Beispiel #1
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 def testAppend(self):
     "Test appending a single item to a ResultSet"
     rs = SimpleResultSet(self.session)
     self.assertEqual(len(rs), 0)
     rs.append(self.rsi1)
     self.assertEqual(len(rs), 1)
     self.assertEqual(rs[-1], self.rsi1)
Beispiel #2
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 def testCombineSumWeights(self):
     "Test combining ResultSet scores by summation."
     # A clause / boolean is required to combine ResultSets
     # Use TF-IDF because it's most simple to calculate
     clause = cqlparse('my.index '
                       'all/rel.algorithm=tfidf/rel.combine=sum '
                       '"foo bar"')
     
     clause.addPrefix('rel', "info:srw/cql-context-set/2/relevance-1.2")
     # A Database is required for relevance ranking
     db = FakeDatabase(self.session, None, parent=None)
     # Create a new ResultSet to combine into
     rs = SimpleResultSet(self.session)
     rs = rs.combine(self.session, [self.a, self.b], clause, db)
     # Check return value is a Resultset
     self.assertIsInstance(rs, SimpleResultSet)
     # Check merged ResultSet has 1 item
     self.assertEqual(len(rs), 1)
     # Check that merged ResultSet contains the correct item
     self.assertIn(self.rsi1, rs)
     for rsi in rs:
         # Check that each ResultSetItem has a score (weight)
         self.assertTrue(hasattr(rsi, 'weight'))
         # Check that each ResultSetItem has a scaled score less than 1
         self.assertLessEqual(rsi.scaledWeight, 1.0)
     # Check combined scores correct
     matches = len(self.b)
     self.assertEqual(rs[0].weight,
                      sum([5 * math.log(db.totalItems / matches),
                           3 * math.log(db.totalItems / matches)
                           ]
                          )
                      )
Beispiel #3
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    def _search(self, session, query):
        if not hasattr(query, 'leftOperand'):
            # Check resultset
            rsid = query.getResultSetId()
            if (rsid):
                # Get existing result set
                if rsid.find('/') > -1:
                    (rssid, rsid) = rsid.split('/', 1)
                    rss = self.get_object(session, rssid)
                else:
                    rss = self.get_object(session, "defaultResultSetStore")
                rset =  rss.fetch_resultSet(session, rsid)
                rset.fromStore = 1
                return rset
            else:
                pm = self.get_path(session, 'protocolMap')
                if not pm:
                    self._cacheProtocolMaps(session)
                    pm = self.protocolMaps.get('http://www.loc.gov/zing/srw/')
                    self.paths['protocolMap'] = pm
                idx = pm.resolveIndex(session, query)
                if (idx != None):
                    query.config = pm
                    rs = idx.search(session, query, self)
                    query.config = None
                    rs.query = query
                    return rs
                else:
                    # unsupported index
                    raise ObjectDoesNotExistException(query.index.toCQL())

