def test_many_to_many_fields_not_supported(self, migration_apps):
"""
Test that if an item in the yaml includes a many-to-many field,
the function raises NotImplementedError as this is not supported yet.
"""
yaml_content = """
- model: datahub.core.test.support.book
pk: 1
fields:
name: name
authors:
- 1
- 2
published_on: '2010-01-01'
"""
mocked_read = mock.mock_open(read_data=yaml_content)
PersonFactory.create_batch(2, pk=factory.Iterator([1, 2]))
with pytest.raises(NotImplementedError) as excinfo:
with mock.patch('datahub.core.migration_utils.open',
mocked_read,
create=True):
load_yaml_data_in_migration(migration_apps,
'path-to-file.yaml')
assert str(excinfo.value) == 'Many-to-many fields not supported'
def test_with_default_outer_field(self, expression):
"""
Test that a Person query set can annotated with the name of the most
recently published book.
This considers a single many-to-one relationship between Book and Person.
"""
person = PersonFactory()
book_data = [
{'name': 'oldest', 'published_on': date(2010, 1, 1)},
{'name': 'in the middle', 'published_on': date(2013, 1, 1)},
{'name': 'newest', 'published_on': date(2015, 1, 1)},
]
shuffle(book_data)
for item_data in book_data:
BookFactory(
proofreader=person,
authors=[],
**item_data,
)
queryset = Person.objects.annotate(
name_of_latest_book=get_top_related_expression_subquery(
Book.proofreader.field, expression, ('-published_on',),
),
)
assert queryset.first().name_of_latest_book == 'newest'
def test_ignores_blank_first_name(self):
"""Tests that a blank first_name is ignored."""
person = PersonFactory(first_name='')
queryset = Person.objects.annotate(
name=get_full_name_expression(),
)
assert queryset.first().name == person.last_name
def test_aggregates_as_array(self, names, distinct):
"""
Test that the first names of all authors for each book can be aggregated into an array
for various cases, and with distinct on and off.
"""
authors = PersonFactory.create_batch(
len(names),
first_name=factory.Iterator(
sample(names, len(names)),
),
)
BookFactory(authors=authors)
queryset = Book.objects.annotate(
author_names=get_array_agg_subquery(
Book.authors.through,
'book',
'person__first_name',
distinct=distinct,
),
)
actual_author_names = queryset.first().author_names
if distinct:
assert Counter(actual_author_names) == Counter(set(names))
else:
assert Counter(actual_author_names) == Counter(names)
def test_as_annotation(self):
"""Test that the function can be used as an annotation."""
person = PersonFactory()
queryset = Person.objects.annotate(data=JSONBBuildObject(
first_name='first_name', last_name='last_name'), )
assert queryset.first().data == {
'first_name': person.first_name,
'last_name': person.last_name,
}
def test_get_empty_string_if_null_expression(value, expected):
"""Tests if None can be replaced with an empty string."""
PersonFactory()
query = Person.objects.annotate(
possibly_null_value=Value(value, output_field=CharField(null=True)),
some_property=get_empty_string_if_null_expression('possibly_null_value'),
).values('some_property')
person = query.first()
assert person['some_property'] == expected
def test_full_name_annotation(self, include_country, country):
"""Tests that a Person query set can be annotated with full names."""
person = PersonFactory(country=country)
bracketed_field_name = 'country' if include_country else None
queryset = Person.objects.annotate(name=get_full_name_expression(
bracketed_field_name=bracketed_field_name), )
expected_name = f'{person.first_name} {person.last_name}'
if country and include_country:
expected_name += f' ({person.country})'
assert queryset.first().name == expected_name
def test_get_string_agg_subquery(num_authors):
"""
Test that get_string_agg_subquery() can be used to concatenate the first names of
all authors for each book into one field.
"""
authors = PersonFactory.create_batch(num_authors)
BookFactory(authors=authors)
queryset = Book.objects.annotate(author_names=get_string_agg_subquery(
Book, 'authors__first_name'), )
author_names_str = queryset.first().author_names
actual_author_names = sorted(
author_names_str.split(', ')) if author_names_str else []
expected_author_names = sorted(author.first_name for author in authors)
assert actual_author_names == expected_author_names
def test_with_max_aggregate_expression(self, num_books):
"""
Test that Max() can be used to calculate the maximum published-on date for the books a
person has proofread.
"""
proofreader = PersonFactory()
books = BookFactory.create_batch(num_books, proofreader=proofreader)
queryset = Person.objects.annotate(
max_published=get_aggregate_subquery(Person, Max('proofread_books__published_on')),
).filter(
pk=proofreader.pk,
)
actual_max_published = queryset.first().max_published
expected_max_published = max(book.published_on for book in books) if num_books else None
assert actual_max_published == expected_max_published
def test_can_annotate_queryset(self, names, distinct, expected_result):
"""
Test that the first names of all authors for each book can be concatenated into
one field as a query set annotation for various cases.
