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annotate forums/unread.py @ 679:89b240fe9297

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For Django 1.5.2: import json; django.utils.simplejson is deprecated.
author Brian Neal <bgneal@gmail.com>
date Thu, 15 Aug 2013 20:14:33 -0500
parents ee87ea74d46b
children
rev   line source
bgneal@113 1 """
bgneal@307 2 This file contains routines for implementing the "has unread" feature.
bgneal@113 3 Forums, topics, and posts are displayed with a visual indication if they have
bgneal@113 4 been read or not.
bgneal@113 5 """
bgneal@113 6 import datetime
bgneal@370 7 import logging
bgneal@113 8
bgneal@370 9 from django.db import IntegrityError
bgneal@167 10
bgneal@167 11 from forums.models import ForumLastVisit, TopicLastVisit, Topic, Forum
bgneal@113 12
bgneal@113 13
bgneal@307 14 THRESHOLD = datetime.timedelta(days=14)
bgneal@113 15
bgneal@114 16 #######################################################################
bgneal@113 17
bgneal@113 18 def get_forum_unread_status(qs, user):
bgneal@113 19 if not user.is_authenticated():
bgneal@113 20 for forum in qs:
bgneal@113 21 forum.has_unread = False
bgneal@113 22 return
bgneal@113 23
bgneal@113 24 now = datetime.datetime.now()
bgneal@113 25 min_date = now - THRESHOLD
bgneal@113 26
bgneal@113 27 # retrieve ForumLastVisit records in one SQL query
bgneal@113 28 forum_ids = [forum.id for forum in qs]
bgneal@307 29 flvs = ForumLastVisit.objects.filter(user=user,
bgneal@113 30 forum__in=forum_ids).select_related()
bgneal@113 31 flvs = dict([(flv.forum.id, flv) for flv in flvs])
bgneal@113 32
bgneal@113 33 for forum in qs:
bgneal@113 34 # Edge case: forum has no posts
bgneal@113 35 if forum.last_post is None:
bgneal@113 36 forum.has_unread = False
bgneal@113 37 continue
bgneal@113 38
bgneal@113 39 # Get the ForumLastVisit record
bgneal@113 40 if forum.id in flvs:
bgneal@113 41 flv = flvs[forum.id]
bgneal@113 42 else:
bgneal@113 43 # One doesn't exist, create a default one for next time,
bgneal@113 44 # mark it as having no unread topics, and bail.
bgneal@113 45 flv = ForumLastVisit(user=user, forum=forum)
bgneal@113 46 flv.begin_date = now
bgneal@113 47 flv.end_date = now
bgneal@370 48
bgneal@370 49 # There is a race condition and sometimes another thread
bgneal@370 50 # saves a record before we do; just log this if it happens.
bgneal@370 51 try:
bgneal@370 52 flv.save()
bgneal@370 53 except IntegrityError:
bgneal@370 54 logging.exception('get_forum_unread_status')
bgneal@370 55
bgneal@113 56 forum.has_unread = False
bgneal@113 57 continue
bgneal@113 58
bgneal@113 59 # If the last visit record was too far in the past,
bgneal@113 60 # catch that user up and mark as no unreads.
bgneal@113 61 if now - flv.end_date > THRESHOLD:
bgneal@113 62 forum.catchup(user, flv)
bgneal@113 63 forum.has_unread = False
bgneal@113 64 continue
bgneal@113 65
bgneal@113 66 # Check the easy cases first. Check the last_post in the
bgneal@113 67 # forum. If created after the end_date in our window, there
bgneal@113 68 # are new posts. Likewise, if before the begin_date in our window,
bgneal@113 69 # there are no new posts.
bgneal@113 70 if forum.last_post.creation_date > flv.end_date:
bgneal@113 71 forum.has_unread = True
bgneal@113 72 elif forum.last_post.creation_date < flv.begin_date:
bgneal@113 73 if not flv.is_caught_up():
bgneal@113 74 forum.catchup(user, flv)
bgneal@113 75 forum.has_unread = False
bgneal@113 76 else:
bgneal@113 77 # Going to have to examine the topics in our window.
bgneal@113 78 # First adjust our window if it is too old.
