Merge branch '34533-speed-up-group-project-authorizations' into 'master'

Speed up Group#user_ids_for_project_authorizations

Closes #36182

See merge request !13508

3 files changed, 51 insertions, 8 deletions

diff --git a/app/models/group.rb b/app/models/group.rb
index bd5735ed82e..2816a68257c 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -212,21 +212,39 @@ class Group < Namespace
   end
 
   def user_ids_for_project_authorizations
-    users_with_parents.pluck(:id)
+    members_with_parents.pluck(:user_id)
   end
 
   def members_with_parents
-    GroupMember.active.where(source_id: ancestors.pluck(:id).push(id)).where.not(user_id: nil)
+    # Avoids an unnecessary SELECT when the group has no parents
+    source_ids =
+      if parent_id
+        self_and_ancestors.reorder(nil).select(:id)
+      else
+        id
+      end
+
+    GroupMember
+      .active_without_invites
+      .where(source_id: source_ids)
+  end
+
+  def members_with_descendants
+    GroupMember
+      .active_without_invites
+      .where(source_id: self_and_descendants.reorder(nil).select(:id))
   end
 
   def users_with_parents
-    User.where(id: members_with_parents.select(:user_id))
+    User
+      .where(id: members_with_parents.select(:user_id))
+      .reorder(nil)
   end
 
   def users_with_descendants
-    members_with_descendants = GroupMember.non_request.where(source_id: descendants.pluck(:id).push(id))
-
-    User.where(id: members_with_descendants.select(:user_id))
+    User
+      .where(id: members_with_descendants.select(:user_id))
+      .reorder(nil)
   end
 
   def max_member_access_for_user(user)
diff --git a/app/models/member.rb b/app/models/member.rb
index b26b5017183..ee2cb13697b 100644
--- a/app/models/member.rb
+++ b/app/models/member.rb
@@ -41,9 +41,20 @@ class Member < ActiveRecord::Base
     is_external_invite = arel_table[:user_id].eq(nil).and(arel_table[:invite_token].not_eq(nil))
     user_is_active = User.arel_table[:state].eq(:active)
 
-    includes(:user).references(:users)
-      .where(is_external_invite.or(user_is_active))
+    user_ok = Arel::Nodes::Grouping.new(is_external_invite).or(user_is_active)
+
+    left_join_users
+      .where(user_ok)
+      .where(requested_at: nil)
+      .reorder(nil)
+  end
+
+  # Like active, but without invites. For when a User is required.
+  scope :active_without_invites, -> do
+    left_join_users
+      .where(users: { state: 'active' })
       .where(requested_at: nil)
+      .reorder(nil)
   end
 
   scope :invite, -> { where.not(invite_token: nil) }
diff --git a/app/models/namespace.rb b/app/models/namespace.rb
index 6073fb94a3f..e7bc1d1b080 100644
--- a/app/models/namespace.rb
+++ b/app/models/namespace.rb
@@ -156,6 +156,14 @@ class Namespace < ActiveRecord::Base
       .base_and_ancestors
   end
 
+  def self_and_ancestors
+    return self.class.where(id: id) unless parent_id
+
+    Gitlab::GroupHierarchy
+      .new(self.class.where(id: id))
+      .base_and_ancestors
+  end
+
   # Returns all the descendants of the current namespace.
   def descendants
     Gitlab::GroupHierarchy
@@ -163,6 +171,12 @@ class Namespace < ActiveRecord::Base
       .base_and_descendants
   end
 
+  def self_and_descendants
+    Gitlab::GroupHierarchy
+      .new(self.class.where(id: id))
+      .base_and_descendants
+  end
+
   def user_ids_for_project_authorizations
     [owner_id]
   end