debian-mirror-gitlab/lib/gitlab/issuable_metadata.rb
2020-06-23 00:09:42 +05:30

97 lines
3 KiB
Ruby

# frozen_string_literal: true
module Gitlab
class IssuableMetadata
include Gitlab::Utils::StrongMemoize
# data structure to store issuable meta data like
# upvotes, downvotes, notes and closing merge requests counts for issues and merge requests
# this avoiding n+1 queries when loading issuable collections on frontend
IssuableMeta = Struct.new(:upvotes, :downvotes, :user_notes_count, :mrs_count) do
def merge_requests_count(user = nil)
mrs_count
end
end
attr_reader :current_user, :issuable_collection
def initialize(current_user, issuable_collection)
@current_user = current_user
@issuable_collection = issuable_collection
validate_collection!
end
def data
return {} if issuable_ids.empty?
issuable_ids.each_with_object({}) do |id, issuable_meta|
issuable_meta[id] = metadata_for_issuable(id)
end
end
private
def metadata_for_issuable(id)
downvotes = group_issuable_votes_count.find { |votes| votes.awardable_id == id && votes.downvote? }
upvotes = group_issuable_votes_count.find { |votes| votes.awardable_id == id && votes.upvote? }
notes = grouped_issuable_notes_count.find { |notes| notes.noteable_id == id }
merge_requests = grouped_issuable_merge_requests_count.find { |mr| mr.first == id }
IssuableMeta.new(
upvotes.try(:count).to_i,
downvotes.try(:count).to_i,
notes.try(:count).to_i,
merge_requests.try(:last).to_i
)
end
def validate_collection!
# ActiveRecord uses Object#extend for null relations.
if !(issuable_collection.singleton_class < ActiveRecord::NullRelation) &&
issuable_collection.respond_to?(:limit_value) &&
issuable_collection.limit_value.nil?
raise 'Collection must have a limit applied for preloading meta-data'
end
end
def issuable_ids
strong_memoize(:issuable_ids) do
# map has to be used here since using pluck or select will
# throw an error when ordering issuables by priority which inserts
# a new order into the collection.
# We cannot use reorder to not mess up the paginated collection.
issuable_collection.map(&:id)
end
end
def collection_type
# Supports relations or paginated arrays
issuable_collection.try(:model)&.name ||
issuable_collection.first&.model_name.to_s
end
def group_issuable_votes_count
strong_memoize(:group_issuable_votes_count) do
AwardEmoji.votes_for_collection(issuable_ids, collection_type)
end
end
def grouped_issuable_notes_count
strong_memoize(:grouped_issuable_notes_count) do
::Note.count_for_collection(issuable_ids, collection_type)
end
end
def grouped_issuable_merge_requests_count
strong_memoize(:grouped_issuable_merge_requests_count) do
if collection_type == 'Issue'
::MergeRequestsClosingIssues.count_for_collection(issuable_ids, current_user)
else
[]
end
end
end
end
end