def test_expressions(self):
self.assertEqual(
repr(Case(When(a=1))),
"<Case: CASE WHEN <Q: (AND: ('a', 1))> THEN Value(None), ELSE Value(None)>"
)
self.assertEqual(repr(Col('alias', 'field')), "Col(alias, field)")
self.assertEqual(repr(Date('published', 'exact')),
"Date(published, exact)")
self.assertEqual(repr(DateTime('published', 'exact', utc)),
"DateTime(published, exact, %s)" % utc)
self.assertEqual(repr(F('published')), "F(published)")
self.assertEqual(repr(F('cost') + F('tax')),
"<CombinedExpression: F(cost) + F(tax)>")
self.assertEqual(
repr(ExpressionWrapper(
F('cost') + F('tax'), models.IntegerField())),
"ExpressionWrapper(F(cost) + F(tax))")
self.assertEqual(repr(Func('published', function='TO_CHAR')),
"Func(F(published), function=TO_CHAR)")
self.assertEqual(repr(OrderBy(Value(1))),
'OrderBy(Value(1), descending=False)')
self.assertEqual(repr(Random()), "Random()")
self.assertEqual(repr(RawSQL('table.col', [])),
"RawSQL(table.col, [])")
self.assertEqual(repr(Ref('sum_cost', Sum('cost'))),
"Ref(sum_cost, Sum(F(cost)))")
self.assertEqual(repr(Value(1)), "Value(1)")
def _get_select(self, col, lookup_type):
return Date(col, lookup_type)
def time_series(qs,
date_field,
aggregate,
interval,
date_from=None,
date_to=None):
current_timezone = timezone.get_current_timezone()
is_date = interval in DATE_SERIES
if isinstance(qs.model._meta.get_field(date_field), models.DateTimeField):
db_interval = DateTime(date_field, interval, current_timezone)
else:
db_interval = Date(date_field, interval)
if not isinstance(aggregate, dict):
aggregate = {'aggregate': aggregate}
SeriesRecord = namedtuple('SeriesRecord',
['time_value'] + aggregate.keys())
if is_date:
if date_from and not isinstance(date_from, datetime):
date_from = current_timezone.localize(
datetime.combine(date_from, time.min))
if date_to and not isinstance(date_to, datetime):
date_to = current_timezone.localize(
datetime.combine(date_to, time.max))
if date_from is not None:
qs = qs.filter(**{date_field + '__gte': date_from})
if date_to is not None:
qs = qs.filter(**{date_field + '__lte': date_to})
qs = (qs.annotate(time_value=db_interval).values_list(
'time_value').order_by('time_value').annotate(**aggregate))
def convert_date(val):
if is_date and isinstance(val, datetime):
return val.date()
return val
records = [SeriesRecord(convert_date(val[0]), *val[1:]) for val in qs]
if len(records):
date_from = date_from or records[0].time_value
date_to = date_to or records[-1].time_value
empty_record = partial(SeriesRecord, **{k: None for k in aggregate.keys()})
return fill_time_series_gap(records, empty_record, interval, date_from,
date_to)
# example:
#
# time_series(
# User.objects.all(),
# date_field='date_joined',
# aggregate={'count': Count('id')},
# interval='day',
# date_to=timezone.localtime(timezone.now()).date()
# )
#
# [SeriesRecord(time_value=datetime.date(2015, 9, 17), count=10),
# SeriesRecord(time_value=datetime.date(2015, 9, 18), count=None),
# SeriesRecord(time_value=datetime.date(2015, 9, 19), count=None),
# ...
