def create_functions(models_module, update=True):
"""Create the database functions for a given models module.
"""
for name, function_cls in vars(models_module).iteritems():
is_function = (
isinstance(function_cls, type) and
issubclass(function_cls, Function) and
hasattr(function_cls, 'sql'))
if not is_function:
continue
function_name = function_cls._meta.db_table
fields = tuple(
' '.join((n, _get_field_type(f))) for n, f in
get_fields_by_name(function_cls, '*').iteritems())
definition = function_cls.sql
full_name = u'{module}.{cls}'.format(
module=models_module.__name__,
cls=name)
try:
created = create_function(
connection, function_name, fields, definition)
except Exception, exc:
exc.function_cls = function_cls
exc.python_name = full_name
raise
else:
yield created, function_cls, full_name
def realize_deferred_projections(sender, *args, **kwargs):
"""Project any fields which were deferred pending model preparation."""
app_label = sender._meta.app_label
model_name = sender.__name__.lower()
pending = _DEFERRED_PROJECTIONS.pop((app_label, model_name), {})
for view_cls, field_names in pending.iteritems():
field_instances = get_fields_by_name(sender, *field_names)
for name, field in field_instances.iteritems():
# Only assign the field if the view does not already have an
# attribute or explicitly-defined field with that name.
if hasattr(view_cls, name) or hasfield(view_cls, name):
continue
copy.copy(field).contribute_to_class(view_cls, name)
def call(self, args=None):
"""Prepare the function for filtering by executing it with the
arguments passed.
"""
function_name, function_args = self.model._meta.db_table.split(u'(')
function_args = u'(' + function_args
model_name = self.model.__name__
app_label = self.model._meta.app_label
module = self.model.__module__
execute_arguments = ''
if args:
execute_arguments = ', '.join(unicode(a) for a in args)
execute_function = u'{name}({args})'.format(
name=function_name,
args=execute_arguments)
fields = get_fields_by_name(self.model, '*')
model = _create_model(
model_name, execute_function, fields, app_label, module)
return models.query.QuerySet(model, query.NonQuotingQuery(model))
