sqlalchemyseed.attribute

attribute module containing helper functions for instrumented attribute.

Module Contents

sqlalchemyseed.attribute.attr_is_column(instrumented_attr: sqlalchemy.orm.attributes.InstrumentedAttribute)

Check if instrumented attribute property is a ColumnProperty

sqlalchemyseed.attribute.attr_is_relationship(instrumented_attr: sqlalchemy.orm.attributes.InstrumentedAttribute)

Check if instrumented attribute property is a RelationshipProperty

sqlalchemyseed.attribute.check_scalar_cardinality(instance, attr_name, value, strict=False)

Guard against binding a list to a scalar relationship (gap #4).

A scalar relationship (uselist=False) given a list keeps only the last element via repeated assignment — silent data loss. When value is a list of more than one item, this raises if strict else warns. A single-element list is left alone (assigning one element is correct).

This guard only inspects the child value itself: it does not detect the equivalent last-wins case expressed as a nested data list (e.g. {"!company": {"data": [{...}, {...}]}}), which remains out of scope for gap #4.

sqlalchemyseed.attribute.foreign_key_column(instrumented_attr: sqlalchemy.orm.attributes.InstrumentedAttribute)

Returns the table name of the first foreignkey.

sqlalchemyseed.attribute.instrumented_attribute(class_or_instance, key: str)

Returns instrumented attribute from the class or instance.

sqlalchemyseed.attribute.referenced_class(instrumented_attr: sqlalchemy.orm.attributes.InstrumentedAttribute)

Returns class that the attribute is referenced to.

sqlalchemyseed.attribute.set_instance_attribute(instance, key, value)

Set attribute value of instance