def _create_query_for_field(self, field, value, analyzer=None):
"""generate a field query
this functions creates a field->value query
:param field: The fieldname to be used
:type field: str
:param value: The wanted value of the field
:type value: str
:param analyzer: The analyzer to be used
Possible analyzers are:
- :attr:`CommonDatabase.ANALYZER_TOKENIZE`
the field value is splitted to be matched word-wise
- :attr:`CommonDatabase.ANALYZER_PARTIAL`
the field value must start with the query string
- :attr:`CommonDatabase.ANALYZER_EXACT`
keep special characters and the like
:type analyzer: bool
:return: resulting query object
:rtype: PyLucene.Query
"""
if analyzer is None:
analyzer = self.analyzer
if analyzer == self.ANALYZER_EXACT:
analyzer_obj = PyLucene.KeywordAnalyzer()
else:
value = self._escape_term_value(value)
analyzer_obj = PyLucene.StandardAnalyzer()
qp = PyLucene.QueryParser(field, analyzer_obj)
if (analyzer & self.ANALYZER_PARTIAL > 0):
# PyLucene uses explicit wildcards for partial matching
value += "*"
return qp.parse(value)
def _create_query_for_string(self, text, require_all=True,
analyzer=None):
"""generate a query for a plain term of a string query
basically this function parses the string and returns the resulting
query
@param text: the query string
@type text: str
@param require_all: boolean operator
(True -> AND (default) / False -> OR)
@type require_all: bool
@param analyzer: the analyzer to be used
possible analyzers are:
- L{CommonDatabase.ANALYZER_TOKENIZE}
the field value is splitted to be matched word-wise
- L{CommonDatabase.ANALYZER_PARTIAL}
the field value must start with the query string
- L{CommonDatabase.ANALYZER_EXACT}
keep special characters and the like
@type analyzer: bool
@return: resulting query object
@rtype: PyLucene.Query
"""
if analyzer is None:
analyzer = self.analyzer
if analyzer == self.ANALYZER_EXACT:
analyzer_obj = PyLucene.KeywordAnalyzer()
else:
text = _escape_term_value(text)
analyzer_obj = PyLucene.StandardAnalyzer()
qp = PyLucene.QueryParser(UNNAMED_FIELD_NAME, analyzer_obj)
if (analyzer & self.ANALYZER_PARTIAL > 0):
# PyLucene uses explicit wildcards for partial matching
text += "*"
if require_all:
qp.setDefaultOperator(qp.Operator.AND)
else:
qp.setDefaultOperator(qp.Operator.OR)
return qp.parse(text)
