Extract code from Issues::MoveServicece-3777-promote-to-epic

Extract code to make it easier reusable
- introduce AttributesRewriter and ContentRewriter
  - support group entites when rewriting content
- make Uploader copy_to working for Namespaces

5 files changed, 219 insertions, 131 deletions

diff --git a/app/services/issuable/clone/attributes_rewriter.rb b/app/services/issuable/clone/attributes_rewriter.rb
new file mode 100644
index 00000000000..0300cc0d8d3
--- /dev/null
+++ b/app/services/issuable/clone/attributes_rewriter.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+module Issuable
+  module Clone
+    class AttributesRewriter < ::Issuable::Clone::BaseService
+      def initialize(current_user, original_entity, new_entity)
+        @current_user = current_user
+        @original_entity = original_entity
+        @new_entity = new_entity
+      end
+
+      def execute
+        new_entity.update(milestone: cloneable_milestone, labels: cloneable_labels)
+        copy_resource_label_events
+      end
+
+      private
+
+      def cloneable_milestone
+        title = original_entity.milestone&.title
+        return unless title
+
+        params = { title: title, project_ids: new_entity.project&.id, group_ids: group&.id }
+
+        milestones = MilestonesFinder.new(params).execute
+        milestones.first
+      end
+
+      def cloneable_labels
+        params = {
+          project_id: new_entity.project&.id,
+          group_id: group&.id,
+          title: original_entity.labels.select(:title),
+          include_ancestor_groups: true
+        }
+
+        params[:only_group_labels] = true if new_parent.is_a?(Group)
+
+        LabelsFinder.new(current_user, params).execute
+      end
+
+      def copy_resource_label_events
+        original_entity.resource_label_events.find_in_batches do |batch|
+          events = batch.map do |event|
+            entity_key = new_entity.is_a?(Issue) ? 'issue_id' : 'epic_id'
+            # rubocop: disable CodeReuse/ActiveRecord
+            event.attributes
+              .except('id', 'reference', 'reference_html')
+              .merge(entity_key => new_entity.id, 'action' => ResourceLabelEvent.actions[event.action])
+            # rubocop: enable CodeReuse/ActiveRecord
+          end
+
+          Gitlab::Database.bulk_insert(ResourceLabelEvent.table_name, events)
+        end
+      end
+
+      def entity_key
+        new_entity.class.name.parameterize('_').foreign_key
+      end
+    end
+  end
+end
diff --git a/app/services/issuable/clone/base_service.rb b/app/services/issuable/clone/base_service.rb
new file mode 100644
index 00000000000..42dd9c666f5
--- /dev/null
+++ b/app/services/issuable/clone/base_service.rb
@@ -0,0 +1,60 @@
+# frozen_string_literal: true
+
+module Issuable
+  module Clone
+    class BaseService < IssuableBaseService
+      attr_reader :original_entity, :new_entity
+
+      alias_method :old_project, :project
+
+      def execute(original_entity, new_project = nil)
+        @original_entity = original_entity
+
+        # Using transaction because of a high resources footprint
+        # on rewriting notes (unfolding references)
+        #
+        ActiveRecord::Base.transaction do
+          @new_entity = create_new_entity
+
+          update_new_entity
+          update_old_entity
+          create_notes
+        end
+      end
+
+      private
+
+      def update_new_entity
+        rewriters = [ContentRewriter, AttributesRewriter]
+
+        rewriters.each do |rewriter|
+          rewriter.new(current_user, original_entity, new_entity).execute
+        end
+      end
+
+      def update_old_entity
+        close_issue
+      end
+
+      def create_notes
+        add_note_from
+        add_note_to
+      end
+
+      def close_issue
+        close_service = Issues::CloseService.new(old_project, current_user)
+        close_service.execute(original_entity, notifications: false, system_note: false)
+      end
+
+      def new_parent
+        new_entity.project ? new_entity.project : new_entity.group
+      end
+
+      def group
+        if new_entity.project&.group && current_user.can?(:read_group, new_entity.project.group)
+          new_entity.project.group
+        end
+      end
+    end
+  end
+end
diff --git a/app/services/issuable/clone/content_rewriter.rb b/app/services/issuable/clone/content_rewriter.rb
new file mode 100644
index 00000000000..e1e0b75085d
--- /dev/null
+++ b/app/services/issuable/clone/content_rewriter.rb
@@ -0,0 +1,65 @@
+# frozen_string_literal: true
+
+module Issuable
+  module Clone
+    class ContentRewriter < ::Issuable::Clone::BaseService
+      def initialize(current_user, original_entity, new_entity)
+        @current_user = current_user
+        @original_entity = original_entity
+        @new_entity = new_entity
+        @project = original_entity.project
+      end
+
+      def execute
+        rewrite_description
+        rewrite_award_emoji(original_entity, new_entity)
+        rewrite_notes
+      end
+
+      private
+
+      def rewrite_description
+        new_entity.update(description: rewrite_content(original_entity.description))
+      end
+
+      def rewrite_notes
+        original_entity.notes_with_associations.find_each do |note|
+          new_note = note.dup
+          new_params = {
+            project: new_entity.project, noteable: new_entity,
+            note: rewrite_content(new_note.note),
+            created_at: note.created_at,
+            updated_at: note.updated_at
+          }
+
+          if note.system_note_metadata
+            new_params[:system_note_metadata] = note.system_note_metadata.dup
+          end
+
+          new_note.update(new_params)
+
+          rewrite_award_emoji(note, new_note)
+        end
+      end
+
+      def rewrite_content(content)
+        return unless content
+
+        rewriters = [Gitlab::Gfm::ReferenceRewriter, Gitlab::Gfm::UploadsRewriter]
+
+        rewriters.inject(content) do |text, klass|
+          rewriter = klass.new(text, old_project, current_user)
+          rewriter.rewrite(new_parent)
+        end
+      end
+
+      def rewrite_award_emoji(old_awardable, new_awardable)
+        old_awardable.award_emoji.each do |award|
+          new_award = award.dup
+          new_award.awardable = new_awardable
+          new_award.save
+        end
+      end
+    end
+  end
+end
diff --git a/app/services/issues/move_service.rb b/app/services/issues/move_service.rb
index d2bdba1e627..41b6a96b005 100644
--- a/app/services/issues/move_service.rb
+++ b/app/services/issues/move_service.rb
@@ -1,165 +1,66 @@
 # frozen_string_literal: true
 
