discourse/app/models/user_tracking_state.rb

84 lines
3.1 KiB
Ruby

# this class is used to mirror unread and new status back to end users
# in JavaScript there is a mirror class that is kept in-sync using the mssage bus
# the allows end users to always know which topics have unread posts in them
# and which topics are new
class UserTrackingState
include ActiveModel::SerializerSupport
CHANNEL = "/user-tracking"
attr_accessor :user_id, :topic_id, :highest_post_number, :last_read_post_number, :created_at, :category_name
MessageBus.client_filter(CHANNEL) do |user_id, message|
if user_id
UserTrackingState.new(User.find(user_id)).filter(message)
else
nil
end
end
def self.trigger_change(topic_id, post_number, user_id=nil)
MessageBus.publish(CHANNEL, "CHANGE", user_ids: [user_id].compact)
end
def self.treat_as_new_topic_clause
User.where("CASE
WHEN COALESCE(u.new_topic_duration_minutes, :default_duration) = :always THEN u.created_at
WHEN COALESCE(u.new_topic_duration_minutes, :default_duration) = :last_visit THEN COALESCE(u.previous_visit_at,u.created_at)
ELSE (:now::timestamp - INTERVAL '1 MINUTE' * COALESCE(u.new_topic_duration_minutes, :default_duration))
END",
now: DateTime.now,
last_visit: User::NewTopicDuration::LAST_VISIT,
always: User::NewTopicDuration::ALWAYS,
default_duration: SiteSetting.new_topic_duration_minutes
).where_values[0]
end
def self.report(user_ids, topic_id = nil)
# Sam: this is a hairy report, in particular I need custom joins and fancy conditions
# Dropping to sql_builder so I can make sense of it.
#
# Keep in mind, we need to be able to filter on a GROUP of users, and zero in on topic
# all our existing scope work does not do this
#
# This code needs to be VERY efficient as it is triggered via the message bus and may steal
# cycles from usual requests
#
unread = TopicQuery.unread_filter(Topic).where_values.join(" AND ")
new = TopicQuery.new_filter(Topic, "xxx").where_values.join(" AND ").gsub!("'xxx'", treat_as_new_topic_clause)
sql = <<SQL
SELECT u.id AS user_id, topics.id AS topic_id, topics.created_at, highest_post_number, last_read_post_number, c.name AS category_name
FROM users u
FULL OUTER JOIN topics ON 1=1
LEFT JOIN topic_users tu ON tu.topic_id = topics.id AND tu.user_id = u.id
LEFT JOIN categories c ON c.id = topics.category_id
WHERE u.id IN (:user_ids) AND
topics.archetype <> 'private_message' AND
((#{unread}) OR (#{new})) AND
(topics.visible OR u.admin OR u.moderator) AND
topics.deleted_at IS NULL AND
( category_id IS NULL OR NOT c.secure OR category_id IN (
SELECT c2.id FROM categories c2
JOIN category_groups cg ON cg.category_id = c2.id
JOIN group_users gu ON gu.user_id = u.id AND cg.group_id = gu.group_id
WHERE c2.secure )
)
SQL
if topic_id
sql << " AND topics.id = :topic_id"
end
SqlBuilder.new(sql)
.map_exec(UserTrackingState, user_ids: user_ids, topic_id: topic_id)
end
end