first draft of the Xrn class, designed to replace sfa.util.namespace

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

diff --git a/sfa/util/namespace.py b/sfa/util/namespace.py
index 512f398..961b3b3 100644 (file)
--- a/sfa/util/namespace.py
+++ b/sfa/util/namespace.py
@@ -1,32 +1,72 @@
-### $Id$
-### $URL$
+#
+#  WARNING - This file should be soon deprecated in favor of sfa.util.xrn
+#
+#
+#  WARNING - This file should be soon deprecated in favor of sfa.util.xrn
+#
+#
+#  WARNING - This file should be soon deprecated in favor of sfa.util.xrn
+#
+#
+#  WARNING - This file should be soon deprecated in favor of sfa.util.xrn
+#
+#
+#  WARNING - This file should be soon deprecated in favor of sfa.util.xrn
+#
+#
+#  WARNING - This file should be soon deprecated in favor of sfa.util.xrn
+#
 import re
 from sfa.util.faults import *
 URN_PREFIX = "urn:publicid:IDN"
 
+def __get_hierarchy_delim_indexes(hrn):
+    # find all non escaped '.'
+    hierarchy_delim = '([a-zA-Z0-9][\.])'
+    parts = re.findall(hierarchy_delim, hrn)
+    # list of indexes for every  hierarchy delimieter
+    indexes = []
+    for part in parts:
+        indexes.append(hrn.index(part) + 1)
+    return indexes 
+
 def get_leaf(hrn):
-    parts = hrn.split(".")
-    return ".".join(parts[-1:])
+    delim_indexes = __get_hierarchy_delim_indexes(hrn)
+    if not delim_indexes:
+        return hrn
+    
+    last_delim_index = delim_indexes[-1:][0] + 1
+    return hrn[last_delim_index:] 
 
 def get_authority(xrn):
     hrn, type = urn_to_hrn(xrn)
     if type and type == 'authority':
         return hrn
+  
+    delim_indexes = __get_hierarchy_delim_indexes(hrn)
+    if not delim_indexes:
+        return ''
+    last_delim_index = delim_indexes[-1:][0] 
+    return hrn[:last_delim_index] 
     
-    parts = hrn.split(".")
-    return ".".join(parts[:-1])
-
 def hrn_to_pl_slicename(hrn):
+    # remove any escaped no alpah numeric characters
+    #hrn = re.sub('\\\[^a-zA-Z0-9]', '', hrn)
+    hrn = re.sub(r'\\(.)', '', hrn)
     parts = hrn.split(".")
     return parts[-2] + "_" + parts[-1]
 
 # assuming hrn is the hrn of an authority, return the plc authority name
 def hrn_to_pl_authname(hrn):
+    # remove any escaped no alpah numeric characters
+    hrn = re.sub(r'\\(.)', '', hrn)
     parts = hrn.split(".")
     return parts[-1]
 
 # assuming hrn is the hrn of an authority, return the plc login_base
 def hrn_to_pl_login_base(hrn):
+    # remove any escaped no alpah numeric characters
+    hrn = re.sub(r'\\(.)', '', hrn)
     return hrn_to_pl_authname(hrn)
 
 def hostname_to_hrn(auth_hrn, login_base, hostname):
@@ -57,9 +97,6 @@ def urn_to_hrn(urn):
     """
     convert a urn to hrn
     return a tuple (hrn, type)
-    Warning: urn_to_hrn() replces some special characters that 
-    are not replaced in hrn_to_urn(). Due to this, 
-    urn_to_hrn() -> hrn_to_urn() may not return the original urn
     """
 
     # if this is already a hrn dont do anything
@@ -67,22 +104,21 @@ def urn_to_hrn(urn):
         return urn, None
 
     name = urn[len(URN_PREFIX):]
-    hrn_parts = name.split("+")
-    type = hrn_parts.pop(2)
+    urn_parts = name.split("+")
+    type = urn_parts.pop(2)
     
          
     # Remove the authority name (e.g. '.sa')
     if type == 'authority':
-        hrn_parts = hrn_parts[:-1]
+        urn_parts = urn_parts[:-1]
 
-    # convert hrn_parts (list) into hrn (str) by doing the following    
-    # dont allow special characters (except ':') in the site login base
-    # remove blank elements
-    # replace ':' with '.'
-    # join list elements using '.'
-    only_alphanum = re.compile('[^a-zA-Z0-9:]+')
-    valid_chars = lambda x: only_alphanum.sub('', x).replace(':', '.')
-    hrn = '.'.join([valid_chars(part) for part in hrn_parts if part]) 
+    # convert hrn_parts (list) into hrn (str) by doing the following
+    # 1. remove blank elements
+    # 2. escape all non alpha numeric chars (excluding ':')
+    # 3. replace ':' with '.'  (':' is the urn hierarchy delimiter)
+    # 4. join list elements using '.' 
+    #hrn = '.'.join([part.replace('.', '\\.').replace(':', '.') for part in hrn_parts if part]) 
+    hrn = '.'.join([re.sub(r'([^a-zA-Z0-9\:])', r'\\\1', part).replace(':', '.') for part in urn_parts if part]) 
     
     return str(hrn), str(type) 
     
@@ -95,20 +131,22 @@ def hrn_to_urn(hrn, type=None):
     if not hrn or hrn.startswith(URN_PREFIX):
         return hrn
 
-    authority = get_authority(hrn)
-    name = get_leaf(hrn)
-     
     if type == 'authority':
         authority = hrn
         name = 'sa'   
+    else:
+        authority = get_authority(hrn)
+        name = get_leaf(hrn)   
+  
+    # convert from hierarchy delimiter from '.' to ':'   
+    authority = re.sub(r'([a-zA-Z0-9])[\.]', r'\1:', authority) 
+    # unescape escaped characters
+    authority = re.sub(r'\\(.)', r'\1', authority)
     
-    if authority.startswith("plc"):
-        if type == None:
-            urn = "+".join(['',authority.replace('.',':'),name])
-        else:
-            urn = "+".join(['',authority.replace('.',':'),type,name])
-
+    if type == None:
+        urn = "+".join(['',authority,name])
     else:
         urn = "+".join(['',authority,type,name])
+
         
     return URN_PREFIX + urn