import re
from atramhasis.errors import ConceptSchemeNotFoundException
"""
Thid module is used when blocking operations on a certain Concept or Collection
that might be used in external applications.
:versionadded: 0.4.0
"""
[docs]class ProtectedResourceEvent:
"""
Event triggered when calling a protected operation on a resource
"""
def __init__(self, uri, request):
self.uri = uri
self.request = request
[docs]def protected_operation(fn):
"""
use this decorator to prevent an operation from being executed
when the related resource is still in use
"""
def advice(parent_object, *args, **kw):
request = parent_object.request
url = request.path
match = re.compile(r'/conceptschemes/(\w+)/c/(\w+)').match(url)
scheme_id = match.group(1)
c_id = match.group(2)
provider = request.skos_registry.get_provider(scheme_id)
if not provider:
raise ConceptSchemeNotFoundException(scheme_id)
uri = provider.uri_generator.generate(id=c_id)
event = ProtectedResourceEvent(uri, request)
parent_object.request.registry.notify(event)
return fn(parent_object, *args, **kw)
return advice
[docs]class ProtectedResourceException(Exception):
"""
raise this exception when the resource is still used somewhere
referenced_in should contain locations where the resource is still referenced
"""
def __init__(self, value, referenced_in):
self.value = value
self.referenced_in = referenced_in
def __str__(self):
return repr(self.value)