"""
authors = PersonFactory.create_batch(
len(names),
first_name=factory.Iterator(
sample(names, len(names)),
),
)
BookFactory(authors=authors)
queryset = Book.objects.annotate(
author_names=get_string_agg_subquery(Book, 'authors__first_name', distinct=distinct),
)
actual_author_names = queryset.first().author_names
assert actual_author_names == expected_result
def test_orders_results_when_ordering_specified(self, ordering,
expected_names):
"""Test that the values are ordered corrected when an ordering is specified."""
names = ['Barbara', 'Claire', 'Samantha']
authors = PersonFactory.create_batch(
len(names),
first_name=factory.Iterator(sample(names, len(names)), ),
)
BookFactory(authors=authors)
queryset = Book.objects.annotate(author_names=get_array_agg_subquery(
Book.authors.through,
'book',
'person__first_name',
ordering=ordering,
), )
actual_author_names = queryset.first().author_names
assert actual_author_names == expected_names
def test_aggregates_as_filtered_array(self, names, desired_names):
"""
Test that the desired first names of authors for each book can be aggregated into an array
for various cases.
"""
authors = PersonFactory.create_batch(
len(names),
first_name=factory.Iterator(sample(names, len(names)), ),
)
BookFactory(authors=authors)
queryset = Book.objects.annotate(author_names=get_array_agg_subquery(
Book.authors.through,
'book',
'person__first_name',
filter=Q(person__first_name__in=desired_names),
), )
actual_author_names = queryset.first()
assert set(actual_author_names.author_names) == set(desired_names)
def test_with_no_related_objects(self):
"""
Test that, if a Person query set is annotated with the name of the most
recently published proofread books, and there are no such books, the annotation
value is None.
This considers a single many-to-one relationship between Book and Person.
"""
created_person = PersonFactory()
queryset = Person.objects.annotate(
name_of_latest_book=get_top_related_expression_subquery(
Book.proofreader.field,
'name',
('-published_on', ),
), )
returned_person = queryset.first()
assert returned_person == created_person
assert returned_person.name_of_latest_book is None
def test_annotation(
self,
first_name,
last_name,
country,
fields,
bracketed_field,
expected_value,
):
"""
Tests that a Person query set can be annotated using get_bracketed_concat_expression().
"""
PersonFactory(first_name=first_name, last_name=last_name, country=country)
queryset = Person.objects.annotate(
name=get_bracketed_concat_expression(
*fields,
expression_to_bracket=bracketed_field,
),
)
assert queryset.first().name == expected_value
def test_get_top_related_expression_subquery(expression):
"""
Test that get_top_related_expression_subquery() can be used to get the name of the most
recently published book.
"""
person = PersonFactory()
book_data = [
{
'name': 'oldest',
'published_on': date(2010, 1, 1)
},
{
'name': 'in the middle',
'published_on': date(2013, 1, 1)
},
{
'name': 'newest',
'published_on': date(2015, 1, 1)
},
]
shuffle(book_data)
for item_data in book_data:
BookFactory(
proofreader=person,
authors=[],
**item_data,
)
queryset = Person.objects.annotate(
name_of_latest_book=get_top_related_expression_subquery(
Book.proofreader.field,
expression,
('-published_on', ),
), )
assert queryset.first().name_of_latest_book == 'newest'
def test_full_name_annotation(self):
"""Tests that a Person query set can be annotated with full names."""
person = PersonFactory()
queryset = Person.objects.annotate(name=get_full_name_expression(), )
expected_name = f'{person.first_name} {person.last_name}'
assert queryset.first().name == expected_name
def test_only_excludes_referenced_objects(self):
"""Test that only referenced objects are excluded."""
unreferenced_person = PersonFactory()
BookFactory()
queryset = get_unreferenced_objects_query(Person)
assert list(queryset) == [unreferenced_person]
def test_loading(self, migration_apps):
"""
Test that loading a yaml file updates the existing data.
"""
yaml_content = """
# person with pk=1, last_name should change
- model: datahub.core.test.support.person
pk: 1
fields:
first_name: Existing
last_name: Person with changed surname
# person with pk=3, first_name should change, last_name shouldn't change
- model: datahub.core.test.support.person
pk: 3
fields:
first_name: Another existing
# person with pk=10, a new record should be created
- model: datahub.core.test.support.person
pk: 10
fields:
first_name: New
last_name: Person
# book with pk=1, fk to person (proofreader) should change
- model: datahub.core.test.support.book
pk: 1
fields:
name: Book name
proofreader: 3
published_on: '2010-01-01'
"""
mocked_read = mock.mock_open(read_data=yaml_content)
people = PersonFactory.create_batch(
3,
pk=factory.Iterator([1, 2, 3]),
first_name='Existing',
last_name='Person',
)
BookFactory(
pk=1,
name='Previous book name',
proofreader=people[0],
published_on=datetime.date(2010, 1, 1),
authors=[],
)
with mock.patch('datahub.core.migration_utils.open', mocked_read, create=True):
load_yaml_data_in_migration(migration_apps, 'path-to-file.yaml')
qs = Person.objects.order_by('id').values('id', 'first_name', 'last_name')
assert list(qs) == [
{'id': 1, 'first_name': 'Existing', 'last_name': 'Person with changed surname'},
{'id': 2, 'first_name': 'Existing', 'last_name': 'Person'},
{'id': 3, 'first_name': 'Another existing', 'last_name': 'Person'},
{'id': 10, 'first_name': 'New', 'last_name': 'Person'},
]
qs = Book.objects.order_by('id').values('id', 'name', 'proofreader', 'published_on')
assert list(qs) == [
{
'id': 1,
'name': 'Book name',
'proofreader': 3,
'published_on': datetime.date(2010, 1, 1),
},
]