f7fac976d8
https://datastax-oss.atlassian.net/browse/PYTHON-288 Add Python 2.6 compliancy: - Remove dict/set comprehensions. - Use cassandra's OrderedDict. - Replace str.format() implicit placeholders ('{}') with explicit ones ('{0} {1} ...'). - Implement cqlengine.functions.get_total_seconds() as alternative to timedelta.total_seconds(). cqlengine integration tests remain to be backported.
100 lines
2.6 KiB
Python
100 lines
2.6 KiB
Python
# Copyright 2015 DataStax, Inc.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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from cassandra.cqlengine import UnicodeMixin
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class QueryOperatorException(Exception):
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pass
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class BaseQueryOperator(UnicodeMixin):
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# The symbol that identifies this operator in kwargs
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# ie: colname__<symbol>
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symbol = None
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# The comparator symbol this operator uses in cql
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cql_symbol = None
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def __unicode__(self):
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if self.cql_symbol is None:
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raise QueryOperatorException("cql symbol is None")
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return self.cql_symbol
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@classmethod
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def get_operator(cls, symbol):
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if cls == BaseQueryOperator:
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raise QueryOperatorException("get_operator can only be called from a BaseQueryOperator subclass")
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if not hasattr(cls, 'opmap'):
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cls.opmap = {}
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def _recurse(klass):
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if klass.symbol:
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cls.opmap[klass.symbol.upper()] = klass
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for subklass in klass.__subclasses__():
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_recurse(subklass)
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pass
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_recurse(cls)
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try:
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return cls.opmap[symbol.upper()]
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except KeyError:
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raise QueryOperatorException("{0} doesn't map to a QueryOperator".format(symbol))
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class BaseWhereOperator(BaseQueryOperator):
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""" base operator used for where clauses """
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class EqualsOperator(BaseWhereOperator):
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symbol = 'EQ'
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cql_symbol = '='
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class InOperator(EqualsOperator):
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symbol = 'IN'
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cql_symbol = 'IN'
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class GreaterThanOperator(BaseWhereOperator):
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symbol = "GT"
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cql_symbol = '>'
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class GreaterThanOrEqualOperator(BaseWhereOperator):
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symbol = "GTE"
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cql_symbol = '>='
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class LessThanOperator(BaseWhereOperator):
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symbol = "LT"
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cql_symbol = '<'
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class LessThanOrEqualOperator(BaseWhereOperator):
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symbol = "LTE"
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cql_symbol = '<='
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class BaseAssignmentOperator(BaseQueryOperator):
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""" base operator used for insert and delete statements """
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class AssignmentOperator(BaseAssignmentOperator):
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cql_symbol = "="
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class AddSymbol(BaseAssignmentOperator):
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cql_symbol = "+"
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