def ba_from_request(request, ba=None):
"""
Given a GET request with location info, return balancing authority
name and model queryset.
Location info can be st (state), or ba (balancing authority).
Future support for lat+lng, zipcode, country code, etc.
Returns tuple of (string, QuerySet)
"""
if ba:
# use supplied ba
ba = ba.upper()
else:
# try state
state = request.GET.get('st', None)
if state:
state = state.upper()
ba = BALANCING_AUTHORITIES.get(state, None)
# try BA
else:
ba = request.GET.get('ba', None)
if ba:
ba = ba.upper()
# got nothing
try:
return ba, BA_MODELS[ba].objects.all()
except:
logging.debug('returning null BA')
return ba, None
