discourse/app/models/tag.rb

75 lines
2.3 KiB
Ruby

class Tag < ActiveRecord::Base
validates :name, presence: true, uniqueness: true
has_many :tag_users # notification settings
has_many :topic_tags, dependent: :destroy
has_many :topics, through: :topic_tags
has_many :category_tags, dependent: :destroy
has_many :categories, through: :category_tags
has_many :tag_group_memberships
has_many :tag_groups, through: :tag_group_memberships
COUNT_ARG = "topic_tags.id"
# Apply more activerecord filters to the tags_by_count_query, and then
# fetch the result with .count(Tag::COUNT_ARG).
#
# e.g., Tag.tags_by_count_query.where("topics.category_id = ?", category.id).count(Tag::COUNT_ARG)
def self.tags_by_count_query(opts={})
q = Tag.joins("LEFT JOIN topic_tags ON tags.id = topic_tags.tag_id")
.joins("LEFT JOIN topics ON topics.id = topic_tags.topic_id")
.group("tags.id, tags.name")
.order('count_topic_tags_id DESC')
q = q.limit(opts[:limit]) if opts[:limit]
q
end
def self.category_tags_by_count_query(category, opts={})
tags_by_count_query(opts).where("tags.id in (select tag_id from category_tags where category_id = ?)", category.id)
.where("topics.category_id = ?", category.id)
end
def self.top_tags(limit_arg: nil, category: nil, guardian: nil)
limit = limit_arg || SiteSetting.max_tags_in_filter_list
scope_category_ids = (guardian||Guardian.new).allowed_category_ids
if category
scope_category_ids &= ([category.id] + category.subcategories.pluck(:id))
end
tags = DiscourseTagging.filter_allowed_tags(
tags_by_count_query(limit: limit).where("topics.category_id in (?)", scope_category_ids),
nil, # Don't pass guardian. You might not be able to use some tags, but should still be able to see where they've been used.
category: category
)
tags.count(COUNT_ARG).map {|name, _| name}
end
def self.include_tags?
SiteSetting.tagging_enabled && SiteSetting.show_filter_by_tag
end
def full_url
"#{Discourse.base_url}/tags/#{self.name}"
end
end
# == Schema Information
#
# Table name: tags
#
# id :integer not null, primary key
# name :string not null
# topic_count :integer default(0), not null
# created_at :datetime
# updated_at :datetime
#
# Indexes
#
# index_tags_on_name (name) UNIQUE
#