Type Module

The fundamental Ontic base data types for creation of derived child classes.

_images/ontic_type.jpg

Usage

Create Ontic Types

The ontic_type module provides the OnticType and a set of functions to handle the creation and validation of OnticType instances.

Construction of Ontic data types as a class definition:

>>> class MyType(OnticType):
...     ONTIC_SCHEMA = Schema({
...         'some_property': {
...             'type': 'int',
...             'required': True,
...         },
...         'other_property': {
...             'type': 'str',
...             'required': False,
...             'enum': {'Enum1', 'Enum2', 'Enum3'}
...         },
...     })
>>> my_object = MyType()
>>> my_object.some_property = 7
>>> # or
>>> my_object['some_property'] = 7
>>> validate_object(my_object)
[]

Dynamic Ontic Type Definition

It is also possible to create OnticType derived types dynamically with the use of the create_ontic_type() function.

>>> some_type = create_ontic_type('SomeType', {'prop':{'type':'int'}})
>>> my_object = some_type(prop=3)
>>> my_object
{'prop': 3}
>>> my_object.prop
3

Classes

OnticType

class ontic.OnticType(*args, **kwargs)

OnticType provides the Ontic schema interface.

The OnticType provides the schema management functionality to a derived Ontic type instance.

perfect() → NoReturn

Function to ensure complete attribute settings for a given object.

Perfecting an object instance will strip out any properties not defined in the corresponding object type. If there are any missing properties in the object, those properties will be added and set to the default value or None, if no default has been set.

For the collection types (dict, list, set), the default values are deep copied.

Return type

None

validate(raise_validation_exception: bool = True)

Validate the given OnticType instance against it’s defined schema.

Parameters

raise_validation_exception – If True, then validate_object will throw a ValueException upon validation failure. If False, then a list of validation errors is returned. Defaults to True.

Returns

If no validation errors are found, then None is returned. If validation fails, then a list of the errors is returned if the raise_validation_exception is set to True.

validate_value(value_name: str, raise_validation_exception: bool = True)

Validate a target value of a given ontic object.

Parameters

  • value_name – The value name to validate.

  • raise_validation_exception – If True, then validate_object will throw a ValueException upon validation failure. If False, then a list of validation errors is returned. Defaults to True.

Returns

If no validation errors are found, then None is returned. If validation fails, then a list of the errors is returned if the raise_validation_exception is set to True.

Functions

create_ontic_type

ontic.type.create_ontic_type(name: str, schema: (<class 'dict'>, <class 'ontic.schema.Schema'>)) → ontic.type.OnticType

Create an Ontic type to generate objects with a given schema.

create_ontic_type function creates an OnticType with a given name and schema definition. The schema definition can be a dict instance that is a valid schema definition or a ontic.schema_type.SchemaType. This makes the following forms valid:

MyType = create_ontic_type('MyType', {'prop':{'type':'int'}})

schema_instance = Schema(prop={'type':'int'})
MyType = create_ontic_type('MyType', schema_instance)
Parameters

  • name – The name to apply to the created class, with OnticType as parent.

  • schema – A representation of the schema in dictionary format.

Returns

A class whose base is OnticType.

Raises

ValueError – String name required. Dict or ontic.Schema schema required.

perfect_object

ontic.type.perfect_object(the_object: ontic.type.OnticType) → NoReturn

Function to ensure complete attribute settings for a given object.

Perfecting an object instance will strip out any properties not defined in the corresponding object type. If there are any missing properties in the object, those properties will be added and set to the default value or None, if no default has been set.

For the collection types (dict, list, set), the default values are deep copied.

Parameters

the_object – Ab object instance that is to be perfected.

validate_object

ontic.type.validate_object(the_object: ontic.type.OnticType, raise_validation_exception: bool = True)

Function that will validate if an object meets the schema requirements.

Parameters

  • the_object (OnticType) – An object instant to be validity tested.

  • raise_validation_exception – If True, then validate_object will throw a ValueException upon validation failure. If False, then a list of validation errors is returned. Defaults to True.

Returns

If no validation errors are found, then None is returned. If validation fails, then a list of the errors is returned if the raise_validation_exception is set to True.

Raises

  • ValueError – If the_object is None or not of type OnticType.

  • ValidationException – A property of the_object does not meet schema requirements.

validate_value

ontic.type.validate_value(property_name: str, ontic_object: ontic.type.OnticType, raise_validation_exception: bool = False)

Validate a specific value of a given OnticType instance.

Parameters

  • property_name – The value to be validated against the given PropertyType.

  • ontic_object – Ontic defined object to be validated.

  • raise_validation_exception – If True, then validate_object will throw a ValueException upon validation failure. If False, then a list of validation errors is returned. Defaults to True.

Returns

If no validation errors are found, then None is returned. If validation fails, then a list of the errors is returned if the raise_validation_exception is set to True.

Raises

  • ValueError – If property_name is not provided or is not a valid string.

  • ValueError – If ontic_object is None, or not instance of OnticType.

  • ValidationException – If the validation is not successful. The ValidationException will not be raised if raise_validation_exception is set to False.