bgneal@113 79 if now - flv.begin_date > THRESHOLD:
bgneal@113 80 flv.begin_date = min_date
bgneal@113 81 flv.save()
bgneal@113 82 TopicLastVisit.objects.filter(user=user, topic__forum=forum,
bgneal@113 83 last_visit__lt=min_date).delete()
bgneal@113 84
bgneal@307 85 topics = Topic.objects.filter(forum=forum,
bgneal@420 86 update_date__gt=flv.begin_date)
bgneal@408 87 tracked_topics = TopicLastVisit.objects.filter(
bgneal@408 88 user=user,
bgneal@408 89 topic__forum=forum,
bgneal@408 90 last_visit__gt=flv.begin_date).select_related('topic')
bgneal@113 91
bgneal@113 92 # If the number of topics created since our window was started
bgneal@113 93 # is greater than the tracked topic records, then there are new
bgneal@113 94 # posts.
bgneal@113 95 if topics.count() > tracked_topics.count():
bgneal@113 96 forum.has_unread = True
bgneal@113 97 continue
bgneal@113 98
bgneal@408 99 tracked_dict = dict((t.topic.id, t) for t in tracked_topics)
bgneal@113 100
bgneal@113 101 for topic in topics:
bgneal@113 102 if topic.id in tracked_dict:
bgneal@113 103 if topic.update_date > tracked_dict[topic.id].last_visit:
bgneal@113 104 forum.has_unread = True
bgneal@407 105 break
bgneal@113 106 else:
bgneal@113 107 forum.has_unread = True
bgneal@407 108 break
bgneal@407 109 else:
bgneal@407 110 # If we made it through the above loop without breaking out,
bgneal@407 111 # then we are all caught up.
bgneal@407 112 forum.catchup(user, flv)
bgneal@407 113 forum.has_unread = False
bgneal@114 114
bgneal@114 115 #######################################################################
bgneal@114 116
bgneal@114 117 def get_topic_unread_status(forum, topics, user):
bgneal@114 118
bgneal@114 119 # Edge case: no topics
bgneal@114 120 if forum.last_post is None:
bgneal@114 121 return
bgneal@114 122
bgneal@114 123 # This service isn't provided to unauthenticated users
bgneal@114 124 if not user.is_authenticated():
bgneal@114 125 for topic in topics:
bgneal@114 126 topic.has_unread = False
bgneal@114 127 return
bgneal@114 128
bgneal@114 129 now = datetime.datetime.now()
bgneal@114 130
bgneal@114 131 # Get the ForumLastVisit record
bgneal@114 132 try:
bgneal@114 133 flv = ForumLastVisit.objects.get(forum=forum, user=user)
bgneal@114 134 except ForumLastVisit.DoesNotExist:
bgneal@114 135 # One doesn't exist, create a default one for next time,
bgneal@114 136 # mark it as having no unread topics, and bail.
bgneal@114 137 flv = ForumLastVisit(user=user, forum=forum)
bgneal@114 138 flv.begin_date = now
bgneal@114 139 flv.end_date = now
bgneal@370 140
bgneal@370 141 # There is a race condition and sometimes another thread
bgneal@370 142 # saves a record before we do; just log this if it happens.
bgneal@370 143 try:
bgneal@370 144 flv.save()
bgneal@370 145 except IntegrityError:
bgneal@370 146 logging.exception('get_topic_unread_status')
bgneal@370 147
bgneal@114 148 for topic in topics:
bgneal@114 149 topic.has_unread = False
bgneal@114 150 return
bgneal@114 151
bgneal@114 152 # Are all the posts before our window? If so, all have been read.
bgneal@114 153 if forum.last_post.creation_date < flv.begin_date:
bgneal@114 154 for topic in topics:
bgneal@114 155 topic.has_unread = False
bgneal@114 156 return
bgneal@114 157
bgneal@114 158 topic_ids = [topic.id for topic in topics]
bgneal@114 159 tlvs = TopicLastVisit.objects.filter(user=user, topic__id__in=topic_ids)
bgneal@114 160 tlvs = dict([(tlv.topic.id, tlv) for tlv in tlvs])
bgneal@114 161
bgneal@114 162 # Otherwise we have to go through the topics one by one:
bgneal@114 163 for topic in topics:
bgneal@114 164 if topic.update_date < flv.begin_date:
bgneal@114 165 topic.has_unread = False
bgneal@114 166 elif topic.update_date > flv.end_date:
bgneal@114 167 topic.has_unread = True
bgneal@114 168 elif topic.id in tlvs:
bgneal@114 169 topic.has_unread = topic.update_date > tlvs[topic.id].last_visit
bgneal@114 170 else:
bgneal@114 171 topic.has_unread = True
bgneal@114 172
bgneal@114 173 #######################################################################
bgneal@114 174
bgneal@114 175 def get_post_unread_status(topic, posts, user):
bgneal@114 176 # This service isn't provided to unauthenticated users
bgneal@114 177 if not user.is_authenticated():
bgneal@114 178 for post in posts:
bgneal@114 179 post.unread = False
bgneal@114 180 return
bgneal@114 181
bgneal@114 182 # Get the ForumLastVisit record
bgneal@114 183 try:
bgneal@114 184 flv = ForumLastVisit.objects.get(forum=topic.forum, user=user)
bgneal@114 185 except ForumLastVisit.DoesNotExist:
bgneal@114 186 # One doesn't exist, all posts are old.
