Update SLAP interface to add exceptions

slapos/slap/interface/slap.py

@@ -35,12 +35,24 @@ class IException(Interface):
   Classes which implement IException are used to report errors.
   """
 
+class IServerError(IException):
+  """
+  Classes which implement IServerError are used to report unexpected error
+  from the slap server.
+  """
+
 class INotFoundError(IException):
   """
   Classes which implement INotFoundError are used to report missing
   informations on the slap server.
   """
 
+class IResourceNotReady(IException):
+  """
+  Classes which implement IResourceNotReady are used to report resource not
+  ready on the slap server.
+  """
+
 class IUnauthorized(IException):
   """
   Classes which implement IUnauthorized are used to report missing

slapos/slap/slap.py

@@ -140,10 +140,10 @@ class SoftwareInstance(SlapDocument):
 """Exposed exceptions"""
 # XXX Why do we need to expose exceptions?
 class ResourceNotReady(Exception):
-  pass
+  zope.interface.implements(interface.IResourceNotReady)
 
 class ServerError(Exception):
-  pass
+  zope.interface.implements(interface.IServerError)
 
 class NotFoundError(Exception):
   zope.interface.implements(interface.INotFoundError)