Merge branch 'osw-delete-fork-relation-upon-visibility-change' into 'master'

Update fork network relations upon project visibility decrease

See merge request gitlab-org/gitlab!20466

app/models/merge_request.rb

@@ -199,6 +199,9 @@ class MergeRequest < ApplicationRecord
   scope :by_milestone, ->(milestone) { where(milestone_id: milestone) }
   scope :of_projects, ->(ids) { where(target_project_id: ids) }
   scope :from_project, ->(project) { where(source_project_id: project.id) }
+  scope :from_and_to_forks, ->(project) do
+    where('source_project_id <> target_project_id AND (source_project_id = ? OR target_project_id = ?)', project.id, project.id)
+  end
   scope :merged, -> { with_state(:merged) }
   scope :closed_and_merged, -> { with_states(:closed, :merged) }
   scope :open_and_closed, -> { with_states(:opened, :closed) }

app/models/project.rb

@@ -179,6 +179,7 @@ class Project < ApplicationRecord
   has_one :forked_from_project, through: :fork_network_member
   has_many :forked_to_members, class_name: 'ForkNetworkMember', foreign_key: 'forked_from_project_id'
   has_many :forks, through: :forked_to_members, source: :project, inverse_of: :forked_from_project
+  has_many :fork_network_projects, through: :fork_network, source: :projects
 
   has_one :import_state, autosave: true, class_name: 'ProjectImportState', inverse_of: :project
   has_one :import_export_upload, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
@@ -717,6 +718,10 @@ class Project < ApplicationRecord
     Feature.enabled?(:project_daily_statistics, self, default_enabled: true)
   end
 
+  def unlink_forks_upon_visibility_decrease_enabled?
+    Feature.enabled?(:unlink_fork_network_upon_visibility_decrease, self)
+  end
+
   def empty_repo?
     repository.empty?
   end
@@ -1535,6 +1540,7 @@ class Project < ApplicationRecord
 
   # update visibility_level of forks
   def update_forks_visibility_level
+    return if unlink_forks_upon_visibility_decrease_enabled?
     return unless visibility_level < visibility_level_before_last_save
 
     forks.each do |forked_project|

app/services/projects/destroy_service.rb

@@ -31,13 +31,6 @@ module Projects
 
       Projects::UnlinkForkService.new(project, current_user).execute
 
-      # The project is not necessarily a fork, so update the fork network originating
-      # from this project
-      if fork_network = project.root_of_fork_network
-        fork_network.update(root_project: nil,
-                            deleted_root_project_name: project.full_name)
-      end
-
       attempt_destroy_transaction(project)
 
       system_hook_service.execute_hooks_for(project, :destroy)

app/services/projects/overwrite_project_service.rb

@@ -7,7 +7,9 @@ module Projects
 
       Project.transaction do
         move_before_destroy_relationships(source_project)
-        destroy_old_project(source_project)
+        # Reset is required in order to get the proper
+        # uncached fork network method calls value.
+        destroy_old_project(source_project.reset)
         rename_project(source_project.name, source_project.path)
 
         @project

app/services/projects/unlink_fork_service.rb

@@ -2,34 +2,67 @@
 
 module Projects
   class UnlinkForkService < BaseService
-    # rubocop: disable CodeReuse/ActiveRecord
+    # If a fork is given, it:
+    #
+    # - Saves LFS objects to the root project
+    # - Close existing MRs coming from it
+    # - Is removed from the fork network
+    #
+    # If a root of fork(s) is given, it does the same,
+    # but not updating LFS objects (there'll be no related root to cache it).
     def execute
-      return unless @project.forked?
+      fork_network = @project.fork_network
 
-      if fork_source = @project.fork_source
-        fork_source.lfs_objects.find_each do |lfs_object|
-          lfs_object.projects << @project unless lfs_object.projects.include?(@project)
-        end
+      return unless fork_network
 
-        refresh_forks_count(fork_source)
-      end
+      save_lfs_objects
 
-      merge_requests = @project.fork_network
+      merge_requests = fork_network
                          .merge_requests
                          .opened
-                         .where.not(target_project: @project)
-                         .from_project(@project)
+                         .from_and_to_forks(@project)
 
-      merge_requests.each do |mr|
+      merge_requests.find_each do |mr|
         ::MergeRequests::CloseService.new(@project, @current_user).execute(mr)
       end
 
