def set_live_promotions(links, weights, which=("cass", "permacache")):
if "permacache" in which:
timer = g.stats.get_timer("promote.set_live.permacache")
timer.start()
g.permacache.set(promotion_key(), (links, weights))
timer.stop()
if "cass" in which:
timer = g.stats.get_timer("promote.set_live.cass")
timer.start()
# First, figure out which subreddits have had ads recently
today = promo_datetime_now()
yesterday = today - timedelta(days=1)
tomorrow = today + timedelta(days=1)
promo_weights = PromotionWeights.get_campaigns(yesterday, tomorrow)
subreddit_names = set(p.sr_name for p in promo_weights)
subreddits = Subreddit._by_name(subreddit_names).values()
# Set the default for those subreddits to no ads
all_weights = {sr._id: [] for sr in subreddits}
# Mix in the currently live ads
all_weights.update(weights)
if '' in all_weights:
all_weights[LiveAdWeights.FRONT_PAGE] = all_weights.pop('')
LiveAdWeights.set_all_from_weights(all_weights)
timer.stop()
