48 lines
1.7 KiB
Python
48 lines
1.7 KiB
Python
|
from django.core.exceptions import FullResultSet
|
||
|
|
from django.db.models.expressions import OrderByList
|
||
|
|
|
||
|
|
|
||
|
|
class OrderableAggMixin:
|
||
|
|
def __init__(self, *expressions, ordering=(), **extra):
|
||
|
|
if not ordering:
|
||
|
|
self.order_by = None
|
||
|
|
elif isinstance(ordering, (list, tuple)):
|
||
|
|
self.order_by = OrderByList(*ordering)
|
||
|
|
else:
|
||
|
|
self.order_by = OrderByList(ordering)
|
||
|
|
super().__init__(*expressions, **extra)
|
||
|
|
|
||
|
|
def resolve_expression(self, *args, **kwargs):
|
||
|
|
if self.order_by is not None:
|
||
|
|
self.order_by = self.order_by.resolve_expression(*args, **kwargs)
|
||
|
|
return super().resolve_expression(*args, **kwargs)
|
||
|
|
|
||
|
|
def get_source_expressions(self):
|
||
|
|
return super().get_source_expressions() + [self.order_by]
|
||
|
|
|
||
|
|
def set_source_expressions(self, exprs):
|
||
|
|
*exprs, self.order_by = exprs
|
||
|
|
return super().set_source_expressions(exprs)
|
||
|
|
|
||
|
|
def as_sql(self, compiler, connection):
|
||
|
|
*source_exprs, filtering_expr, ordering_expr = self.get_source_expressions()
|
||
|
|
|
||
|
|
order_by_sql = ""
|
||
|
|
order_by_params = []
|
||
|
|
if ordering_expr is not None:
|
||
|
|
order_by_sql, order_by_params = compiler.compile(ordering_expr)
|
||
|
|
|
||
|
|
filter_params = []
|
||
|
|
if filtering_expr is not None:
|
||
|
|
try:
|
||
|
|
_, filter_params = compiler.compile(filtering_expr)
|
||
|
|
except FullResultSet:
|
||
|
|
pass
|
||
|
|
|
||
|
|
source_params = []
|
||
|
|
for source_expr in source_exprs:
|
||
|
|
source_params += compiler.compile(source_expr)[1]
|
||
|
|
|
||
|
|
sql, _ = super().as_sql(compiler, connection, ordering=order_by_sql)
|
||
|
|
return sql, (*source_params, *order_by_params, *filter_params)
|