+      Project.transaction do
+        # Get out of the fork network as a member and
+        # remove references from all its direct forks.
         @project.fork_network_member.destroy
+        @project.forked_to_members.update_all(forked_from_project_id: nil)
+
+        # The project is not necessarily a fork, so update the fork network originating
+        # from this project
+        if fork_network = @project.root_of_fork_network
+          fork_network.update(root_project: nil, deleted_root_project_name: @project.full_name)
+        end
+      end
+
+      # When the project getting out of the network is a node with parent
+      # and children, both the parent and the node needs a cache refresh.
+      [@project.forked_from_project, @project].compact.each do |project|
+        refresh_forks_count(project)
+      end
     end
-    # rubocop: enable CodeReuse/ActiveRecord
+
+    private
 
     def refresh_forks_count(project)
       Projects::ForksCountService.new(project).refresh_cache
     end
+
+    def save_lfs_objects
+      return unless @project.forked?
+
+      lfs_storage_project = @project.lfs_storage_project
+
+      return unless lfs_storage_project
+      return if lfs_storage_project == @project # that project is being unlinked
+
+      lfs_storage_project.lfs_objects.find_each do |lfs_object|
+        lfs_object.projects << @project unless lfs_object.projects.include?(@project)
+      end
+    end
   end
 end

app/services/projects/update_service.rb

@@ -65,7 +65,7 @@ module Projects
       )
       project_changed_feature_keys = project.project_feature.previous_changes.keys
 
-      if project.previous_changes.include?(:visibility_level) && project.private?
+      if project.visibility_level_previous_changes && project.private?
         # don't enqueue immediately to prevent todos removal in case of a mistake
         TodosDestroyer::ConfidentialIssueWorker.perform_in(Todo::WAIT_FOR_DELETE, nil, project.id)
         TodosDestroyer::ProjectPrivateWorker.perform_in(Todo::WAIT_FOR_DELETE, project.id)
@@ -79,6 +79,11 @@ module Projects
         system_hook_service.execute_hooks_for(project, :update)
       end
 
+      if project.visibility_level_decreased? && project.unlink_forks_upon_visibility_decrease_enabled?
+        # It's a system-bounded operation, so no extra authorization check is required.
+        Projects::UnlinkForkService.new(project, current_user).execute
+      end
+
       update_pages_config if changing_pages_related_config?
     end
 

changelogs/unreleased/osw-delete-fork-relation-upon-visibility-change.yml

+---
+title: Adjust fork network relations upon project visibility change
+merge_request: 20466
+author:
+type: added

ee/app/controllers/ee/projects/merge_requests/application_controller.rb

@@ -62,7 +62,7 @@ module EE
           target_project = if @merge_request # rubocop:disable Gitlab/ModuleWithInstanceVariables
                              @merge_request.target_project # rubocop:disable Gitlab/ModuleWithInstanceVariables
                            elsif project.forked? && project.id.to_s != mr_params[:target_project_id]
-                             project.forked_from_project
+                             project.fork_network_projects.find(mr_params[:target_project_id])
                            else
                              project
                            end

lib/gitlab/visibility_level.rb

@@ -115,6 +115,18 @@ module Gitlab
       end
     end
 
+    def visibility_level_decreased?
+      return false unless visibility_level_previous_changes
+
+      before, after = visibility_level_previous_changes
+
+      before && after && after < before
+    end
+
+    def visibility_level_previous_changes
+      previous_changes[:visibility_level]
+    end
+
     def private?
       visibility_level_value == PRIVATE
     end

spec/lib/gitlab/import_export/all_models.yml

@@ -365,6 +365,7 @@ project:
 - root_of_fork_network
 - fork_network_member
 - fork_network
+- fork_network_projects
 - custom_attributes
 - lfs_file_locks
 - project_badges

spec/lib/gitlab/visibility_level_spec.rb

@@ -95,4 +95,28 @@ describe Gitlab::VisibilityLevel do
       expect(described_class.valid_level?(described_class::PUBLIC)).to be_truthy
     end
   end
+
+  describe '#visibility_level_decreased?' do
+    let(:project) { create(:project, :internal) }
+
+    context 'when visibility level decreases' do
+      before do
+        project.update!(visibility_level: described_class::PRIVATE)
+      end
+
+      it 'returns true' do
+        expect(project.visibility_level_decreased?).to be(true)
+      end
+    end
+
+    context 'when visibility level does not decrease' do
+      before do
+        project.update!(visibility_level: described_class::PUBLIC)
+      end
+
+      it 'returns false' do
+        expect(project.visibility_level_decreased?).to be(false)
+      end
+    end
+  end
 end

