Added the 'Un' Index module

lib/python/SearchIndex/UnIndex.py

+##############################################################################
+# 
+# Zope Public License (ZPL) Version 1.0
+# -------------------------------------
+# 
+# Copyright (c) Digital Creations.  All rights reserved.
+# 
+# This license has been certified as Open Source(tm).
+# 
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+# 
+# 1. Redistributions in source code must retain the above copyright
+#    notice, this list of conditions, and the following disclaimer.
+# 
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions, and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 
+# 3. Digital Creations requests that attribution be given to Zope
+#    in any manner possible. Zope includes a "Powered by Zope"
+#    button that is installed by default. While it is not a license
+#    violation to remove this button, it is requested that the
+#    attribution remain. A significant investment has been put
+#    into Zope, and this effort will continue if the Zope community
+#    continues to grow. This is one way to assure that growth.
+# 
+# 4. All advertising materials and documentation mentioning
+#    features derived from or use of this software must display
+#    the following acknowledgement:
+# 
+#      "This product includes software developed by Digital Creations
+#      for use in the Z Object Publishing Environment
+#      (http://www.zope.org/)."
+# 
+#    In the event that the product being advertised includes an
+#    intact Zope distribution (with copyright and license included)
+#    then this clause is waived.
+# 
+# 5. Names associated with Zope or Digital Creations must not be used to
+#    endorse or promote products derived from this software without
+#    prior written permission from Digital Creations.
+# 
+# 6. Modified redistributions of any form whatsoever must retain
+#    the following acknowledgment:
+# 
+#      "This product includes software developed by Digital Creations
+#      for use in the Z Object Publishing Environment
+#      (http://www.zope.org/)."
+# 
+#    Intact (re-)distributions of any official Zope release do not
+#    require an external acknowledgement.
+# 
+# 7. Modifications are encouraged but must be packaged separately as
+#    patches to official Zope releases.  Distributions that do not
+#    clearly separate the patches from the original work must be clearly
+#    labeled as unofficial distributions.  Modifications which do not
+#    carry the name Zope may be packaged in any form, as long as they
+#    conform to all of the clauses above.
+# 
+# 
+# Disclaimer
+# 
+#   THIS SOFTWARE IS PROVIDED BY DIGITAL CREATIONS ``AS IS'' AND ANY
+#   EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+#   PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL DIGITAL CREATIONS OR ITS
+#   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+#   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+#   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+#   USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+#   ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+#   OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+#   OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+#   SUCH DAMAGE.
+# 
+# 
+# This software consists of contributions made by Digital Creations and
+# many individuals on behalf of Digital Creations.  Specific
+# attributions are listed in the accompanying credits file.
+# 
+##############################################################################
+
+"""Simple column indices"""
+__version__='$Revision: 1.1 $'[11:-2]
+
+from Globals import Persistent
+import BTree
+import IOBTree
+from intSet import intSet
+import operator
+from Missing import MV
+import string
+
+ListType=type([])
+StringType=type('s')
+
+
+def nonEmpty(s):
+    "returns true if a non-empty string or any other (nonstring) type"
+    if type(s) is StringType:
+        if s: return 1
+        else: return 0
+    else:
+        return 1
+
+
+class UnIndex(Persistent):
+    """UnIndex object interface"""
+
+    def __init__(self, id=None, ignore_ex=None, call_methods=None):
+        """Create an unindex
+
+        UnIndexes are indexes that contain two index components, the
+        forward index (like plain index objects) and an inverted
+        index.  The inverted index is so that objects can be unindexed 
+        even when the old value of the object is not known.
+
+        The arguments are:
+
+          'id' -- the name of the item attribute to index.  This is
+          either an attribute name or a record key.
+
+          'ignore_ex' -- should be set to true if you want the index
+          to ignore exceptions raised while indexing instead of
+          propagating them.
+
+          'call_methods' -- should be set to true if you want the index 
+          to call the attribute 'id' (note: 'id' should be callable!)
