Я пытаюсь применить частичный поиск в Django postgres, точно так же, как описано здесь django -text-search-with-partial-sentence-match Я нашел там довольно хорошее решение
from psycopg2.extensions import adapt
from django.contrib.postgres.search import SearchQuery
class PrefixedPhraseQuery(SearchQuery):
"""
Alter the tsquery executed by SearchQuery
"""
def as_sql(self, compiler, connection):
# Or <-> available in Postgres 9.6
value = adapt('%s:*' % ' & '.join(self.value.split()))
if self.config:
config_sql, config_params = compiler.compile(self.config)
template = 'to_tsquery({}::regconfig, {})'\
.format(config_sql, value)
params = config_params
else:
template = 'to_tsquery({})'\
.format(value)
params = []
if self.invert:
template = '!!({})'.format(template)
return template, params
Он отлично работает для Python 3.6, но не работает для 3.9. Разница в том, что в 3.6 SearchQuery наследуется от Value:
class SearchQuery(SearchQueryCombinable, Value):
output_field = SearchQueryField()
SEARCH_TYPES = {
'plain': 'plainto_tsquery',
'phrase': 'phraseto_tsquery',
'raw': 'to_tsquery',
}
def __init__(self, value, output_field=None, *, config=None, invert=False, search_type='plain'):
self.config = config
self.invert = invert
if search_type not in self.SEARCH_TYPES:
raise ValueError("Unknown search_type argument '%s'." % search_type)
self.search_type = search_type
super().__init__(value, output_field=output_field)
а в Python 3.9 SearchQuery наследуется от Func:
class SearchQuery(SearchQueryCombinable, Func):
output_field = SearchQueryField()
SEARCH_TYPES = {
'plain': 'plainto_tsquery',
'phrase': 'phraseto_tsquery',
'raw': 'to_tsquery',
'websearch': 'websearch_to_tsquery',
}
def __init__(self, value, output_field=None, *, config=None, invert=False, search_type='plain'):
self.function = self.SEARCH_TYPES.get(search_type)
if self.function is None:
raise ValueError("Unknown search_type argument '%s'." % search_type)
if not hasattr(value, 'resolve_expression'):
value = Value(value)
expressions = (value,)
self.config = SearchConfig.from_parameter(config)
if self.config is not None:
expressions = (self.config,) + expressions
self.invert = invert
super().__init__(*expressions, output_field=output_field)
В Func, в отличие от Value, нет self.value
class Func(SQLiteNumericMixin, Expression):
"""An SQL function call."""
function = None
template = '%(function)s(%(expressions)s)'
arg_joiner = ', '
arity = None # The number of arguments the function accepts.
def __init__(self, *expressions, output_field=None, **extra):
if self.arity is not None and len(expressions) != self.arity:
raise TypeError(
"'%s' takes exactly %s %s (%s given)" % (
self.__class__.__name__,
self.arity,
"argument" if self.arity == 1 else "arguments",
len(expressions),
)
)
super().__init__(output_field=output_field)
self.source_expressions = self._parse_expressions(*expressions)
self.extra = extra
и значение выглядит так
class Value(Expression):
"""Represent a wrapped value as a node within an expression."""
def __init__(self, value, output_field=None):
"""
Arguments:
* value: the value this expression represents. The value will be
added into the sql parameter list and properly quoted.
* output_field: an instance of the model field type that this
expression will return, such as IntegerField() or CharField().
"""
super().__init__(output_field=output_field)
self.value = value
Кто-нибудь помог мне настроить образец кода на python 3.9 или порекомендовал какое-либо решение для аналогичного поиска?
