5.6 KiB
models.model
Model Objects
class Model(ModelRow)
upsert
| async upsert(**kwargs: Any) -> "Model"
Performs either a save or an update depending on the presence of the pk. If the pk field is filled it's an update, otherwise the save is performed. For save kwargs are ignored, used only in update if provided.
Arguments:
kwargs (Any): list of fields to update
Returns:
(Model): saved Model
save
| async save() -> "Model"
Performs a save of given Model instance. If primary key is already saved, db backend will throw integrity error.
Related models are saved by pk number, reverse relation and many to many fields are not saved - use corresponding relations methods.
If there are fields with server_default set and those fields are not already filled save will trigger also a second query to refreshed the fields populated server side.
Does not recognize if model was previously saved. If you want to perform update or insert depending on the pk fields presence use upsert.
Sends pre_save and post_save signals.
Sets model save status to True.
Returns:
(Model): saved Model
save_related
| async save_related(follow: bool = False, visited: Set = None, update_count: int = 0) -> int
Triggers a upsert method on all related models if the instances are not already saved. By default saves only the directly related ones.
If follow=True is set it saves also related models of related models.
To not get stuck in an infinite loop as related models also keep a relation to parent model visited models set is kept.
That way already visited models that are nested are saved, but the save do not follow them inside. So Model A -> Model B -> Model A -> Model C will save second Model A but will never follow into Model C. Nested relations of those kind need to be persisted manually.
Arguments:
follow (bool): flag to trigger deep save - by default only directly related models are saved with follow=True also related models of related models are savedvisited (Set): internal parameter for recursive calls - already visited modelsupdate_count (int): internal parameter for recursive calls - number of updated instances
Returns:
(int): number of updated/saved models
_update_and_follow
| @staticmethod
| async _update_and_follow(rel: "Model", follow: bool, visited: Set, update_count: int) -> Tuple[int, Set]
Internal method used in save_related to follow related models and update numbers of updated related instances.
Arguments:
rel (Model): Model to followfollow (bool): flag to trigger deep save - by default only directly related models are saved with follow=True also related models of related models are savedvisited (Set): internal parameter for recursive calls - already visited modelsupdate_count (int): internal parameter for recursive calls - number of updated instances
Returns:
(Tuple[int, Set]): tuple of update count and visited
update
| async update(**kwargs: Any) -> "Model"
Performs update of Model instance in the database. Fields can be updated before or you can pass them as kwargs.
Sends pre_update and post_update signals.
Sets model save status to True.
Raises:
ModelPersistenceError: If the pk column is not set
Arguments:
kwargs (Any): list of fields to update as field=value pairs
Returns:
(Model): updated Model
delete
| async delete() -> int
Removes the Model instance from the database.
Sends pre_delete and post_delete signals.
Sets model save status to False.
Note it does not delete the Model itself (python object). So you can delete and later save (since pk is deleted no conflict will arise) or update and the Model will be saved in database again.
Returns:
(int): number of deleted rows (for some backends)
load
| async load() -> "Model"
Allow to refresh existing Models fields from database. Be careful as the related models can be overwritten by pk_only models in load. Does NOT refresh the related models fields if they were loaded before.
Raises:
NoMatch: If given pk is not found in database.
Returns:
(Model): reloaded Model
load_all
| async load_all(follow: bool = False, exclude: Union[List, str, Set, Dict] = None) -> "Model"
Allow to refresh existing Models fields from database. Performs refresh of the related models fields.
By default loads only self and the directly related ones.
If follow=True is set it loads also related models of related models.
To not get stuck in an infinite loop as related models also keep a relation to parent model visited models set is kept.
That way already visited models that are nested are loaded, but the load do not follow them inside. So Model A -> Model B -> Model C -> Model A -> Model X will load second Model A but will never follow into Model X. Nested relations of those kind need to be loaded manually.
Raises:
NoMatch: If given pk is not found in database.
Arguments:
exclude ():follow (bool): flag to trigger deep save - by default only directly related models are saved with follow=True also related models of related models are saved
Returns:
(Model): reloaded Model