spec/models/merge_request_spec.rb

@@ -33,6 +33,21 @@ describe MergeRequest do
     end
   end
 
+  describe '.from_and_to_forks' do
+    it 'returns only MRs from and to forks (with no internal MRs)' do
+      project = create(:project)
+      fork = fork_project(project)
+      fork_2 = fork_project(project)
+      mr_from_fork = create(:merge_request, source_project: fork, target_project: project)
+      mr_to_fork = create(:merge_request, source_project: project, target_project: fork)
+
+      create(:merge_request, source_project: fork, target_project: fork_2)
+      create(:merge_request, source_project: project, target_project: project)
+
+      expect(described_class.from_and_to_forks(project)).to contain_exactly(mr_from_fork, mr_to_fork)
+    end
+  end
+
   describe 'locking' do
     using RSpec::Parameterized::TableSyntax
 

spec/services/projects/destroy_service_spec.rb

@@ -296,9 +296,12 @@ describe Projects::DestroyService do
   end
 
   context 'as the root of a fork network' do
-    let!(:fork_network) { create(:fork_network, root_project: project) }
+    let!(:fork_1) { fork_project(project, user) }
+    let!(:fork_2) { fork_project(project, user) }
 
     it 'updates the fork network with the project name' do
+      fork_network = project.fork_network
+
       destroy_project(project, user)
 
       fork_network.reload

spec/services/projects/unlink_fork_service_spec.rb

@@ -2,13 +2,13 @@
 
 require 'spec_helper'
 
-describe Projects::UnlinkForkService do
+describe Projects::UnlinkForkService, :use_clean_rails_memory_store_caching do
   include ProjectForksHelper
 
   subject { described_class.new(forked_project, user) }
 
   let(:project) { create(:project, :public) }
-  let(:forked_project) { fork_project(project, user) }
+  let!(:forked_project) { fork_project(project, user) }
   let(:user) { create(:user) }
 
