def get_foreign_key_ref(
foreign_value: QueryExpression,
reference_collection_name: QueryExpression,
) -> QueryExpression:
"""Get the Ref to a document associated with a foreign key value.
Params:
-------
foreign_value: The value to look up, usually an ID.
references: Field metadata dict that defines the collection (key) and field name (value)
that the foreign key refers to.
Returns:
--------
Fauna query expression that returns an array of Refs for the associated document(s).
"""
return q.let(
{
"is_blank_reference":
q.or_(
q.is_null(foreign_value),
q.equals(foreign_value, NULL),
q.equals(reference_collection_name, NULL),
),
},
q.if_(
q.var("is_blank_reference"),
None,
q.ref(q.collection(reference_collection_name), foreign_value),
),
)
def test_or_expr(self):
self.assertJson(query.or_(False), '{"or":false}')
self.assertJson(query.or_(False, True, True),
'{"or":[false,true,true]}')
self.assertJson(query.or_([False, True, True]),
'{"or":[false,true,true]}')
def test_or(self):
self.assertTrue(self._q(query.or_(False, False, True)))
self.assertFalse(self._q(query.or_(False, False, False)))
self.assertTrue(self._q(query.or_(True)))
self.assertFalse(self._q(query.or_(False)))
self._assert_bad_query(query.or_())