Mercurial > public > sg101
annotate gpp/news/utils.py @ 552:9e42e6618168
For bitbucket issue #2, tweak the admin settings for the Post model to
reduce slow queries. Define our own queryset() method so we can control the
select_related(), and not have it cascade from post to topics to forums to
categories. Removed 'topic' from list_display because MySQL still sucked with
2 inner joins. Now it seems to be tolerable with only one join to User.
| author | Brian Neal <bgneal@gmail.com> |
|---|---|
| date | Wed, 25 Jan 2012 20:07:03 -0600 |
| parents | 24f1230f3ee3 |
| children |
| rev | line source |
|---|---|
| bgneal@399 | 1 """ |
| bgneal@399 | 2 Common utility/helper code for the news app. |
| bgneal@399 | 3 |
| bgneal@399 | 4 """ |
| bgneal@399 | 5 from django.contrib.contenttypes.models import ContentType |
| bgneal@399 | 6 |
| bgneal@399 | 7 from comments.models import Comment |
| bgneal@399 | 8 from tagging.models import TaggedItem |
| bgneal@399 | 9 from news.models import Story |
| bgneal@399 | 10 |
| bgneal@399 | 11 |
| bgneal@399 | 12 def attach_extra_attrs(stories): |
| bgneal@399 | 13 """ |
| bgneal@399 | 14 For each story in the input stories list, attach 2 new attributes: |
| bgneal@399 | 15 tag_list and comment_count. The tags and comment count info is pulled from |
| bgneal@399 | 16 the database in bulk. This saves database queries when lots of news |
| bgneal@399 | 17 stories are displayed at once. For best results, use ".defer('tags')" |
| bgneal@399 | 18 when retrieve the stories from the database. |
| bgneal@399 | 19 |
| bgneal@399 | 20 """ |
| bgneal@399 | 21 stories_dict = dict((story.id, story) for story in stories) |
| bgneal@399 | 22 story_ids = stories_dict.keys() |
| bgneal@399 | 23 |
| bgneal@399 | 24 # Get all the tags out in one query |
| bgneal@399 | 25 ct = ContentType.objects.get_for_model(Story) |
| bgneal@399 | 26 tagged_items = TaggedItem.objects.filter(content_type=ct, |
| bgneal@399 | 27 object_id__in=story_ids).select_related('tag') |
| bgneal@399 | 28 |
| bgneal@399 | 29 for story in stories_dict.values(): |
| bgneal@399 | 30 story.tag_list = [] |
| bgneal@399 | 31 story.comment_count = 0 |
| bgneal@399 | 32 |
| bgneal@399 | 33 # attach tags |
| bgneal@399 | 34 for item in tagged_items: |
| bgneal@399 | 35 stories_dict[item.object_id].tag_list.append(item.tag.name) |
| bgneal@399 | 36 |
| bgneal@399 | 37 # Now get all the comment counts out in one fell swoop |
| bgneal@399 | 38 |
| bgneal@399 | 39 story_ids = Comment.objects.filter(content_type=ct, |
| bgneal@399 | 40 object_id__in=story_ids).values_list('object_id', flat=True) |
| bgneal@399 | 41 |
| bgneal@399 | 42 # compute comment_count |
| bgneal@399 | 43 for story_id in story_ids: |
| bgneal@399 | 44 stories_dict[story_id].comment_count += 1 |