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Validators and managers

The building blocks behind the fields and models, usable on their own.

JSONSchemaValidator​

Validates a value against a JSON Schema. Used internally by FlexField.

from blueprint.validators import JSONSchemaValidator


validator = JSONSchemaValidator(json_schema={"type": "integer"})
validator(42)      # passes
validator("42")    # raises ValidationError

The validator is @deconstructible and implements equality on its schema, message and code — safe to use in fields that end up in migrations. The default message and code can be overridden:

validator = JSONSchemaValidator(
    json_schema={"type": "integer"},
    message="Enter a whole number.",
    code="whole_number",
)

ChoiceOptionsValidator​

Validates that every value in a list is one of the allowed options. Used internally by MultipleChoiceField.

from blueprint.validators import ChoiceOptionsValidator


validator = ChoiceOptionsValidator(options=[("a", "Alpha"), ("b", "Beta")])
validator(["a", "b"])   # passes
validator(["a", "x"])   # raises ValidationError

SingletonManager​

The manager behind SingletonModel. get() returns the first instance or None; create() creates or updates.

SoftDeletableManager and SoftDeletableQuerySet​

SoftDeletableManager filters out instances with a removed_at stamp — it is what available_objects is on every soft-deletable model. SoftDeletableQuerySet soft-deletes on delete(); see soft deletion.