        else:
            # get the indexStore
            left = self._search(session, query.leftOperand)
            right = self._search(session, query.rightOperand)
            if left.__class__ == right.__class__:
                new = left.__class__(session, [], recordStore=left.recordStore)
            elif left.__class__ == BitmapResultSet:
                # Want to switch the left/right, but rset assumes list[0] is same type
                new = right.__class__(session, [], recordStore=right.recordStore)
                if query.boolean.value == 'prox':
                    # bitmaps can't do prox, so just raise
                    raise QueryException("Cannot use Prox with %s" % left.index.toCQL(), 18)
                elif query.boolean.value == 'not':
                    # can't reorder without changing query
                    return new.combine(session, [left, right], query, self)
                else:
                    return new.combine(session, [right, left], query, self)
            elif right.__class__ == BitmapResultSet:
                new = left.__class__(session, [], recordStore=left.recordStore)
            else:
                new = SimpleResultSet(session, [])
            rs = new.combine(session, [left, right], query, self)
            trip = cql.Triple()
            trip.leftOperand = left.query
            trip.rightOperand = right.query
            trip.boolean = query.boolean
            rs.query = trip
            return rs
Beispiel #4
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 def testExtend(self):
     "Test appending multiple item to a ResultSet"
     rs = SimpleResultSet(self.session)
     self.assertEqual(len(rs), 0)
     rs.extend([self.rsi1, self.rsi2])
     self.assertEqual(len(rs), 2)
     self.assertEqual(rs[0], self.rsi1)
     self.assertEqual(rs[1], self.rsi2)
Beispiel #5
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 def testFromList(self):
     "Test population of SimpleResultSet using fromList method."
     rs = SimpleResultSet(self.session)
     self.assertEqual(len(rs), 0)
     self.assertIsInstance(rs, SimpleResultSet)
     rs.fromList([self.rsi1, self.rsi3])
     for x, y in zip(self.a, rs):
         self.assertEqual(x, y)
Beispiel #6
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 def _deserialise(self, session, data, size, id_):
     data = data.decode('string_escape')
     fmt = '<' + 'l' * size
     ids = struct.unpack(fmt, data)
     # can't use bitfield, as need to preserve order
     rset = SimpleResultSet(session)
     items = [SimpleResultSetItem(session, x, resultSet=rset) for x in ids]
     rset.fromList(items)
     rset.id = id_
     return rset
Beispiel #7
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 def _deserialise(self, session, data, size, id):
     data = data.decode('string_escape')
     fmt = 'l' * size
     ids = struct.unpack(fmt, data)
     # can't use bitfield, as need to preserve order
     rset = SimpleResultSet(session)
     items = [SimpleResultSetItem(session, x, resultSet=rset) for x in ids]
     rset.fromList(items)
     rset.id = id
     return rset
Beispiel #8
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 def testCombineAll(self):
     "Test combining ResultSets with 'all'"
     # A clause / boolean is required to combine ResultSets
     clause = cqlparse('my.index all "foo"')
     # Create a new ResultSet to combine into 
     rs = SimpleResultSet(self.session)
     rs = rs.combine(self.session, [self.a, self.b], clause)
     # Check return value is a Resultset
     self.assertIsInstance(rs, SimpleResultSet)
     # Check merged ResultSet has 1 item
     self.assertEqual(len(rs), 1)
     # Check that merged ResultSet contains the correct item
     self.assertIn(self.rsi1, rs)
Beispiel #9
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    def search(self, session, query, db):
        # take CQL query and translate to Lucene
        pm = db.get_path(session, 'protocolMap')
        if not pm:
            db._cacheProtocolMaps(session)
            pm = db.protocolMaps.get('http://www.loc.gov/zing/srw/')
        query.config = pm
        lq = cqlToLucene(session, query, pm)
        q = self.parser.parse(lq)
        results = self.searcher.search(q, lucene.Sort.RELEVANCE)

        # now map to a ResultSet
        items = []
        for x in range(len(results)):
            hit = results[x]
            w = results.score(x)
            rsid = hit.getField('id').stringValue()
            (recStore, id) = rsid.split('/')
            if id.isdigit():
                id = int(id)
            rsi = SimpleResultSetItem(session, id, recStore, weight=w)
            items.append(rsi)

