Source code for django.contrib.postgres.aggregates.general
import json
import warnings
from django.contrib.postgres.fields import ArrayField
from django.db.models import Aggregate, BooleanField, JSONField, TextField, Value
from django.utils.deprecation import RemovedInDjango50Warning, RemovedInDjango51Warning
from .mixins import OrderableAggMixin
__all__ = [
"ArrayAgg",
"BitAnd",
"BitOr",
"BitXor",
"BoolAnd",
"BoolOr",
"JSONBAgg",
"StringAgg",
]
# RemovedInDjango50Warning
NOT_PROVIDED = object()
class DeprecatedConvertValueMixin:
def __init__(self, *expressions, default=NOT_PROVIDED, **extra):
if default is NOT_PROVIDED:
default = None
self._default_provided = False
else:
self._default_provided = True
super().__init__(*expressions, default=default, **extra)
def resolve_expression(self, *args, **kwargs):
resolved = super().resolve_expression(*args, **kwargs)
if not self._default_provided:
resolved.empty_result_set_value = getattr(
self, "deprecation_empty_result_set_value", self.deprecation_value
)
return resolved
def convert_value(self, value, expression, connection):
if value is None and not self._default_provided:
warnings.warn(self.deprecation_msg, category=RemovedInDjango50Warning)
return self.deprecation_value
return value
[docs]class ArrayAgg(DeprecatedConvertValueMixin, OrderableAggMixin, Aggregate):
function = "ARRAY_AGG"
template = "%(function)s(%(distinct)s%(expressions)s %(ordering)s)"
allow_distinct = True
# RemovedInDjango50Warning
deprecation_value = property(lambda self: [])
deprecation_msg = (
"In Django 5.0, ArrayAgg() will return None instead of an empty list "
"if there are no rows. Pass default=None to opt into the new behavior "
"and silence this warning or default=[] to keep the previous behavior."
)
@property
def output_field(self):
return ArrayField(self.source_expressions[0].output_field)
[docs]class JSONBAgg(DeprecatedConvertValueMixin, OrderableAggMixin, Aggregate):
function = "JSONB_AGG"
template = "%(function)s(%(distinct)s%(expressions)s %(ordering)s)"
allow_distinct = True
output_field = JSONField()
# RemovedInDjango50Warning
deprecation_value = "[]"
deprecation_empty_result_set_value = property(lambda self: [])
deprecation_msg = (
"In Django 5.0, JSONBAgg() will return None instead of an empty list "
"if there are no rows. Pass default=None to opt into the new behavior "
"and silence this warning or default=[] to keep the previous "
"behavior."
)
# RemovedInDjango51Warning: When the deprecation ends, remove __init__().
#
# RemovedInDjango50Warning: When the deprecation ends, replace with:
# def __init__(self, *expressions, default=None, **extra):
def __init__(self, *expressions, default=NOT_PROVIDED, **extra):
super().__init__(*expressions, default=default, **extra)
if (
isinstance(default, Value)
and isinstance(default.value, str)
and not isinstance(default.output_field, JSONField)
):
value = default.value
try:
decoded = json.loads(value)
except json.JSONDecodeError:
warnings.warn(
"Passing a Value() with an output_field that isn't a JSONField as "
"JSONBAgg(default) is deprecated. Pass default="
f"Value({value!r}, output_field=JSONField()) instead.",
stacklevel=2,
category=RemovedInDjango51Warning,
)
self.default.output_field = self.output_field
else:
self.default = Value(decoded, self.output_field)
warnings.warn(
"Passing an encoded JSON string as JSONBAgg(default) is "
f"deprecated. Pass default={decoded!r} instead.",
stacklevel=2,
category=RemovedInDjango51Warning,
)
[docs]class StringAgg(DeprecatedConvertValueMixin, OrderableAggMixin, Aggregate):
function = "STRING_AGG"
template = "%(function)s(%(distinct)s%(expressions)s %(ordering)s)"
allow_distinct = True
output_field = TextField()
# RemovedInDjango50Warning
deprecation_value = ""
deprecation_msg = (
"In Django 5.0, StringAgg() will return None instead of an empty "
"string if there are no rows. Pass default=None to opt into the new "
'behavior and silence this warning or default="" to keep the previous behavior.'
)
def __init__(self, expression, delimiter, **extra):
delimiter_expr = Value(str(delimiter))
super().__init__(expression, delimiter_expr, **extra)