[rtags] Allow to 'derive' rtags
Since some releases, rtags (structure underlying uicfg) have selector and may be
copied using something like:
new_rtags = deepcopy(original_rtags)
new_rtags.__module__ = __name__
new_rtags.__select__ = custom_selector
The problem is that starting from that, both rtags wil diverge and changes in
original_rtags won't be considered, while we usually want to set a few specific
rules only in new_rtags. To fix this problem, this cset introduces the notion of
"derivated/parent" rtag, eg:
new_rtags = original_rtags.derive(__name__, custom_selector)
Beside easier copying, when using the above method changes in original_rtags
which are not overriden by new_rtags will be considered since it only hold its
specific rules but look among its parent chain for non-found keys.
Along the way, flake8 unittest_rtags.
Closes #16164880
"""Contains resources classes.
"""
from six import text_type
from rql import TypeResolverException
from pyramid.decorator import reify
from pyramid.httpexceptions import HTTPNotFound
class EntityResource(object):
"""A resource class for an entity. It provide method to retrieve an entity
by eid.
"""
@classmethod
def from_eid(cls):
def factory(request):
return cls(request, None, None, request.matchdict['eid'])
return factory
def __init__(self, request, cls, attrname, value):
self.request = request
self.cls = cls
self.attrname = attrname
self.value = value
@reify
def rset(self):
req = self.request.cw_request
if self.cls is None:
return req.execute('Any X WHERE X eid %(x)s',
{'x': int(self.value)})
st = self.cls.fetch_rqlst(self.request.cw_cnx.user, ordermethod=None)
st.add_constant_restriction(st.get_variable('X'), self.attrname,
'x', 'Substitute')
if self.attrname == 'eid':
try:
rset = req.execute(st.as_string(), {'x': int(self.value)})
except (ValueError, TypeResolverException):
# conflicting eid/type
raise HTTPNotFound()
else:
rset = req.execute(st.as_string(), {'x': text_type(self.value)})
return rset
class ETypeResource(object):
"""A resource for etype.
"""
@classmethod
def from_match(cls, matchname):
def factory(request):
return cls(request, request.matchdict[matchname])
return factory
def __init__(self, request, etype):
vreg = request.registry['cubicweb.registry']
self.request = request
self.etype = vreg.case_insensitive_etypes[etype.lower()]
self.cls = vreg['etypes'].etype_class(self.etype)
def __getitem__(self, value):
# Try eid first, then rest attribute as for URL path evaluation
# mecanism in cubicweb.web.views.urlpublishing.
for attrname in ('eid', self.cls.cw_rest_attr_info()[0]):
resource = EntityResource(self.request, self.cls, attrname, value)
try:
rset = resource.rset
except HTTPNotFound:
continue
if rset.rowcount:
return resource
raise KeyError(value)
@reify
def rset(self):
rql = self.cls.fetch_rql(self.request.cw_cnx.user)
rset = self.request.cw_request.execute(rql)
return rset