        rs = SimpleResultSet(session, items)
        return rs
Beispiel #10
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 def testInit(self):
     "Check initialization of ResultSet"
     rs = SimpleResultSet(self.session)
     # Check is instance of SimpleResultSet
     self.assertIsInstance(rs, SimpleResultSet)
     # Check is empty
     self.assertEqual(len(rs), 0)
 def _get_test_resultSets(self):
     for x in range(5):
         rs = SimpleResultSet(self.session)
         for y in range(5):
             occs = 5 - x
             rs.append(SimpleResultSetItem(self.session,
                                           id=y,
                                           recStore="recordStore",
                                           occs=occs,
                                           database="",
                                           diagnostic=None,
                                           weight=0.5,
                                           resultSet=None,
                                           numeric=None)
                       )
         yield rs
 def _get_test_resultSets(self):
     for x in range(5):
         rs = SimpleResultSet(self.session)
         for y in range(5):
             occs = 5 - x
             rs.append(
                 SimpleResultSetItem(self.session,
                                     id=y,
                                     recStore="recordStore",
                                     occs=occs,
                                     database="",
                                     diagnostic=None,
                                     weight=0.5,
                                     resultSet=None,
                                     numeric=None))
         yield rs
Beispiel #13
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 def testCombineAny(self):
     "Test combining ResultSets with 'any'"
     # A clause / boolean is required to combine ResultSets
     clause = cqlparse('my.index any "foo"')
     # Create a new ResultSet to combine into 
     rs = SimpleResultSet(self.session)
     rs = rs.combine(self.session, [self.a, self.b], clause)
     # Check return value is a Resultset
     self.assertIsInstance(rs, SimpleResultSet)
     # Check merged ResultSet contains each ResultSetItem
     self.assertIn(self.rsi1, rs)
     self.assertIn(self.rsi2, rs)
     self.assertIn(self.rsi3, rs)
     self.assertIn(self.rsi4, rs)
     # Check merged ResultSet has 3 items (as rsi1 and rsi2 are identical)
     self.assertEqual(len(rs), 3)
Beispiel #14
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    def setUp(self):
        """Setup some ResultsetItems and put them into ResultSets to evaluate.

        N.B. a == b, other pairs should not evaluate as equal
        """
        self.session = session = Session()
        # Set up same 4 ResultSetItems as for SimpleResultSetItemTestCase
        self.rsi1 = SimpleResultSetItem(session,
                                        id=0,
                                        recStore="recordStore",
                                        occs=5,
                                        database="",
                                        diagnostic=None,
                                        weight=0.5,
                                        resultSet=None,
                                        numeric=None)
        self.rsi2 = SimpleResultSetItem(session,
                                        id=0,
                                        recStore="recordStore",
                                        occs=3,
                                        database="",
                                        diagnostic=None,
                                        weight=0.5,
                                        resultSet=None,
                                        numeric=None)
        self.rsi3 = SimpleResultSetItem(session,
                                        id=1,
                                        recStore="recordStore",
                                        occs=1,
                                        database="",
                                        diagnostic=None,
                                        weight=0.5,
                                        resultSet=None,
                                        numeric=None)
        self.rsi4 = SimpleResultSetItem(session,
                                        id=0,
                                        recStore="recordStore2",
                                        occs=2,
                                        database="",
                                        diagnostic=None,
                                        weight=0.5,
                                        resultSet=None,
                                        numeric=None)
        # Put identical (rsi1 and rsi2) into separate ResultSets
        self.a = SimpleResultSet(session, [self.rsi1, self.rsi3], id="a")
        self.b = SimpleResultSet(session, [self.rsi2, self.rsi4], id="b")
Beispiel #15
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 def search(self, session, query, db):
     # Kludgey optimisation
     pm = db.get_path(session, 'protocolMap')
     if not pm:
         db._cacheProtocolMaps(session)
         pm = db.protocolMaps.get('http://www.loc.gov/zing/srw/')
         db.paths['protocolMap'] = pm
     query = self._cql_to_sql(session, query, pm)
     res = self._query(query)
     dr = res.dictresult()
     rset = SimpleResultSet([])
     rsilist = []
     for t in dr:
         (store, id) = t['recordid'].split('/', 1)
         item = SimpleResultSetItem(session, id, store, 1, resultSet=rset)
         rsilist.append(item)
     rset.fromList(rsilist)
     return rset
Beispiel #16
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 def search(self, session, query, db):
     # Kludgey optimisation
     pm = db.get_path(session, 'protocolMap')
     if not pm:
         db._cacheProtocolMaps(session)
         pm = db.protocolMaps.get('http://www.loc.gov/zing/srw/')
         db.paths['protocolMap'] = pm
     query = self._cql_to_sql(session, query, pm)
     res = self._query(query)
     dr = res.dictresult()
     rset = SimpleResultSet([])
     rsilist = []
     for t in dr:
         (store, id) = t['recordid'].split('/', 1)
         item = SimpleResultSetItem(session, id, store, 1, resultSet=rset)
         rsilist.append(item)
     rset.fromList(rsilist)
     return rset
Beispiel #17
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 def fetch_resultSet(self, session, id):
     data = self.fetch_data(session, id)
     if (data):
         (cl, srlz) = data.split('||', 1)
         rset = dynamic.buildObject(session, cl, [])
         rset.deserialise(session, srlz)
         return rset
     else:
         return SimpleResultSet(session, [], id)
Beispiel #18
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    def construct_resultSet(self, session, terms, queryHash={}):
        # in: res.dictresult()