   context 'with opened merge request on the source project' do
@@ -86,4 +86,169 @@ describe Projects::UnlinkForkService do
       expect { subject.execute }.not_to raise_error
     end
   end
+
+  context 'when given project is a source of forks' do
+    let!(:forked_project_2) { fork_project(project, user) }
+    let!(:fork_of_fork) { fork_project(forked_project, user) }
+
+    subject { described_class.new(project, user) }
+
+    context 'with opened merge requests from fork back to root project' do
+      let!(:merge_request) { create(:merge_request, source_project: project, target_project: forked_project) }
+      let!(:merge_request2) { create(:merge_request, source_project: project, target_project: fork_project(project)) }
+      let!(:merge_request_in_fork) { create(:merge_request, source_project: forked_project, target_project: forked_project) }
+
+      let(:mr_close_service) { MergeRequests::CloseService.new(project, user) }
+
+      before do
+        allow(MergeRequests::CloseService).to receive(:new)
+                                                .with(project, user)
+                                                .and_return(mr_close_service)
+      end
+
+      it 'closes all pending merge requests' do
+        expect(mr_close_service).to receive(:execute).with(merge_request)
+        expect(mr_close_service).to receive(:execute).with(merge_request2)
+
+        subject.execute
+      end
+
+      it 'does not close merge requests that do not come from the project being unlinked' do
+        expect(mr_close_service).not_to receive(:execute).with(merge_request_in_fork)
+
+        subject.execute
+      end
+    end
+
+    it 'removes its link to the fork network and updates direct network members' do
+      expect(project.fork_network_member).to be_present
+      expect(project.fork_network).to be_present
+      expect(project.forked_to_members.count).to eq(2)
+      expect(forked_project.forked_to_members.count).to eq(1)
+      expect(fork_of_fork.forked_to_members.count).to eq(0)
+
+      subject.execute
+
+      project.reload
+      forked_project.reload
+      fork_of_fork.reload
+
+      expect(project.fork_network_member).to be_nil
+      expect(project.fork_network).to be_nil
+      expect(forked_project.fork_network).to have_attributes(root_project_id: nil,
+                                                             deleted_root_project_name: project.full_name)
+      expect(project.forked_to_members.count).to eq(0)
+      expect(forked_project.forked_to_members.count).to eq(1)
+      expect(fork_of_fork.forked_to_members.count).to eq(0)
+    end
+
+    it 'refreshes the forks count cache of the given project' do
+      expect(project.forks_count).to eq(2)
+
+      subject.execute
+
+      expect(project.forks_count).to be_zero
+    end
+
+    context 'when given project is a fork of an unlinked parent' do
+      let!(:fork_of_fork) { fork_project(forked_project, user) }
+      let(:lfs_object) { create(:lfs_object) }
+
+      before do
+        lfs_object.projects << project
+      end
+
+      it 'saves lfs objects to the root project' do
+        # Remove parent from network
+        described_class.new(forked_project, user).execute
+
+        described_class.new(fork_of_fork, user).execute
+
+        expect(lfs_object.projects).to include(fork_of_fork)
+      end
+    end
+
+    context 'and is node with a parent' do
+      subject { described_class.new(forked_project, user) }
+
+      context 'with opened merge requests from and to given project' do
+        let!(:mr_from_parent) { create(:merge_request, source_project: project, target_project: forked_project) }
+        let!(:mr_to_parent) { create(:merge_request, source_project: forked_project, target_project: project) }
+        let!(:mr_to_child) { create(:merge_request, source_project: forked_project, target_project: fork_of_fork) }
+        let!(:mr_from_child) { create(:merge_request, source_project: fork_of_fork, target_project: forked_project) }
+        let!(:merge_request_in_fork) { create(:merge_request, source_project: forked_project, target_project: forked_project) }
+
+        let(:mr_close_service) { MergeRequests::CloseService.new(forked_project, user) }
+
+        before do
+          allow(MergeRequests::CloseService).to receive(:new)
+            .with(forked_project, user)
+            .and_return(mr_close_service)
+        end
+
+        it 'close all pending merge requests' do
+          merge_requests = [mr_from_parent, mr_to_parent, mr_from_child, mr_to_child]
+
+          merge_requests.each do |mr|
+            expect(mr_close_service).to receive(:execute).with(mr).and_call_original
+          end
+
+          subject.execute
+
+          merge_requests = MergeRequest.where(id: merge_requests)
+
+          expect(merge_requests).to all(have_attributes(state: 'closed'))
+        end
+
+        it 'does not close merge requests which do not come from the project being unlinked' do
+          expect(mr_close_service).not_to receive(:execute).with(merge_request_in_fork)
+
+          subject.execute
+        end
+      end
+
+      it 'refreshes the forks count cache of the parent and the given project' do
+        expect(project.forks_count).to eq(2)
+        expect(forked_project.forks_count).to eq(1)
+
+        subject.execute
+
+        expect(project.forks_count).to eq(1)
+        expect(forked_project.forks_count).to eq(0)
+      end
+
+      it 'removes its link to the fork network and updates direct network members' do
+        expect(project.fork_network).to be_present
+        expect(forked_project.fork_network).to be_present
+        expect(fork_of_fork.fork_network).to be_present
+
+        expect(project.forked_to_members.count).to eq(2)
+        expect(forked_project.forked_to_members.count).to eq(1)
+        expect(fork_of_fork.forked_to_members.count).to eq(0)
+
+        subject.execute
+        project.reload
+        forked_project.reload
+        fork_of_fork.reload
+
+        expect(project.fork_network).to be_present
+        expect(forked_project.fork_network).to be_nil
+        expect(fork_of_fork.fork_network).to be_present
+
+        expect(project.forked_to_members.count).to eq(1) # 1 child is gone
+        expect(forked_project.forked_to_members.count).to eq(0)
+        expect(fork_of_fork.forked_to_members.count).to eq(0)
+      end
+    end
+  end
+
+  context 'when given project is not part of a fork network' do
+    let!(:project_without_forks) { create(:project, :public) }
+
+    subject { described_class.new(project_without_forks, user) }
+
+    it 'does not raise errors' do
+      expect { subject.execute }.not_to raise_error
+    end
+  end
 end

