def _key_to_id(self, key):
"""
Fragments should be permitted to have any desired external_ref -- which means key_to_id needs to store a
mapping of non-standard external refs to uuids. This is only because (at the moment) every entity is stored
in the archive using a uuid as its internal key.
Open question: should this be a general feature? currently only NsUuidArchives allow arbitrary external_refs.
Answer: no. uuids are still king (for now)
This function is a little different from other EntityStore subclasses because it (uniquely) needs to handle
entities from a variety of origins. Therefore we use the link and not the uuid as an identifer. However, we
still need to support retrieval by UUID. **WE WANT TO DO THIS WITHOUT HAVING TO OVERRIDE __getitem__**.
So the operation is as follows:
* _key_to_id transmits the user's heterogeneous input into a valid key to self._entities, or None
- if the key is already a known link, it's easy
- if the key is a custom name, it's almost as easy
- if the key CONTAINS a uuid known to the db, then a link for an entity with that UUID is
NONDETERMINISTICALLY returned
* __getitem__ uses _key_to_id to translate the users input into a key
For the thorns around renaming fragments, see self.name_fragment() below
:param key:
:return:
"""
if key in self._entities:
return key
elif key in self._ext_ref_mapping:
return self._ext_ref_mapping[key]
else:
uid = to_uuid(key)
if uid in self._uuid_map:
return next(k for k in self._uuid_map[uid])
return None
def __init__(self, ref, ns_uuid=None, **kwargs):
super(NsUuidArchive, self).__init__(ref, **kwargs)
# internal namespace UUID for generating keys
if ns_uuid is None:
if self._upstream is not None:
if isinstance(self._upstream, NsUuidArchive):
ns_uuid = self._upstream._ns_uuid
ns_uuid = to_uuid(ns_uuid) # if it's already a uuid, keep it; if it's a string, find it; else None
self._ns_uuid = uuid.uuid4() if ns_uuid is None else ns_uuid
self._serialize_dict['nsUuid'] = str(self._ns_uuid)
def _key_to_id(self, key):
"""
Converts Ecospold01 "number" attributes to UUIDs using the internal UUID namespace.
:param key:
:return:
"""
if isinstance(key, int):
key = str(key)
u = to_uuid(key)
if u is not None:
return u
if six.PY2:
return uuid.uuid3(self._ns_uuid, key.encode('utf-8'))
else:
return uuid.uuid3(self._ns_uuid, key)
def get_entity_uuid(item):
if to_uuid(item) is not None:
return item
if hasattr(item, "get_uuid"):
return item.get_uuid()
raise TypeError("Don't know how to get ID from %s" % type(item))
def get_entity_uuid(item):
if to_uuid(item) is not None:
return item
if hasattr(item, 'get_uuid'):
return item.get_uuid()
raise TypeError('Don\'t know how to get ID from %s' % type(item))