        s = SimpleResultSet(session, [])
        rsilist = []
        for t in terms['records']:
            (store, id) = t['recordid'].split('/', 1)
            occs = t['occurences']
            item = SimpleResultSetItem(session, id, store, occs, resultSet=s)
            rsilist.append(item)
        s.fromList(rsilist)
        s.index = self
        if queryHash:
            s.queryTerm = queryHash['text']
            s.queryFreq = queryHash['occurences']
        s.totalRecs = terms['totalRecs']
        s.totalOccs = terms['totalOccs']
        return s
Beispiel #19
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 def testCori(self):
     "Test combining with CORI relevance ranking."
     # A clause / boolean is required to combine ResultSets
     clause = cqlparse('my.index all/rel.algorithm=cori "foo bar"')
     clause.addPrefix('rel', "info:srw/cql-context-set/2/relevance-1.2")
     # A Database is required for relevance ranking
     db = FakeDatabase(self.session, None)
     # A RecordStore is required for CORI score calculation
     recStore = FakeRecordStore(self.session, None)
     # Test self.a
     # Create a new ResultSet to combine into 
     rs = SimpleResultSet(self.session)
     rs = rs.combine(self.session, [self.a], clause, db)
     self.assertEqual(len(rs), 2)
     for rsi in rs:
         # Check that each ResultSetItem has a score (weight)
         self.assertTrue(hasattr(rsi, 'weight'))
         # Check that each ResultSetItem has a scaled score less than 1
         self.assertLessEqual(rsi.scaledWeight, 1.0)
     # Check scores are correct and in order
     matches = len(self.a)
     # I is used in calculating score for each item
     I = (math.log((db.totalItems + 0.5) / matches) /
          math.log(db.totalItems + 1.0))
     expectedScores = []
     for rsi in [self.rsi1, self.rsi3]:
         size = recStore.fetch_recordMetadata(self.session,
                                              rsi.id,
                                              'wordCount')
         T = (rsi.occurences /
              (rsi.occurences + 50.0 + (( 150.0 * size) / db.meanWordCount))
              )
         expectedScores.append(0.4 + (0.6 * T * I))
     self.assertListEqual([rsi.weight for rsi in rs], expectedScores)
     # Test self.b
     # Create a new ResultSet to combine into 
     rs = SimpleResultSet(self.session)
     rs = rs.combine(self.session, [self.b], clause, db)
     self.assertEqual(len(rs), 2)
     for rsi in rs:
         # Check that each ResultSetItem has a score (weight)
         self.assertTrue(hasattr(rsi, 'weight'))
         # Check that each ResultSetItem has a scaled score less than 1
         self.assertLessEqual(rsi.scaledWeight, 1.0)
     # Check scores are correct and in order
     matches = len(self.b)
     # I is used in calculating score for each item
     I = (math.log((db.totalItems + 0.5) / matches) /
          math.log(db.totalItems + 1.0))
     expectedScores = []
     for rsi in [self.rsi2, self.rsi4]:
         size = recStore.fetch_recordMetadata(self.session,
                                              rsi.id,
                                              'wordCount')
         T = (rsi.occurences /
              (rsi.occurences + 50.0 + (( 150.0 * size) / db.meanWordCount))
              )
         expectedScores.append(0.4 + (0.6 * T * I))
     self.assertListEqual([rsi.weight for rsi in rs], expectedScores)
Beispiel #20
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    def construct_resultSet(self, session, terms, queryHash={}):
        # in: res.dictresult()

