oldman.management package

oldman.management.ancestry module

class oldman.management.ancestry.ClassAncestry(child_class_iri, schema_graph)

Bases: object

Ancestry of a given RDFS class.

Parameters:

• child_class_iri – IRI of the child RDFS class.
• schema_graph – rdflib.Graph object contains all the schema triples.

bottom_up

Ancestry list starting from the child.

child

Child of the ancestry.

parents(class_iri)

Finds the parents of a given class in the ancestry.

Parameters:class_iri – IRI of the RDFS class. Returns:List of class IRIs

top_down

Reverse of the bottom_up attribute.

oldman.management.manager module

class oldman.management.manager.ResourceManager(schema_graph, data_store, attr_extractor=None, manager_name='default')

Bases: object

The resource_manager is the central object of this OLDM.

It gives access to the DataStore object and creates Model objects. It also creates, retrieves and caches Resource objects.

Internally, it owns a ModelRegistry object.

Parameters:

• schema_graph – rdflib.Graph object containing all the schema triples.
• data_store – DataStore object. Supports CRUD operations on Resource objects.
• attr_extractor – OMAttributeExtractor object that will extract OMAttribute for generating new Model objects. Defaults to a new instance of OMAttributeExtractor.
• manager_name – Name of this manager. Defaults to “default”. This name must be unique.

create(id=None, types=None, hashless_iri=None, **kwargs)

Creates a new resource and save it in the data_store.

See new() for more details.

create_model(class_name_or_iri, context, iri_generator=None, iri_prefix=None, iri_fragment=None, incremental_iri=False)

Creates a Model object.

To create it, they are three elements to consider:

1. Its class IRI which can be retrieved from class_name_or_iri;
2. Its JSON-LD context for mapping OMAttribute values to RDF triples;
3. The IriGenerator object that generates IRIs from new Resource objects.

The IriGenerator object is either:

• directly given: iri_generator;
• created from the parameters iri_prefix, iri_fragment and incremental_iri.

Parameters:

• class_name_or_iri – IRI or JSON-LD term of a RDFS class.
• context – dict, list or IRI that represents the JSON-LD context .
• iri_generator – IriGenerator object. If given, other iri_* parameters are ignored.
• iri_prefix – Prefix of generated IRIs. Defaults to None. If is None and no iri_generator is given, a BlankNodeIriGenerator is created.
• iri_fragment – IRI fragment that is added at the end of generated IRIs. For instance, “me” adds “#me” at the end of the new IRI. Defaults to None. Has no effect if iri_prefix is not given.
• incremental_iri – If True an IncrementalIriGenerator is created instead of a RandomPrefixedIriGenerator. Defaults to False. Has no effect if iri_prefix is not given.

Returns:

A new Model object.

data_store

DataStore object. Supports CRUD operations on :class:`~oldman.resource.Resource objects`.

declare_method(method, name, class_iri)

Attaches a method to the Resource objects that are instances of a given RDFS class.

Like in Object-Oriented Programming, this method can be overwritten by attaching a homonymous method to a class that has a higher inheritance priority (such as a sub-class).

To benefit from this method (or an overwritten one), Resource objects must be associated to a Model that corresponds to the RDFS class or to one of its subclasses.

This method can only be used before the creation of any model (except the default one).

Parameters:

• method – Python function that takes as first argument a Resource object.
• name – Name assigned to this method.
• class_iri – Targetted RDFS class. If not overwritten, all the instances (Resource objects) should inherit this method.

filter(types=None, hashless_iri=None, limit=None, eager=False, pre_cache_properties=None, **kwargs)

See oldman.store.datastore.DataStore.filter().

find_models_and_types(type_set)

See oldman.management.registry.ModelRegistry.find_models_and_types().

get(id=None, types=None, hashless_iri=None, eager_with_reversed_attributes=True, **kwargs)

See oldman.store.datastore.DataStore.get().

classmethod get_manager(name)

Gets a ResourceManager object by its name.

Parameters:name – manager name. Returns:A ResourceManager object.

include_reversed_attributes

Is True if at least one of its models use some reversed attributes.

name

Name of this manager. The manager can be retrieved from its name by calling the class method get_manager().

new(id=None, types=None, hashless_iri=None, **kwargs)

Creates a new Resource object without saving it in the data_store.

The kwargs dict can contains regular attribute key-values that will be assigned to OMAttribute objects.

Parameters:

• id – IRI of the new resource. Defaults to None. If not given, the IRI is generated by the IRI generator of the main model.
• types – IRIs of RDFS classes the resource is instance of. Defaults to None. Note that these IRIs are used to find the models of the resource (see find_models_and_types() for more details).
• hashless_iri – hash-less IRI that MAY be considered when generating an IRI for the new resource. Defaults to None. Ignored if id is given.

Returns:

A new Resource object.

sparql_filter(query)

See oldman.store.datastore.DataStore.sparql_filter().

oldman.management.registry module

class oldman.management.registry.ModelRegistry

Bases: object

A ModelRegistry object registers the Model objects.

Its main function is to find and order models from a set of class IRIs (this ordering is crucial when creating new Resource objects). See find_models_and_types() for more details.

find_models_and_types(type_set)

Finds the leaf models from a set of class IRIs and orders them. Also returns an ordered list of the RDFS class IRIs that come from type_set or were deduced from it.

Leaf model ordering is important because it determines:

1. the IRI generator to use (the one of the first model);
2. method inheritance priorities between leaf models.

Resulting orderings are cached.

Parameters:type_set – Set of RDFS class IRIs. Returns:An ordered list of leaf Model objects and an ordered list of RDFS class IRIs.

get_model(class_iri)

Gets a Model object.

Parameters:class_iri – IRI of a RDFS class Returns:A Model object or None if not found

has_specific_models()

Returns:True if contains other models than the default one.

model_names

Names of the registered models.

register(model, is_default=False)

Registers a Model object.

Parameters:

• model – the Model object to register.
• is_default – If True, sets the model as the default model. Defaults to False.

unregister(model)

Un-registers a Model object.

Parameters:model – the Model object to remove from the registry.