def resolve_json_id(self, json_id, allow_no_match=False):
"""
Given an id found in scraped JSON, return a DB id for the object.
params:
json_id: id from json
allow_no_match: just return None if id can't be resolved
returns:
database id
raises:
ValueError if id couldn't be resolved
"""
if not json_id:
return None
if json_id.startswith('~'):
# keep caches of all the pseudo-ids to avoid doing 1000s of lookups during import
if json_id not in self.pseudo_id_cache:
spec = get_pseudo_id(json_id)
spec = self.limit_spec(spec)
if isinstance(spec, Q):
objects = self.model_class.objects.filter(spec)
else:
objects = self.model_class.objects.filter(**spec)
ids = {each.id for each in objects}
if len(ids) == 1:
self.pseudo_id_cache[json_id] = ids.pop()
errmsg = None
elif not ids:
errmsg = 'cannot resolve pseudo id to {}: {}'.format(
self.model_class.__name__, json_id)
else:
errmsg = 'multiple objects returned for {} pseudo id {}: {}'.format(
self.model_class.__name__, json_id, ids)
# either raise or log error
if errmsg:
if not allow_no_match:
raise UnresolvedIdError(errmsg)
else:
self.error(errmsg)
self.pseudo_id_cache[json_id] = None
# return the cached object
return self.pseudo_id_cache[json_id]
# get the id that the duplicate points to, or use self
json_id = self.duplicates.get(json_id, json_id)
try:
return self.json_to_db_id[json_id]
except KeyError:
raise UnresolvedIdError('cannot resolve id: {}'.format(json_id))
def resolve_json_id(self, json_id):
"""
Given an id found in scraped JSON, return a DB id for the object.
params:
json_id: id from json
returns:
database id
raises:
ValueError if id couldn't be resolved
"""
if not json_id:
return None
if json_id.startswith('~'):
# keep caches of all the pseudo-ids to avoid doing 1000s of lookups during import
if json_id not in self.pseudo_id_cache:
spec = get_pseudo_id(json_id)
spec = self.limit_spec(spec)
try:
self.pseudo_id_cache[
json_id] = self.model_class.objects.get(**spec).id
except self.model_class.DoesNotExist:
raise UnresolvedIdError(
'cannot resolve pseudo id to {}: {}'.format(
self.model_class.__name__, json_id))
except self.model_class.MultipleObjectsReturned:
raise UnresolvedIdError(
'multiple objects returned for pseudo id to {}: {}'.
format(self.model_class.__name__, json_id))
# return the cached object
return self.pseudo_id_cache[json_id]
# get the id that the duplicate points to, or use self
json_id = self.duplicates.get(json_id, json_id)
try:
return self.json_to_db_id[json_id]
except KeyError:
raise UnresolvedIdError('cannot resolve id: {}'.format(json_id))