def process_stories(clusters):
"""
Takes clusters of node uuids and
builds, modifies, and deletes stories out of them.
`clusters` comes in as a list of lists, where sublists' members are article node ids.
e.g::
[[1,2,3,4,5],[6,7,8,9]]
"""
story_map = {}
existing = {}
# Yikes this might be too much
# TODO Should probably preserve existing story node id composition separately.
for s in Story.query.all():
story_map[s.id] = s
existing[s.id] = [e.id for e in s.events]
# Figure out which stories to update, delete, and create.
to_update, to_create, to_delete, unchanged = triage(existing, clusters)
for e_ids in to_create:
events = Event.query.filter(Event.id.in_(e_ids)).order_by(Event.created_at.desc()).all()
story = Story(events)
story.created_at = events[0].created_at
story.updated_at = events[-1].created_at
# TODO need a better way of coming up with a story title.
# Perhaps the easiest way if stories just don't have titles and are just groupings of events.
# For now, just using the latest event title and image.
story.title = events[0].title
story.image = events[0].image
db.session.add(story)
for s_id, e_ids in to_update.items():
s = story_map[s_id]
events = Event.query.filter(Event.id.in_(e_ids)).order_by(Event.created_at.desc()).all()
s.members = events
s.title = events[0].title
s.image = events[0].image
s.update()
for s_id in to_delete:
db.session.delete(story_map[s_id])
db.session.commit()
# Delete any stories that no longer have events.
# http://stackoverflow.com/a/7954618/1097920
Story.query.filter(~Story.members.any()).delete(synchronize_session='fetch')
def _create_dated_story(self):
datetime_A = datetime.utcnow() - timedelta(days=1)
datetime_B = datetime.utcnow() - timedelta(days=5)
article_a = fac.article(title='The Illiad', text='The Illiad has Argos in it.')
event_a = Event([article_a])
event_a.created_at = datetime_A
article_b = fac.article(title='The Illiad', text='The Illiad has Argos in it.')
event_b = Event([article_b])
event_b.created_at = datetime_B
article_c = fac.article(title='The Illiad', text='The Illiad has Argos in it.')
event_c = Event([article_c])
event_c.created_at = datetime_A
story = Story([event_a, event_b, event_c])
self.db.session.add(story)
self.db.session.commit()
return story, datetime_A, datetime_B
