From 28e6af88aa16a33717dbdbe870a8423300aef042 Mon Sep 17 00:00:00 2001 From: Sean McGivern Date: Tue, 2 Oct 2018 15:29:45 +0100 Subject: Fix N+1 for notification recipients on private projects MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If we don't call #to_a, we're relying on the members already being loaded from elsewhere. Otherwise we'll do a separate query for each user: [1] pry(main)> Project.first.team.members.include?(User.first) Project Load (0.7ms) SELECT "projects".* FROM "projects" ORDER BY "projects"."id" ASC LIMIT 1 ↳ (pry):3 User Load (1.8ms) SELECT "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT 1 ↳ (pry):3 User Exists (0.6ms) SELECT 1 AS one FROM "users" INNER JOIN "project_authorizations" ON "users"."id" = "project_authorizations"."user_id" WHERE "project_authorizations"."project_id" = $1 AND "users"."id" = $2 LIMIT 1 [["project_id", 1], ["id", 1]] ↳ (pry):3 => true [2] pry(main)> Project.first.team.members.to_a.include?(User.first) Project Load (12.8ms) SELECT "projects".* FROM "projects" ORDER BY "projects"."id" ASC LIMIT 1 ↳ (pry):1 User Load (9.6ms) SELECT "users".* FROM "users" INNER JOIN "project_authorizations" ON "users"."id" = "project_authorizations"."user_id" WHERE "project_authorizations"."project_id" = $1 [["project_id", 1]] ↳ (pry):1 User Load (0.6ms) SELECT "users".* FROM "users" ORDER BY "users"."id" ASC LIMIT 1 ↳ (pry):1 => true --- app/policies/project_policy.rb | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'app/policies/project_policy.rb') diff --git a/app/policies/project_policy.rb b/app/policies/project_policy.rb index d0e84b1aa38..f2c246cd969 100644 --- a/app/policies/project_policy.rb +++ b/app/policies/project_policy.rb @@ -390,7 +390,11 @@ class ProjectPolicy < BasePolicy greedy_load_subject ||= !@user.persisted? if greedy_load_subject - project.team.members.include?(user) + # We want to load all the members with one query. Calling #include? on + # project.team.members will perform a separate query for each user, unless + # project.team.members was loaded before somewhere else. Calling #to_a + # ensures it's always loaded before checking for membership. + project.team.members.to_a.include?(user) else # otherwise we just make a specific query for # this particular user. -- cgit v1.2.1