"""
This module provides utilities for working with :term:`URIs <URI>`.
.. versionadded:: 0.3.0
"""
import abc
import rfc3987
[docs]
def is_uri(uri):
"""
Check if a string is a valid URI according to rfc3987
:param string uri:
:rtype: boolean
"""
if uri is None:
return False
return rfc3987.match(uri, rule="URI")
[docs]
class UriGenerator:
"""
An abstract class for generating URIs.
"""
__metaclass__ = abc.ABCMeta
[docs]
@abc.abstractmethod
def generate(self, **kwargs):
"""
Generate a :term:`URI` based on parameters passed.
"""
[docs]
class UriPatternGenerator(UriGenerator):
"""
Generate a :term:`URI` based on a simple pattern.
"""
def __init__(self, pattern):
self.pattern = pattern
[docs]
def generate(self, **kwargs):
"""
Generate a :term:`URI` based on parameters passed.
:param id: The id of the concept or collection.
:rtype: string
"""
return self.pattern % kwargs["id"]
[docs]
class DefaultUrnGenerator(UriGenerator):
"""
Generate a :term:`URN` specific to skosprovider.
Used for providers that do not implement a specific :class:`UriGenerator`.
:param vocabulary_id: An identifier for the vocabulary we're generating
URIs for.
"""
pattern = "urn:x-skosprovider:%s:%s"
def __init__(self, vocabulary_id):
self.vocabulary_id = vocabulary_id
[docs]
def generate(self, **kwargs):
"""
Generate a :term:`URI` based on parameters passed.
:param id: The id of the concept or collection.
:rtype: string
"""
return (self.pattern % (self.vocabulary_id, kwargs["id"])).lower()
[docs]
class DefaultConceptSchemeUrnGenerator(UriGenerator):
"""
Generate a :term:`URN` for a conceptscheme specific to skosprovider.
Used for generating default :term:`URIs <URI>` for providers that do
not have an explicit conceptscheme.
"""
pattern = "urn:x-skosprovider:%s"
[docs]
def generate(self, **kwargs):
"""
Generate a :term:`URI` based on parameters passed.
:param id: The id of the conceptscheme.
:rtype: string
"""
return (self.pattern % (kwargs["id"])).lower()
[docs]
class TypedUrnGenerator(DefaultUrnGenerator):
"""
Generate a :term:`URN` specific to skosprovider that contains a type.
:param vocabulary_id: An identifier for the vocabulary we're generating
URIs for.
"""
pattern = "urn:x-skosprovider:%s:%s:%s"
def __init__(self, vocabulary_id):
self.vocabulary_id = vocabulary_id
[docs]
def generate(self, **kwargs):
"""
Generate a :term:`URI` based on parameters passed.
:param id: The id of the concept or collection.
:param type: What we're generating a :term:`URI` for: `concept`
or `collection`.
:rtype: string
"""
if kwargs["type"] not in ["concept", "collection"]:
raise ValueError(f"Type {kwargs['type']} is invalid")
return (
self.pattern % (self.vocabulary_id, kwargs["type"], kwargs["id"])
).lower()