        s = SimpleResultSet(session, [])
        rsilist = []
        for t in terms['records']:
            (store, id) = t['recordid'].split('/', 1)
            occs = t['occurences']
            item = SimpleResultSetItem(session, id, store, occs, resultSet=s)
            rsilist.append(item)
        s.fromList(rsilist)
        s.index = self
        if queryHash:
            s.queryTerm = queryHash['text']
            s.queryFreq = queryHash['occurences']
        s.totalRecs = terms['totalRecs']
        s.totalOccs = terms['totalOccs']
        return s
Beispiel #21
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 def testTfidf(self):
     "Test combining with TF-IDF relevance ranking."
     # A clause / boolean is required to combine ResultSets
     clause = cqlparse('my.index all/rel.algorithm=tfidf "foo bar"')
     clause.addPrefix('rel', "info:srw/cql-context-set/2/relevance-1.2")
     # A Database is required for relevance ranking
     db = FakeDatabase(self.session, None, parent=None)
     # Test self.a
     # Create a new ResultSet to combine into
     rs = SimpleResultSet(self.session)
     rs = rs.combine(self.session, [self.a], clause, db)
     self.assertEqual(len(rs), 2)
     for rsi in rs:
         # Check that each ResultSetItem has a score (weight)
         self.assertTrue(hasattr(rsi, 'weight'))
         # Check that each ResultSetItem has a scaled score less than 1
         self.assertLessEqual(rsi.scaledWeight, 1.0)
     # Check scores are correct and in order
     matches = len(self.a)
     self.assertListEqual([rsi.weight for rsi in rs],
                          [5 * math.log(db.totalItems / matches),
                           1 * math.log(db.totalItems / matches)]
                          )
     # Test self.b
     # Create a new ResultSet to combine into
     rs = SimpleResultSet(self.session)
     rs = rs.combine(self.session, [self.b], clause, db)
     self.assertEqual(len(rs), 2)
     for rsi in rs:
         # Check that each ResultSetItem has a score (weight)
         self.assertTrue(hasattr(rsi, 'weight'))
         # Check that each ResultSetItem has a scaled score less than 1
         self.assertLessEqual(rsi.scaledWeight, 1.0)
     # Check scores are correct and in order
     matches = len(self.b)
     self.assertListEqual([rsi.weight for rsi in rs],
                          [3 * math.log(db.totalItems / matches),
                           2 * math.log(db.totalItems / matches)]
                          )
Beispiel #22
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    def search(self, session, query):
        # Check for optimized indexStore based search (eg SQL translation)
        storeList = self.get_path(session, 'indexStoreList')
        if not storeList:
            indexStore = self.get_path(session, 'indexStore')
            if not indexStore:
                msg = ("No indexStore/indexStoreList associated with "
                       "database: %s" % self.id)
                raise ConfigFileException(msg)
            storeList = [indexStore.id]
        else:
            storeList = storeList.split(' ')
        # FIXME: Should respect multiple index stores somehow?
        idxStore = self.get_object(session, storeList[0])
        # Check if there's an indexStore specific search function
        if hasattr(idxStore, 'search'):
            return idxStore.search(session, query, self)
        else:
            if ((not hasattr(query, 'leftOperand'))
                    and query.relation.value == "any"):
                # Don't try to rewrite, futile.
                pass
            else:
                n = self._rewriteQuery(session, query)
                if n:
                    query = n
            if not hasattr(query, 'leftOperand'):
                # Single term or any in single clause
                query.resultCount = 1
                rs = self._search(session, query)
            else:
                # Triples... walk and look for ANDs that have a 0 length rs
                # Attach resultsets with counts
                self._attachResultCount(session, query)
                if query.resultCount == 0:
                    # no matches
                    return SimpleResultSet([])
                else:
                    rs = self._search(session, query)

