This commit was manufactured by cvs2svn to create branch

[plcapi.git] / PLC / Filter.py

diff --git a/PLC/Filter.py b/PLC/Filter.py
index a7c14ce..49990c6 100644 (file)
--- a/PLC/Filter.py
+++ b/PLC/Filter.py
@@ -1,11 +1,19 @@
+from types import StringTypes
+try:
+    set
+except NameError:
+    from sets import Set
+    set = Set
+
 from PLC.Faults import *
 from PLC.Parameter import Parameter, Mixed, python_type
 
 class Filter(Parameter, dict):
     """
     A type of parameter that represents a filter on one or more
-    columns of a database table. fields should be a dictionary of
-    field names and types, e.g.
+    columns of a database table.
+
+    field should be a dictionary of field names and types, e.g.
 
     {'node_id': Parameter(int, "Node identifier"),
      'hostname': Parameter(int, "Fully qualified hostname", max = 255),
@@ -17,6 +25,14 @@ class Filter(Parameter, dict):
     representing an intersection (if join_with is AND) or union (if
     join_with is OR) filter. If a value is a sequence type, then it
     should represent a list of possible values for that field.
+
+    Special forms:
+    * a field starting with the ~ character means negation.
+    example :  { '~peer_id' : None }
+    * a (string) value containing either a * or a % character is
+      treated as a (sql) pattern; * are replaced with % that is the
+      SQL wildcard character.
+    example :  { 'hostname' : '*.jp' } 
     """
 
     def __init__(self, fields = {}, filter = {}, doc = "Attribute filter"):
@@ -53,6 +69,12 @@ class Filter(Parameter, dict):
             assert join_with in ("AND", "OR")
 
         for field, value in self.iteritems():
+            # provide for negation with a field starting with ~
+            negation=False
+            if field[0] == '~':
+                negation = True
+                field = field[1:]
+
             if field not in self.fields:
                 raise PLCInvalidArgument, "Invalid filter field '%s'" % field
 
@@ -68,10 +90,18 @@ class Filter(Parameter, dict):
                 if value is None:
                     operator = "IS"
                     value = "NULL"
-                else:
+                elif isinstance(value, StringTypes) and \
+                     (value.find("*") > -1 or value.find("%") > -1):
+                   operator = "LIKE"
+                    value = str(api.db.quote(value.replace("*", "%")))
+               else:
                     operator = "="
                     value = str(api.db.quote(value))
 
-            conditionals.append("%s %s %s" % (field, operator, value))
+            clause = "%s %s %s" % (field, operator, value)
+            if negation:
+                clause = " ( NOT %s ) "%clause
+                
+            conditionals.append(clause)
 
         return (" %s " % join_with).join(conditionals)