matthias
/
xapian-haystack
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Simplified construction of Xapian queries.

This commit is contained in:
Jorge C. Leitão 2014-05-17 16:54:21 +02:00
parent 5d16d1aca7
commit d06da45d9d
1 changed files with 23 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

49
xapian_backend.py
View File

@ -1114,10 +1114,9 @@ class XapianSearchQuery(BaseSearchQuery):
with positional order.
"""
if ' ' in term:
query = self._phrase_query(term.split(), field_name)
query = self._phrase_query(term.split(), field_name, field_type)
else:
query = self._term_query(term, field_name, field_type, exact=True)
query = self._term_query(term, field_name, field_type, exact=True, stemmed=False)
if is_not:
return xapian.Query(xapian.Query.OP_AND_NOT, self._all_query(), query)
else:
@ -1146,33 +1145,31 @@ class XapianSearchQuery(BaseSearchQuery):
term_list = [self._term_query(term, field, field_type, exact) for term in term_list]
return xapian.Query(xapian.Query.OP_OR, term_list)
def _phrase_query(self, term_list, field_name):
def _phrase_query(self, term_list, field_name, field_type):
"""
Returns a query that matches exact terms and with
Returns a query that matches exact terms with
positional order (i.e. ["this", "thing"] != ["thing", "this"])
and no stem.
If `field_name` is given, this match is restricted to the field.
If `field_name` is not `None`, restrict to the field.
"""
prefix = ''
if field_name in ('id', 'django_id', 'django_ct'):
prefix = TERM_PREFIXES[field_name]
elif field_name:
prefix = TERM_PREFIXES['field']
term_list = [self._term_query(term, field_name, field_type,
stemmed=False) for term in term_list]
if field_name:
term_list = ['%s%s%s' % (prefix,
field_name.upper(),
term) for term in term_list]
query = xapian.Query(xapian.Query.OP_PHRASE, term_list)
return query
return xapian.Query(xapian.Query.OP_PHRASE, term_list)
def _term_query(self, term, field_name, field_type, exact=False):
def _term_query(self, term, field_name, field_type, exact=False, stemmed=True):
"""
Constructs a query of a single term.
If `field_name` is not `None`, the term is search on that field only.
If exact is `True`, the search is restricted to non-stemmed boolean match.
If exact is `True`, the search is restricted to boolean matches.
"""
# using stemmed terms in exact query is not acceptable.
if stemmed:
assert not exact
if field_name in ('id', 'django_id', 'django_ct'):
# to ensure the value is serialized correctly.
if field_name == 'django_id':
@ -1191,17 +1188,17 @@ class XapianSearchQuery(BaseSearchQuery):
prefix = TERM_PREFIXES['field'] + field_name.upper()
term = _marshal_value(term)
unstemmed = constructor.format(prefix=prefix, term=term)
if exact:
return xapian.Query(unstemmed)
else:
unstemmed_term = constructor.format(prefix=prefix, term=term)
if stemmed:
stem = xapian.Stem(self.backend.language)
stemmed = 'Z' + constructor.format(prefix=prefix, term=stem(term))
stemmed_term = 'Z' + constructor.format(prefix=prefix, term=stem(term))
return xapian.Query(xapian.Query.OP_OR,
xapian.Query(stemmed),
xapian.Query(unstemmed)
xapian.Query(stemmed_term),
xapian.Query(unstemmed_term)
)
else:
return unstemmed_term
def _filter_gt(self, term, field, is_not):
return self._filter_lte(term, field, is_not=not is_not)