        # now do top level stuff, like sort

        if rs.relevancy:
            rs.scale_weights()
            rs.order(session, "weight")
        elif query.sortKeys:
            # CQL 1.2 sort definition
            # URI: info:srw/cql-context-set/1/sort-v1.0

            sk = query.sortKeys
            sk.reverse()  # stable sort = keys in reverse order
            pm = self.get_path(session, 'protocolMap')
            if not pm:
                self._cacheProtocolMaps(session)
                pm = self.protocolMaps.get('http://www.loc.gov/zing/srw/')
                self.paths['protocolMap'] = pm
            for idx in sk:
                # resolve index
                index = pm.resolveIndex(session, query)
                # and find params from modifiers
                if idx['ascending']:
                    ascending = True
                elif idx['descending']:
                    ascending = False
                elif hasattr(pm, 'defaultSortDirection'):
                    ascending = pm.defaultSortDirection[:3].lower() == 'asc'
                else:
                    ascending = True

                if idx['missingomit']:
                    miss = 0
                elif idx['missinghigh']:
                    miss = 1
                elif idx['missinglow']:
                    miss = -1
                elif idx['missingfail']:
                    miss = cql.Diagnostic()
                elif idx['missingvalue']:
                    miss = idx['missingvalue'].value
                elif hasattr(pm, 'defaultSortMissing'):
                    m = pm.defaultSortMissing
                    vals = ['low', 'omit', 'high']
                    if m in vals:
                        miss = int(vals.index(m)) - 1
                    elif m == 'fail':
                        miss = cql.Diagnostic()
                    else:
                        miss = m
                else:
                    miss = [-1, 1][int(ascending)]

                if idx['respectcase']:
                    case = 1
                elif idx['ignorecase']:
                    case = 0
Beispiel #23
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 def _search(self, session, query):
     if query.resultCount == 0:
         # No matches in this full subtree
         return SimpleResultSet([])
     else:
         return SimpleDatabase._search(self, session, query)
Beispiel #24
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    def _listResults(self, metadataPrefix, set_=None, from_=None, until=None):
        """Return a list of (datestamp, resultSet) tuples.

        Suitable for use by:
            - listIdentifiers
            - listRecords
        """
        session = self.session
        # Check set value
        if set_ and not set_.startswith('contributor:'):
            raise StopIteration
        elif set_:
            set_ = set_.split(':', 1)[-1]

