dos2unix'ed

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

diff --git a/sfa/util/xrn.py b/sfa/util/xrn.py
index 752e7a9..4709b49 100644 (file)
--- a/sfa/util/xrn.py
+++ b/sfa/util/xrn.py
@@ -1,3 +1,26 @@
+#----------------------------------------------------------------------
+# Copyright (c) 2008 Board of Trustees, Princeton University
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and/or hardware specification (the "Work") to
+# deal in the Work without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Work, and to permit persons to whom the Work
+# is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Work.
+#
+# THE WORK IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 
+# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 
+# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
+# OUT OF OR IN CONNECTION WITH THE WORK OR THE USE OR OTHER DEALINGS 
+# IN THE WORK.
+#----------------------------------------------------------------------
+
 import re
 
 from sfa.util.faults import *
@@ -7,6 +30,10 @@ def get_leaf(hrn): return Xrn(hrn).get_leaf()
 def get_authority(hrn): return Xrn(hrn).get_authority_hrn()
 def urn_to_hrn(urn): xrn=Xrn(urn); return (xrn.hrn, xrn.type)
 def hrn_to_urn(hrn,type): return Xrn(hrn, type=type).urn
+def hrn_authfor_hrn(parenthrn, hrn): return Xrn.hrn_is_auth_for_hrn(parenthrn, hrn)
+
+def urn_to_sliver_id(urn, slice_id, node_id, index=0):
+    return ":".join([urn, slice_id, node_id, index])
 
 class Xrn:
 
@@ -33,10 +60,38 @@ class Xrn:
     # e.g. escape ('a.b') -> 'a\.b'
     @staticmethod
     def escape(token): return re.sub(r'([^\\])\.', r'\1\.', token)
+
     # e.g. unescape ('a\.b') -> 'a.b'
     @staticmethod
     def unescape(token): return token.replace('\\.','.')
-        
+
+    # Return the HRN authority chain from top to bottom.
+    # e.g. hrn_auth_chain('a\.b.c.d') -> ['a\.b', 'a\.b.c']
+    @staticmethod
+    def hrn_auth_chain(hrn):
+        parts = Xrn.hrn_auth_list(hrn)
+        chain = []
+        for i in range(len(parts)):
+            chain.append('.'.join(parts[:i+1]))
+        # Include the HRN itself?
+        #chain.append(hrn)
+        return chain
+
+    # Is the given HRN a true authority over the namespace of the other
+    # child HRN?
+    # A better alternative than childHRN.startswith(parentHRN)
+    # e.g. hrn_is_auth_for_hrn('a\.b', 'a\.b.c.d') -> True,
+    # but hrn_is_auth_for_hrn('a', 'a\.b.c.d') -> False
+    # Also hrn_is_uauth_for_hrn('a\.b.c.d', 'a\.b.c.d') -> True
+    @staticmethod
+    def hrn_is_auth_for_hrn(parenthrn, hrn):
+        if parenthrn == hrn:
+            return True
+        for auth in Xrn.hrn_auth_chain(hrn):
+            if parenthrn == auth:
+                return True
+        return False
+
     URN_PREFIX = "urn:publicid:IDN"
 
     ########## basic tools on URNs