huge cleanup for removing mutables used as default

[sfa.git] / sfa / util / xrn.py

diff --git a/sfa/util/xrn.py b/sfa/util/xrn.py
index e548fa5..b16ea51 100644 (file)
--- a/sfa/util/xrn.py
+++ b/sfa/util/xrn.py
@@ -109,6 +109,19 @@ class Xrn:
     def urn_split (urn):
         return Xrn.urn_meaningful(urn).split('+')
 
+    @staticmethod
+    def filter_type(urns=None, type=None):
+        if urns is None: urns=[]
+        urn_list = []
+        if not type:
+            return urns
+
+        for urn in urns:
+            xrn = Xrn(xrn=urn)
+            if (xrn.type == type):
+                # Xrn is probably a urn so we can just compare types  
+                urn_list.append(urn)
+        return urn_list
     ####################
     # the local fields that are kept consistent
     # self.urn
@@ -116,7 +129,7 @@ class Xrn:
     # self.type
     # self.path
     # provide either urn, or (hrn + type)
-    def __init__ (self, xrn, type=None, id=None):
+    def __init__ (self, xrn="", type=None, id=None):
         if not xrn: xrn = ""
         # user has specified xrn : guess if urn or hrn
         self.id = id
@@ -181,6 +194,15 @@ class Xrn:
         self.hrn = hrn 
         self.hrn_to_urn()
         self._normalize()
+
+    # sliver_id_parts is list that contains the sliver's 
+    # slice id and node id 
+    def get_sliver_id_parts(self):
+        sliver_id_parts = []
+        if self.type == 'sliver' or '-' in self.leaf:
+            sliver_id_parts = self.leaf.split('-')
+        return sliver_id_parts
+        
         
     def urn_to_hrn(self):
         """