def sort_query(self, query, sort_info):
"""Sort query according to jsonapi 1.0
:param Query query: sqlalchemy query to sort
:param list sort_info: sort information
:return Query: the sorted query
"""
for sort_opt in sort_info:
field = sort_opt['field']
if sort_opt.get('relationship'):
current_schema = self.resource.schema
for obj in sort_opt['relationship'].split('.'):
current_schema = get_related_schema(current_schema, obj)
if not hasattr(current_schema.Meta, 'model'):
raise InvalidSort("In order to sort on a relationship, meta model must be defined")
relationship_model = current_schema.Meta.model
query = query.join(relationship_model)
relationship_model = current_schema.Meta.model
model_field = get_model_field(current_schema, sort_opt['field'])
query = query.order_by(getattr(getattr(relationship_model, model_field), sort_opt['order'])())
elif not hasattr(self.model, field):
raise InvalidSort("{} has no attribute {}".format(self.model.__name__, field))
else:
query = query.order_by(getattr(getattr(self.model, field), sort_opt['order'])())
return query
def eagerload_includes(self, query, qs):
"""Use eagerload feature of sqlalchemy to optimize data retrieval for include querystring parameter
:param Query query: sqlalchemy queryset
:param QueryStringManager qs: a querystring manager to retrieve information from url
:return Query: the query with includes eagerloaded
"""
for include in qs.include:
joinload_object = None
if '.' in include:
current_schema = self.resource.schema
for obj in include.split('.'):
try:
field = get_model_field(current_schema, obj)
except Exception as e:
raise InvalidInclude(str(e))
if joinload_object is None:
joinload_object = joinedload(field, innerjoin=True)
else:
joinload_object = joinload_object.joinedload(
field, innerjoin=True)
related_schema_cls = get_related_schema(
current_schema, obj)
if isinstance(related_schema_cls, SchemaABC):
related_schema_cls = related_schema_cls.__class__
else:
related_schema_cls = class_registry.get_class(
related_schema_cls)
current_schema = related_schema_cls
else:
try:
field = get_model_field(self.resource.schema, include)
except Exception as e:
raise InvalidInclude(str(e))
joinload_object = joinedload(field, innerjoin=True)
query = query.options(joinload_object)
return query
