discourse/lib/bookmark_query.rb
Bianca Nenciu 5092c9804c
FIX: Return next bookmarks page only if it exists (#18139)
It used to return the next URL anyway which lead to an additional
request. On the frontend, if the result set was empty, it kept retrying
until at least one result was returned. This bug is fixed in this commit
too.
2022-09-01 13:04:00 +03:00

92 lines
3.0 KiB
Ruby

# frozen_string_literal: true
##
# Allows us to query Bookmark records for lists. Used mainly
# in the user/activity/bookmarks page.
class BookmarkQuery
def self.on_preload(&blk)
(@preload ||= Set.new) << blk
end
def self.preload(bookmarks, object)
preload_polymorphic_associations(bookmarks, object.guardian)
if @preload
@preload.each { |preload| preload.call(bookmarks, object) }
end
end
# These polymorphic associations are loaded to make the UserBookmarkListSerializer's
# life easier, which conditionally chooses the bookmark serializer to use based
# on the type, and we want the associations all loaded ahead of time to make
# sure we are not doing N+1s.
def self.preload_polymorphic_associations(bookmarks, guardian)
Bookmark.registered_bookmarkables.each do |registered_bookmarkable|
registered_bookmarkable.perform_preload(bookmarks, guardian)
end
end
attr_reader :guardian, :count
def initialize(user:, guardian: nil, params: {})
@user = user
@params = params
@guardian = guardian || Guardian.new(@user)
@page = @params[:page].to_i
@limit = @params[:limit].present? ? @params[:limit].to_i : @params[:per_page]
@count = 0
end
def list_all(&blk)
search_term = @params[:q]
ts_query = search_term.present? ? Search.ts_query(term: search_term) : nil
search_term_wildcard = search_term.present? ? "%#{search_term}%" : nil
queries = Bookmark.registered_bookmarkables.map do |bookmarkable|
interim_results = bookmarkable.perform_list_query(@user, @guardian)
# this could occur if there is some security reason that the user cannot
# access the bookmarkables that they have bookmarked, e.g. if they had 1 bookmark
# on a topic and that topic was moved into a private category
next if interim_results.blank?
if search_term.present?
interim_results = bookmarkable.perform_search_query(
interim_results, search_term_wildcard, ts_query
)
end
# this is purely to make the query easy to read and debug, otherwise it's
# all mashed up into a massive ball in MiniProfiler :)
"---- #{bookmarkable.model.to_s} bookmarkable ---\n\n #{interim_results.to_sql}"
end.compact
# same for interim results being blank, the user might have been locked out
# from all their various bookmarks, in which case they will see nothing and
# no further pagination/ordering/etc is required
return [] if queries.empty?
union_sql = queries.join("\n\nUNION\n\n")
results = Bookmark.select("bookmarks.*").from("(\n\n#{union_sql}\n\n) as bookmarks")
results = results.order(
"(CASE WHEN bookmarks.pinned THEN 0 ELSE 1 END),
bookmarks.reminder_at ASC,
bookmarks.updated_at DESC"
)
@count = results.count
if @page.positive?
results = results.offset(@page * @params[:per_page])
end
if updated_results = blk&.call(results)
results = updated_results
end
results = results.limit(@limit).to_a
BookmarkQuery.preload(results, self)
results
end
end