Set member_namespace_id when creating a Member

app/models/member.rb

@@ -181,6 +181,7 @@ class Member < ApplicationRecord
 
   scope :on_project_and_ancestors, ->(project) { where(source: [project] + project.ancestors) }
 
+  before_validation :set_member_namespace_id, on: :create
   before_validation :generate_invite_token, on: :create, if: -> (member) { member.invite_email.present? && !member.invite_accepted_at? }
 
   after_create :send_invite, if: :invite?, unless: :importing?
@@ -381,6 +382,12 @@ class Member < ApplicationRecord
 
   private
 
+  # TODO: https://gitlab.com/groups/gitlab-org/-/epics/7054
+  # temporary until we can we properly remove the source columns
+  def set_member_namespace_id
+    self.member_namespace_id = self.source_id
+  end
+
   def access_level_inclusion
     return if access_level.in?(Gitlab::Access.all_values)
 

app/models/members/project_member.rb

@@ -118,6 +118,13 @@ class ProjectMember < Member
     # rubocop:enable CodeReuse/ServiceClass
   end
 
+  # TODO: https://gitlab.com/groups/gitlab-org/-/epics/7054
+  # temporary until we can we properly remove the source columns
+  override :set_member_namespace_id
+  def set_member_namespace_id
+    self.member_namespace_id = project&.project_namespace_id
+  end
+
   def send_invite
     run_after_commit_or_now { notification_service.invite_project_member(self, @raw_invite_token) }
 

spec/models/member_spec.rb

@@ -894,4 +894,15 @@ RSpec.describe Member do
       end
     end
   end
+
+  describe '#set_member_namespace_id' do
+    let(:group) { create(:group) }
+    let(:member) { create(:group_member, group: group) }
+
+    describe 'on create' do
+      it 'sets the member_namespace_id' do
+        expect(member.member_namespace_id).to eq group.id
+      end
+    end
+  end
 end

spec/models/members/project_member_spec.rb

@@ -257,4 +257,15 @@ RSpec.describe ProjectMember do
       it_behaves_like 'calls AuthorizedProjectUpdate::UserRefreshFromReplicaWorker with a delay to update project authorizations'
     end
   end
+
+  describe '#set_member_namespace_id' do
+    let(:project) { create(:project) }
+    let(:member) { create(:project_member, project: project) }
+
+    context 'on create' do
+      it 'sets the member_namespace_id' do
+        expect(member.member_namespace_id).to eq project.project_namespace_id
+      end
+    end
+  end
 end