django-orchestra/orchestra/models/utils.py

69 lines
2.2 KiB
Python

from django.conf import settings
from django.db.models import loading, Manager
from django.utils import importlib
def get_model(label, import_module=True):
app_label, model_name = label.split('.')
model = loading.get_model(app_label, model_name)
if model is None:
# Sometimes the models module is not yet imported
for app in settings.INSTALLED_APPS:
if app.endswith(app_label):
app_label = app
importlib.import_module('%s.%s' % (app_label, 'admin'))
return loading.get_model(*label.split('.'))
return model
def queryset_as_manager(qs_class):
# Allow chained managers
# Based on http://djangosnippets.org/snippets/562/#c2486
class ChainerManager(Manager):
def __init__(self):
super(ChainerManager,self).__init__()
self.queryset_class = qs_class
def get_query_set(self):
return self.queryset_class(self.model)
def __getattr__(self, attr, *args):
try:
return getattr(type(self), attr, *args)
except AttributeError:
return getattr(self.get_query_set(), attr, *args)
return ChainerManager()
def get_field_value(obj, field_name):
names = field_name.split('__')
rel = getattr(obj, names.pop(0))
for name in names:
try:
rel = getattr(rel, name)
except AttributeError:
# maybe is a query manager
rel = getattr(rel.get(), name)
return rel
def get_model_field_path(origin, target):
""" BFS search on model relaion fields """
queue = []
queue.append(([origin], []))
while queue:
model, path = queue.pop(0)
if len(model) > 4:
msg = "maximum recursion depth exceeded while looking for %s"
raise RuntimeError(msg % target)
node = model[-1]
if node == target:
return path
for field in node._meta.fields:
if field.rel:
new_model = list(model)
new_model.append(field.rel.to)
new_path = list(path)
new_path.append(field.name)
queue.append((new_model, new_path))