jschon.catalog

class jschon.catalog.Catalog(name='catalog')

The Catalog acts as a schema cache, enabling schemas and subschemas to be indexed, re-used, and cross-referenced by URI.

Parameters

name (str) –

Return type

None

__init__(name='catalog')

Initialize a Catalog instance.

Parameters

name (str) – a unique name for this Catalog instance

Return type

None

add_schema(uri, schema, *, cacheid='default')

Add a (sub)schema to a cache.

Parameters
Return type

None

add_uri_source(base_uri, source)

Register a source for URI-identified JSON resources.

Parameters
Raises

CatalogError – if base_uri is invalid

cache(cacheid=None)

Context manager for a schema cache.

Example usage:

with catalog.cache() as cacheid:
    schema = JSONSchema(..., cacheid=cacheid)

The cache and its contents are popped from the catalog upon exiting the with block.

Parameters

cacheid (Hashable) –

Return type

AbstractContextManager[Hashable]

create_metaschema(uri, core_vocabulary_uri, *default_vocabulary_uris, **kwargs)

Create, cache and validate a Metaschema.

Parameters

  • uri (jschon.uri.URI) – the URI identifying the metaschema

  • core_vocabulary_uri (jschon.uri.URI) – the URI identifying the metaschema’s core Vocabulary

  • default_vocabulary_uris (jschon.uri.URI) – default Vocabulary URIs, used in the absence of a "$vocabulary" keyword in the metaschema JSON file

  • kwargs (Any) – additional keyword arguments to pass through to the JSONSchema constructor

Return type

None

create_vocabulary(uri, *kwclasses)

Create a Vocabulary object, which may be used by a Metaschema to provide keyword classes used in schema construction.

Parameters
Return type

None

del_schema(uri, *, cacheid='default')

Remove a (sub)schema from a cache.

Parameters

  • uri (jschon.uri.URI) – the URI identifying the (sub)schema

  • cacheid (Hashable) – schema cache identifier

Return type

None

enable_formats(*format_attr)

Enable validation of the specified format attributes.

These may include formats defined in jschon.formats and elsewhere.

Parameters

format_attr (str) –

Return type

None

classmethod get_catalog(name='catalog')
Parameters

name (str) –

Return type

jschon.catalog.Catalog

get_schema(uri, *, metaschema_uri=None, cacheid='default')

Get a (sub)schema identified by uri from a cache, or load it from disk if not already cached.

Parameters

  • uri (jschon.uri.URI) – the URI identifying the (sub)schema

  • metaschema_uri (Optional[jschon.uri.URI]) – passed to the JSONSchema constructor when loading a new instance from disk

  • cacheid (Hashable) – schema cache identifier

Raises

CatalogError – if a schema cannot be found for uri, or if the object referenced by uri is not a JSONSchema

Return type

jschon.jsonschema.JSONSchema

get_vocabulary(uri)

Get a Vocabulary by its uri.

Parameters

uri (jschon.uri.URI) – the URI identifying the vocabulary

Raises

CatalogError – if uri is not a recognized vocabulary URI

Return type

jschon.vocabulary.Vocabulary

is_format_enabled(format_attr)

Return True if validation is enabled for format_attr, False otherwise.

Return type

bool

load_json(uri)

Load a JSON-compatible object from the source for uri.

If there are multiple candidate base URIs for uri, the most specific match (i.e. the longest one) is selected.

Parameters

uri (jschon.uri.URI) – a normalized, absolute URI - including scheme, without a fragment

Raises

CatalogError – if uri is invalid, a source is not available for uri, or if a loading error occurs

Return type

Union[None, bool, int, float, str, Sequence[Any], Mapping[str, Any]]

name: str

The unique name of this Catalog instance.

class jschon.catalog.LocalSource(base_dir, **kwargs)
Parameters

  • base_dir (Union[str, PathLike]) –

  • kwargs (Any) –

Return type

None

__call__(relative_path)
Parameters

relative_path (str) –

Return type

Union[None, bool, int, float, str, Sequence[Any], Mapping[str, Any]]

__init__(base_dir, **kwargs)
Parameters

  • base_dir (Union[str, os.PathLike]) –

  • kwargs (Any) –

Return type

None

class jschon.catalog.RemoteSource(base_url, **kwargs)
Parameters

  • base_url (URI) –

  • kwargs (Any) –

Return type

None

__call__(relative_path)
Parameters

relative_path (str) –

Return type

Union[None, bool, int, float, str, Sequence[Any], Mapping[str, Any]]

__init__(base_url, **kwargs)
Parameters
Return type

None

class jschon.catalog.Source(suffix=None)
Parameters

suffix (str) –

Return type

None

__call__(relative_path)
Parameters

relative_path (str) –

Return type

Union[None, bool, int, float, str, Sequence[Any], Mapping[str, Any]]

__init__(suffix=None)
Parameters

suffix (Optional[str]) –

Return type

None