spec/services/projects/update_service_spec.rb

@@ -16,7 +16,14 @@ describe Projects::UpdateService do
     let(:admin) { create(:admin) }
 
     context 'when changing visibility level' do
-      context 'when visibility_level is INTERNAL' do
+      def expect_to_call_unlink_fork_service
+        service = Projects::UnlinkForkService.new(project, user)
+
+        expect(Projects::UnlinkForkService).to receive(:new).with(project, user).and_return(service)
+        expect(service).to receive(:execute).and_call_original
+      end
+
+      context 'when visibility_level changes to INTERNAL' do
         it 'updates the project to internal' do
           expect(TodosDestroyer::ProjectPrivateWorker).not_to receive(:perform_in)
 
@@ -25,9 +32,21 @@ describe Projects::UpdateService do
           expect(result).to eq({ status: :success })
           expect(project).to be_internal
         end
+
+        context 'and project is PUBLIC' do
+          before do
+            project.update!(visibility_level: Gitlab::VisibilityLevel::PUBLIC)
           end
 
-      context 'when visibility_level is PUBLIC' do
+          it 'unlinks project from fork network' do
+            expect_to_call_unlink_fork_service
+
+            update_project(project, user, visibility_level: Gitlab::VisibilityLevel::INTERNAL)
+          end
+        end
+      end
+
+      context 'when visibility_level changes to PUBLIC' do
         it 'updates the project to public' do
           expect(TodosDestroyer::ProjectPrivateWorker).not_to receive(:perform_in)
 
@@ -36,9 +55,17 @@ describe Projects::UpdateService do
           expect(result).to eq({ status: :success })
           expect(project).to be_public
         end
+
+        context 'and project is PRIVATE' do
+          it 'does not unlink project from fork network' do
+            expect(Projects::UnlinkForkService).not_to receive(:new)
+
+            update_project(project, user, visibility_level: Gitlab::VisibilityLevel::PUBLIC)
+          end
+        end
       end
 
-      context 'when visibility_level is PRIVATE' do
+      context 'when visibility_level changes to PRIVATE' do
         before do
           project.update!(visibility_level: Gitlab::VisibilityLevel::PUBLIC)
         end
@@ -52,6 +79,30 @@ describe Projects::UpdateService do
           expect(result).to eq({ status: :success })
           expect(project).to be_private
         end
+
+        context 'and project is PUBLIC' do
+          before do
+            project.update!(visibility_level: Gitlab::VisibilityLevel::PUBLIC)
+          end
+
+          it 'unlinks project from fork network' do
+            expect_to_call_unlink_fork_service
+
+            update_project(project, user, visibility_level: Gitlab::VisibilityLevel::PRIVATE)
+          end
+        end
+
+        context 'and project is INTERNAL' do
+          before do
+            project.update!(visibility_level: Gitlab::VisibilityLevel::INTERNAL)
+          end
+
+          it 'unlinks project from fork network' do
+            expect_to_call_unlink_fork_service
+
+            update_project(project, user, visibility_level: Gitlab::VisibilityLevel::PRIVATE)
+          end
+        end
       end
 
       context 'when visibility levels are restricted to PUBLIC only' do
@@ -107,6 +158,11 @@ describe Projects::UpdateService do
       let(:project) { create(:project, :internal) }
       let(:forked_project) { fork_project(project) }
 
+      context 'and unlink forks feature flag is off' do
+        before do
+          stub_feature_flags(unlink_fork_network_upon_visibility_decrease: false)
+        end
+
         it 'updates forks visibility level when parent set to more restrictive' do
           opts = { visibility_level: Gitlab::VisibilityLevel::PRIVATE }
 
@@ -132,6 +188,21 @@ describe Projects::UpdateService do
         end
       end
 
+      context 'and unlink forks feature flag is on' do
+        it 'does not change visibility of forks' do
+          opts = { visibility_level: Gitlab::VisibilityLevel::PRIVATE }
+
+          expect(project).to be_internal
+          expect(forked_project).to be_internal
+
+          expect(update_project(project, admin, opts)).to eq({ status: :success })
+
+          expect(project).to be_private
+          expect(forked_project.reload).to be_internal
+        end
+      end
+    end
+
     context 'when updating a default branch' do
       let(:project) { create(:project, :repository) }