django-orchestra/orchestra/apps/orders/helpers.py

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2014-07-18 15:32:27 +00:00
import inspect
from orchestra.apps.accounts.models import Account
def search_for_related(origin, max_depth=2):
"""
Introspects origin object and return the first related service object
WARNING this is NOT an exhaustive search but a compromise between cost and
flexibility. A more comprehensive approach may be considered if
a use-case calls for it.
"""
def related_iterator(node):
for field in node._meta.virtual_fields:
if hasattr(field, 'ct_field'):
yield getattr(node, field.name)
for field in node._meta.fields:
if field.rel:
yield getattr(node, field.name)
# BFS model relation transversal
queue = [[origin]]
while queue:
models = queue.pop(0)
if len(models) > max_depth:
return None
node = models[-1]
if len(models) > 1:
if hasattr(node, 'account') or isinstance(node, Account):
return node
for related in related_iterator(node):
if related not in models:
new_models = list(models)
new_models.append(related)
queue.append(new_models)