INTPYTHON-624 Add PolymorphicEmbeddedModelField #327
Conversation
| if transform: | ||
| return transform | ||
| field = None | ||
| for model in self.embedded_models: |
There was a problem hiding this comment.
what if multiple submodes has the same field name?
There was a problem hiding this comment.
I called this out in the design doc. I think we'll have to use the system check framework to enforce that common field names at least use the same type, otherwise, we won't know how to prepare the lookup value (e.g. the DatabaseOperations.adapt_<field>_value() methods).
Thinking about it some more, there is also the possibility that nested embedded documents share a field name. In that case, we won't know which field to traverse for the nested lookups that follow.
| @@ -121,8 +121,10 @@ def _isnull_operator(a, b): | |||
| "gte": lambda a, b: {"$gte": [a, b]}, | |||
| # MongoDB considers null less than zero. Exclude null values to match | |||
| # SQL behavior. | |||
| "lt": lambda a, b: {"$and": [{"$lt": [a, b]}, {"$ne": [a, None]}]}, | |||
| "lte": lambda a, b: {"$and": [{"$lte": [a, b]}, {"$ne": [a, None]}]}, | |||
| "lt": lambda a, b: {"$and": [{"$lt": [a, b]}, DatabaseWrapper._isnull_operator(a, False)]}, | |||
There was a problem hiding this comment.
This introduces a regression in model_fields_.test_embedded_model_array.QueryingTests.test_array_as_rhs_for_arrayfield_lookups) (lookup='lt'):
pymongo.errors.OperationFailure: Expression $type takes exactly 1 arguments. 2 were passed in., full error: {'ok': 0.0, 'errmsg': 'Expression $type takes exactly 1 arguments. 2 were passed in.', 'code': 16020, 'codeName': 'Location16020'}
Probably an array literal is treated as a multi-argument value in "$eq": [{"$type": a}, "missing"]},
There was a problem hiding this comment.
Yes, it seems, If I don't remember wrong, the Value(value) is transformed in {"$literal": value}. So the $eq should work. I have to debug this particular case.
There was a problem hiding this comment.
Well, the literal literally fixes the issue.
In django_mongodb_backend/expressions.py, make the following change:
--- a/django_mongodb_backend/expressions.py
+++ b/django_mongodb_backend/expressions.py
@@ def value(self, compiler, connection): # noqa: ARG001
value = self.value
- if isinstance(value, int):
- # Wrap numbers in $literal to prevent ambiguity when Value appears in
+ if isinstance(value, int | list):
+ # Wrap numbers and list in $literal to prevent ambiguity when Value appears in
# $project.
return {"$literal": value}
| ) | ||
| field_name = field.name | ||
| if existing_field := embedded_fields.get(field.name): | ||
| connection = _get_mongodb_connection() |
There was a problem hiding this comment.
This check should run anytime? or only when a migration is applied on the database? 🤔
Given that make migrations does not pass the database, because it should be agnostic to that but when a migration is applied it should not be agnostic. So when do we want to check this? when a migration is created, or anytime?
Edit: change the way that field types are compared is viable?
No description provided.