+          You will also need to pass in an object in the index and
+          uninded methods for this to work.
+
+        """
+	######################################################################
+	# For b/w compatability, have to allow __init__ calls with zero args
+
+        if not id==ignore_ex==call_methods==None:
+            self.id = id
+            self.ignore_ex=ignore_ex        # currently unimplimented
+            self.call_methods=call_methods
+            self._index = BTree.BTree()
+            self._unindex = IOBTree.BTree()
+
+        else:
+            pass
+
+
+    def index_object(self, i, obj):
+        """ index and object 'obj' with integer id 'i'"""
+        index = self._index
+        unindex = self._unindex
+
+        id = self.id
+        k=getattr(obj, id)
+
+        if self.call_methods:
+            k=k()
+        if k is None or k == MV:
+            return
+
+        set = index.get(k)
+        if set is None: 
+            index[k] = set = intSet()
+
+        set.insert(i)
+        unindex[i] = k
+
+
+    def unindex_object(self, i):
+        """ Unindex the object with integer id 'i' """
+        index = self._index
+        unindex = self._unindex
+
+        k = unindex[i]
+        if k is None:
+            return None
+        set = index.get(k)
+        if set is not None: set.remove(i)
+
+
+    def _apply_index(self, request, cid=''): 
+        """Apply the index to query parameters given in the argument,
+        request
+
+        The argument should be a mapping object.
+
+        If the request does not contain the needed parameters, then
+        None is returned.
+
+        If the request contains a parameter with the name of the
+        column + '_usage', it is sniffed for information on how to
+        handle applying the index.
+
+        Otherwise two objects are returned.  The first object is a
+        ResultSet containing the record numbers of the matching
+        records.  The second object is a tuple containing the names of
+        all data fields used.
+
+        """
+        id = self.id              #name of the column
+
+        cidid = "%s/%s" % (cid,id)
+        has_key = request.has_key
+        if has_key(cidid): keys = request[cidid]
+        elif has_key(id): keys = request[id]
+        else: return None
+
+        if type(keys) is not ListType: keys=[keys]
+        index = self._index
+        r = None
+        anyTrue = 0
+        opr = None
+
+        if request.has_key(id+'_usage'):
+            # see if any usage params are sent to field
+            opr=string.split(string.lower(request[id+"_usage"]),':')
+            opr, opr_args=opr[0], opr[1:]
+
+        if opr=="range":
+            if 'min' in opr_args: lo = min(keys)
+            else: lo = None
+            if 'max' in opr_args: hi = max(keys)
+            else: hi = None
+
+            anyTrue=1
+            try:
+                if hi: setlist = index.items(lo,hi)
+                else:  setlist = index.items(lo)
+                for k,set in setlist:
+                    if r is None: r = set
+                    else: r = r.union(set)
+            except KeyError: pass
+        else:           #not a range
+            get = index.get
+            for key in keys:
+                if key: anyTrue = 1
+                set=get(key)
+                if set is not None:
+                    if r is None: r = set
+                    else: r = r.union(set)
+
+        if r is None:
+            if anyTrue: r=intSet()
+            else: return None
+
+        return r, (id,)
+
+
+    def hasUniqueValuesFor(self, name):
+        ' has unique values for column NAME '
+        if name == self.id:
+            return 1
+        else:
+            return 0
+
+
+    def uniqueValues(self, name=None, withLengths=0):
+        """\
+        returns the unique values for name
+
+        if withLengths is true, returns a sequence of
+        tuples of (value, length)
+        """
+        if name is None:
+            name = self.id
+        elif name != self.id:
+            return []
+        if not withLengths: return tuple(
+            filter(nonEmpty,self._index.keys())
+            )
+        else: 
+            rl=[]
+            for i in self._index.keys():
+                if not nonEmpty(i): continue
+                else: rl.append((i, len(self._index[i])))
+            return tuple(rl)
+
+
+    def clear(self):
+        self._index = BTree.BTree()
+        self._unindex = IOBTree.BTree()
+
+
+