        if until and until < self.earliestDatestamp:
            raise BadArgumentError('until argument value is earlier than '
                                   'earliestDatestamp.')
        if not from_:
            from_ = self.earliestDatestamp
        if not until:
            until = datetime.datetime.now()
            #(from_ < self.earliestDatestamp)
        if (until < from_):
            raise BadArgumentError('until argument value is earlier than from '
                                   'argument value.')
        q = cqlparse('rec.lastModificationDate > "%s" and '
                     'rec.lastModificationDate < "%s"' % (from_, until)
                     )
        # Actually need datestamp values as well as results - interact with
        # indexes directly for efficiency
        # Get CQL ProtocolMap
        pm = self.db.get_path(session, 'protocolMap')
        idx = pm.resolveIndex(session, q.leftOperand)
        q.config = pm
        res = {}
        for src in idx.sources[u'data']:
            res.update(src[1].process(session, [[str(from_)]]))
            res.update(src[1].process(session, [[str(until)]]))
        from_ = min(res.keys())
        until = max(res.keys())
        # Tweak until value to make it inclusive
        until = until[:-1] + chr(ord(until[-1]) + 1)
        termList = idx.fetch_termList(session, from_, 0, '>=', end=until)
        # Generate sequence of datestamp, resultSet tuples
        for t in termList:
            try:
                datetime_obj = datetime.datetime.strptime(
                    t[0],
                    u'%Y-%m-%dT%H:%M:%S'
                )
            except ValueError:
                datetime_obj = datetime.datetime.strptime(
                    t[0],
                    u'%Y-%m-%d %H:%M:%S'
                )
            datetime_rs = idx.construct_resultSet(session, t[1])
            if not set_:
                yield (datetime_obj, datetime_rs)
            else:
                # Filter by set
                set_q = cqlparse('vdb.identifier = {0}'.format(set_))
                set_rs = self.db.search(session, set_q)
                full_rs = SimpleResultSet(session)
                full_q = cqlparse('{0} and {1}'
                                  ''.format(q.toCQL(), set_q.toCQL()))
                yield (datetime_obj, full_rs.combine(session,
                                                     [datetime_rs, set_rs],
                                                     full_q
                                                     )
                       )
Beispiel #25
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    def testOkapi(self):
        "Test combining with OKAPI BM-25 relevance ranking."
        # A clause / boolean is required to combine ResultSets
        b, k1, k3 = [0.75, 1.5, 1.5]
        clause = cqlparse('my.index all/rel.algorithm=okapi/'
                          'rel.const0={0}/'
                          'rel.const1={1}/'
                          'rel.const2={2}'
                          ' "foo bar"'.format(b, k1, k3))
        clause.addPrefix('rel', "info:srw/cql-context-set/2/relevance-1.2")
        # A Database is required for relevance ranking
        db = FakeDatabase(self.session, None)
        # A RecordStore is required for CORI score calculation
        recStore = FakeRecordStore(self.session, None)
        # Test self.a
        # Create a new ResultSet to combine into 
        rs = SimpleResultSet(self.session)
        # Set ResultSet queryFrequency - required for OKAPI BM-25
        self.a.queryFreq = 1
        rs = rs.combine(self.session, [self.a], clause, db)
        self.assertEqual(len(rs), 2)
        for rsi in rs:
            # Check that each ResultSetItem has a score (weight)
            self.assertTrue(hasattr(rsi, 'weight'))
#            self.assertTrue(rsi.weight)
            # Check that each ResultSetItem has a scaled score less than 1
            self.assertLessEqual(rsi.scaledWeight, 1.0)
        # Check scores are correct and in order
        matches = len(self.a)
        idf = math.log(db.totalItems / matches)
        qtw = ((k3 + 1) * 1) / (k3 + 1)
        expectedScores = []
        for rsi in [self.rsi1, self.rsi3]:
            size = recStore.fetch_recordMetadata(self.session,
                                                 rsi.id,
                                                 'wordCount')
            T = (((k1 + 1) * rsi.occurences) /
                 ((k1 * ((1 - b) + b *
                         (size / db.meanWordCount)
                         )
                   ) +
                  rsi.occurences)
                 )
            expectedScores.append(idf * T * qtw)
        self.assertListEqual([rsi.weight for rsi in rs], expectedScores)
        # Test self.b
        # Create a new ResultSet to combine into 
        rs = SimpleResultSet(self.session)
        # Set ResultSet queryFrequency - required for OKAPI BM-25
        self.b.queryFreq = 1
        rs = rs.combine(self.session, [self.b], clause, db)
        self.assertEqual(len(rs), 2)
        for rsi in rs:
            # Check that each ResultSetItem has a score (weight)
            self.assertTrue(hasattr(rsi, 'weight'))
#            self.assertTrue(rsi.weight)
            # Check that each ResultSetItem has a scaled score less than 1
            self.assertLessEqual(rsi.scaledWeight, 1.0)
        # Check scores are correct and in order
        matches = len(self.a)
        idf = math.log(db.totalItems / matches)
        qtw = ((k3 + 1) * 1) / (k3 + 1)
        expectedScores = []
        for rsi in [self.rsi2, self.rsi4]:
            size = recStore.fetch_recordMetadata(self.session,
                                                 rsi.id,
                                                 'wordCount')
            T = (((k1 + 1) * rsi.occurences) /
                 ((k1 * ((1 - b) + b *
                         (size / db.meanWordCount)
                         )
                   ) +
                  rsi.occurences)
                 )
            expectedScores.append(idf * T * qtw)
        self.assertListEqual([rsi.weight for rsi in rs], expectedScores)