flask_more_smorest.sqla.base_model

Base model for SQLAlchemy models with automatic schema generation.

This module provides BaseModel, a base class for all SQLAlchemy models that includes automatic Marshmallow schema generation and common CRUD operations.

Classes

`BaseModel`(**kwargs)	Base model for all application models.
`BaseModelMeta`(name, bases, attrs)	Metaclass for BaseModel that provides automatic schema generation.

class flask_more_smorest.sqla.base_model.BaseModelMeta(name, bases, attrs)[source]

Metaclass for BaseModel that provides automatic schema generation.

This metaclass automatically generates a Marshmallow schema for each model class, with proper configuration for relationships, foreign keys, and dump-only fields.

__getattr__(name)[source]

Get attribute with lazy schema generation.

Parameters:: name (str) – Attribute name to retrieve
Return type:: Any
Returns:: The schema class if name is ‘Schema’, otherwise raises AttributeError
Raises:: AttributeError – If the attribute doesn’t exist

__init__(name, bases, attrs)[source]

Initialize the metaclass.

Parameters:

name (str) – Name of the class being created
bases (tuple[type, ...]) – Tuple of base classes
attrs (dict[str, object]) – Dictionary of class attributes

class flask_more_smorest.sqla.base_model.BaseModel(**kwargs)[source]

Base model for all application models.

This base class provides: - Automatic UUID primary key generation - Automatic created_at and updated_at timestamps - Automatic Marshmallow schema generation via Model.Schema - Common CRUD operations (get, save, update, delete) - Lifecycle hooks (on_before_create, on_after_create, etc.)

All models should inherit from this class to get these features.

id: UUID primary key (automatically generated)

created_at: Timestamp of creation

updated_at: Timestamp of last update

Schema: Auto-generated Marshmallow schema class

Example

>>> class Article(BaseModel):
...     title: Mapped[str] = mapped_column(sa.String(200))
...     content: Mapped[str] = mapped_column(sa.Text)
...
>>> # Use auto-generated schema
>>> article_bp = CRUDBlueprint(
...     'articles', __name__,
...     model=Article,
...     schema=Article.Schema  # No need to define custom schema
... )

id: Mapped[UUID] = <sqlalchemy.orm.properties.MappedColumn object>

created_at: Mapped[datetime] = <sqlalchemy.orm.properties.MappedColumn object>

updated_at: Mapped[datetime] = <sqlalchemy.orm.properties.MappedColumn object>

__init__(**kwargs)[source]

Initialize the model.

Parameters:: **kwargs (object) – Field values to initialize the model with
Raises:: RuntimeError – If database session is not active

property is_writable: bool

Return whether the instance is writable.

BaseModel does not enforce permissions, so instances are considered writable by default. Permission-aware subclasses can override this property.

classmethod get_by(**kwargs)[source]

Get resource by field values.

Converts UUID strings to UUID objects automatically for UUID columns.

Parameters:: **kwargs (str | int | UUID | bool | None) – Field name and value pairs to filter by
Return type:: Optional[Self]
Returns:: The matching model instance, or None if not found
Raises:: TypeError – If ID is not a valid UUID string or UUID object

Example

>>> user = User.get_by(email='test@example.com')
>>> article = Article.get_by(id='123e4567-e89b-12d3-a456-426614174000')

classmethod get_by_or_404(**kwargs)[source]

Get resource by field values or raise 404.

Parameters:

**kwargs (str | int | UUID | bool | None) – Field name and value pairs to filter by

Return type:

Self

Returns:

The matching model instance

Raises:

NotFoundError – If no matching resource is found
TypeError – If ID field has invalid UUID format
ForbiddenError – If user doesn’t have read permission

Example

>>> user = User.get_by_or_404(email='test@example.com')

classmethod get(id)[source]

Get resource by ID.

Parameters:: id (UUID | str) – Resource ID (UUID or UUID string)
Return type:: Optional[Self]
Returns:: The matching model instance, or None if not found

Example

>>> user = User.get('123e4567-e89b-12d3-a456-426614174000')

classmethod get_or_404(id)[source]

Get resource by ID or raise 404.

Parameters:: id (UUID | str) – Resource ID (UUID or UUID string)
Return type:: Self
Returns:: The matching model instance
Raises:: NotFoundError – If no matching resource is found

Example

>>> user = User.get_or_404('123e4567-e89b-12d3-a456-426614174000')

classmethod check_exists(id)[source]

Check if resource exists and throw 404 otherwise.

Parameters:: id (UUID | str) – Resource ID to check
Raises:: NotFoundError – If resource doesn’t exist
Return type:: None

classmethod bypass_perms(cls)[source]

No-op context manager for base class (overridden in perms model).

Return type:: Iterator[None]

save(commit=True)[source]

Save the record: add to session and optionally commit.

Parameters:: commit (bool) – Whether to commit the transaction (default: True)
Return type:: Self
Returns:: The saved model instance (self)
Raises:: ForbiddenError – If user doesn’t have permission to create/modify

Example

>>> user = User(email='test@example.com')
>>> user.save()

commit(is_delete=False, *, is_create=None)[source]

Commit the session and call appropriate lifecycle hooks.

Parameters:

is_delete (bool) – Whether this is a delete operation (default: False)
is_create (bool | None) – Explicit flag indicating whether this commit corresponds to a creation

Return type:

None

update(commit=True, **kwargs)[source]

Update model fields using key-value pairs.

Supports updating relationships and recursively checks create permissions for nested objects.

Parameters:

commit (bool) – Whether to commit the transaction (default: True)
**kwargs (str | int | float | bool | bytes | None) – Field names and values to update

Raises:

AttributeError – If field doesn’t exist on the model
ForbiddenError – If user doesn’t have permission to modify

Return type:

None

Example

>>> user.update(email='new@example.com', is_active=False)

delete(commit=True)[source]

Delete the record from the database.

Parameters:: commit (bool) – Whether to commit the transaction (default: True)
Raises:: ForbiddenError – If user doesn’t have permission to delete
Return type:: None

Example

>>> user = User.get(user_id)
>>> user.delete()

get_clone()[source]

Return a copy of the object with a new ID.

Creates a detached copy of this instance with ID set to None, suitable for creating a duplicate record.

Return type:: Self
Returns:: A new instance with the same field values but no ID

Example

>>> original = User.get(user_id)
>>> clone = original.get_clone()
>>> clone.save()  # Creates new record

on_before_create()[source]

Hook to be called before creating the object.

Override this method to add custom logic before object creation.

Return type:: None

on_after_create()[source]

Hook to be called after creating the object.

Override this method to add custom logic after object creation.

Return type:: None

on_before_update()[source]

Hook to be called before updating the object.

Override this method to add custom logic before object updates.

Return type:: None

on_after_update()[source]

Hook to be called after updating the object.

Override this method to add custom logic after object updates.

Return type:: None

on_before_delete()[source]

Hook to be called before deleting the object.

Override this method to add custom logic before object deletion.

Return type:: None

on_after_delete()[source]

Hook to be called after deleting the object.

Override this method to add custom logic after object deletion.

Return type:: None

check_create(val)[source]

Recursively validate nested models before creating them.

Ensures nested BaseModel instances have an opportunity to perform their own permission checks (for example, BasePermsModel subclasses).

Return type:: None

__repr__()[source]

Return string representation of the model.

Return type:: str
Returns:: String in format “<ModelName id=…>”