '.vcf'
+            self.props.update({'tag': 'VADDRESSBOOK',
+                               'D:displayname': 'Odoo contacts',
+                               'CR:addressbook-description': 'Contacts form your Odoo account'})
+        elif 'odoo-calendar' in attributes:
+            self.tag = 'VCALENDAR'
+            self.content_suffix = '.ics'
+            self.props.update({'tag': 'VCALENDAR',
+                               'D:displayname': 'Odoo calendar',
+                               'C:calendar-description': 'Events form your Odoo calendar'})
+
+        self.path = path.strip('/')
+        self.owner = attributes[0]
+        self.is_principal = len(attributes) == 0
 
     @classmethod
     def odoo_connect(cls):
@@ -83,3 +102,48 @@ class Collection(RadicaleCollection):
                          'C:calendar-description': 'Events form your Odoo calendar'}
                 self.create_collection(calendar_path, props=props)
                 self.logger.info('Collection creation for Odoo Sync : %s' % calendar_path)
+
+
+    @classmethod
+    @contextmanager
+    def acquire_lock(cls, mode, user=None):
+        cls.user = user
+        yield
+
+    @classmethod
+    def discover(cls, path, depth="0"):
+        """Discover a list of collections under the given ``path``.
+
+        ``path`` is sanitized.
+
+        If ``depth`` is "0", only the actual object under ``path`` is
+        returned.
+
+        If ``depth`` is anything but "0", it is considered as "1" and direct
+        children are included in the result.
+
+        The root collection "/" must always exist.
+
+        """
+        attributes = path.strip('/').split('/') or []
+        if path and not cls.user:
+            cls.user = attributes[0]
+
+        cls.logger.warning('Discover : %s (path), %s (depth), %s (cls.user), %s (attributes)' %
+                           (path, depth, cls.user, attributes))
+        yield cls(path)
+        contact_path = '%s/odoo-contact' % path
+        calendar_path = '%s/odoo-calendar' % path
+        yield cls(contact_path)
+        yield cls(calendar_path)
+
+    def get_meta(self, key=None):
+        """Get metadata value for collection """
+        if key == 'tag':
+            return self.tag
+        return self.props.get(key)
+
+    @classmethod
+    def create_collection(cls, href, collection=None, props=None):
+        """ Create collection implementation : only warns ATM """
+        cls.logger.error('Attemmpt to create a new collection for %s' % href)