def poll_stations_for(request, const_name, page_num):
const_name = const_name.upper()
key = "%s-stations-info" % const_name
#stn_info is a dict contains the list of stations and the jump to alphabetical dict
stn_info = memcache.get(key)
if stn_info is None:
logger.info("poll station list for '%s' not found in memcache." % const_name)
list = []
res = PollStation.gql("where belongsTo = :1 order by name ASC", const_name)
#create a map that will hold a "jump to" page number alphabetically
jump_to = {}
#loop counter, start at items per page so that page number starts at 1
counter = items_per_page
#hold letters already seen
letter_set = []
for stn in res:
counter = counter + 1
list.append(stn)
#populate map if first letter not present
#find out if key exists, record only first occurrence
if stn.nameStartsWith not in letter_set:
letter_set.append(stn.nameStartsWith)
page_to = counter / items_per_page
if page_to not in jump_to:
#create a list that holds all letters starting on same page
jump_to[page_to] = [stn.nameStartsWith]
else:#add to existing letter starting on this page
jump_to[page_to].append(stn.nameStartsWith)
#logger.info(jump_to)
memcache.add(key, {'stations':list, 'jump_to':jump_to})
else:#retrieve from memcache dict
list = stn_info['stations']
jump_to = stn_info['jump_to']
if len(list) == 0:#not found
err_msg = "No Poll stations were found for '%s'" % const_name
return render_to_response('kura_web/constituency-stations-view.html', {'error_message': err_msg, 'const_name': const_name})
else:
#poll station list found in memcache of db
return render_to_response('kura_web/constituency-stations-view.html',
{'const_name': const_name, 'page':page_object_list(list, page_num), 'jump_to':jump_to})
def retrieve_station_from_memcache_or_db(const_name, stn_name):
""" Retrieve polling station from memcache if it exists. If not, try the datastore """
#check if any arg is none and return none TODO - is that the best way
if const_name is None or stn_name is None:
logger.error("const_name or stn_name is None. Return None")
return None
#check if poll station had been fetched into memcache
stn_key = "poll-station-%s-%s" % (stn_name, const_name)
stn = memcache.get(stn_key)
if (stn is None): #not in memcache, fetch from db
logger.info("key %s not found in memcache" % stn_key),
#expects one result TODO, more that one result should not break the app
stn_res = PollStation.gql("where belongsTo=:cn and name=:nm", cn=const_name, nm=stn_name).fetch(1)
if (len(stn_res)) == 0:#polling station, const combi not found
logger.info("%s-%s not found" % (stn_name, const_name))
return None
else:
#retrieve first poll station from result list
memcache.set(stn_key, stn_res[0])
return stn_res[0]
else:
return stn#from memcache