bgneal@114 187 for post in posts:
bgneal@114 188 post.unread = False
bgneal@114 189 return
bgneal@114 190
bgneal@114 191 # Are all the posts before our window? If so, all have been read.
bgneal@114 192 if topic.last_post.creation_date < flv.begin_date:
bgneal@114 193 for post in posts:
bgneal@114 194 post.unread = False
bgneal@114 195 return
bgneal@114 196
bgneal@114 197 # Do we have a topic last visit record for this topic?
bgneal@114 198
bgneal@114 199 try:
bgneal@114 200 tlv = TopicLastVisit.objects.get(user=user, topic=topic)
bgneal@114 201 except TopicLastVisit.DoesNotExist:
bgneal@114 202 # No we don't, we could be all caught up, or all are new
bgneal@114 203 for post in posts:
bgneal@114 204 post.unread = post.creation_date > flv.end_date
bgneal@114 205 else:
bgneal@114 206 for post in posts:
bgneal@114 207 post.unread = post.creation_date > tlv.last_visit
bgneal@167 208
bgneal@167 209 #######################################################################
bgneal@167 210
bgneal@167 211 def get_unread_topics(user):
bgneal@167 212 """Returns a list of topics the user hasn't read yet."""
bgneal@167 213
bgneal@167 214 # This is only available to authenticated users
bgneal@167 215 if not user.is_authenticated():
bgneal@167 216 return []
bgneal@167 217
bgneal@167 218 now = datetime.datetime.now()
bgneal@167 219
bgneal@167 220 # Obtain list of forums the user can view
bgneal@167 221 forums = Forum.objects.forums_for_user(user)
bgneal@167 222
bgneal@167 223 # Get forum last visit records for the forum ids
bgneal@167 224 flvs = ForumLastVisit.objects.filter(user=user,
bgneal@167 225 forum__in=forums).select_related()
bgneal@167 226 flvs = dict([(flv.forum.id, flv) for flv in flvs])
bgneal@167 227
bgneal@167 228 unread_topics = []
bgneal@167 229 topics = Topic.objects.none()
bgneal@167 230 for forum in forums:
bgneal@167 231 # if the user hasn't visited the forum, create a last
bgneal@167 232 # visit record set to "now"
bgneal@167 233 if not forum.id in flvs:
bgneal@167 234 flv = ForumLastVisit(user=user, forum=forum, begin_date=now,
bgneal@167 235 end_date=now)
bgneal@167 236 flv.save()
bgneal@167 237 else:
bgneal@167 238 flv = flvs[forum.id]
bgneal@167 239 topics |= Topic.objects.filter(forum=forum,
bgneal@168 240 update_date__gt=flv.begin_date).order_by('-update_date').select_related(
bgneal@168 241 'forum', 'user', 'last_post', 'last_post__user')
bgneal@167 242
bgneal@167 243 if topics is not None:
bgneal@167 244 # get all topic last visit records for the topics of interest
bgneal@167 245
bgneal@167 246 tlvs = TopicLastVisit.objects.filter(user=user, topic__in=topics)
bgneal@167 247 tlvs = dict([(tlv.topic.id, tlv) for tlv in tlvs])
bgneal@167 248
bgneal@167 249 for topic in topics:
bgneal@167 250 if topic.id in tlvs:
bgneal@167 251 tlv = tlvs[topic.id]
bgneal@167 252 if topic.update_date > tlv.last_visit:
bgneal@167 253 unread_topics.append(topic)
bgneal@167 254 else:
bgneal@167 255 unread_topics.append(topic)
bgneal@167 256
bgneal@167 257 return unread_topics