 module Issues
-  class MoveService < Issues::BaseService
+  class MoveService < Issuable::Clone::BaseService
     MoveError = Class.new(StandardError)
 
-    def execute(issue, new_project)
-      @old_issue = issue
-      @old_project = @project
-      @new_project = new_project
+    def execute(issue, target_project)
+      @target_project = target_project
 
-      unless issue.can_move?(current_user, new_project)
+      unless issue.can_move?(current_user, @target_project)
         raise MoveError, 'Cannot move issue due to insufficient permissions!'
       end
 
-      if @project == new_project
+      if @project == @target_project
         raise MoveError, 'Cannot move issue to project it originates from!'
       end
 
-      # Using transaction because of a high resources footprint
-      # on rewriting notes (unfolding references)
-      #
-      ActiveRecord::Base.transaction do
-        @new_issue = create_new_issue
-
-        update_new_issue
-        update_old_issue
-      end
+      super
 
       notify_participants
 
-      @new_issue
+      new_entity
     end
 
     private
 
-    def update_new_issue
-      rewrite_notes
-      copy_resource_label_events
-      rewrite_issue_award_emoji
-      add_note_moved_from
-    end
+    def update_old_entity
+      super
 
-    def update_old_issue
-      add_note_moved_to
-      close_issue
       mark_as_moved
     end
 
-    def create_new_issue
-      new_params = { id: nil, iid: nil, label_ids: cloneable_label_ids,
-                     milestone_id: cloneable_milestone_id,
-                     project: @new_project, author: @old_issue.author,
-                     description: rewrite_content(@old_issue.description),
-                     assignee_ids: @old_issue.assignee_ids }
-
-      new_params = @old_issue.serializable_hash.symbolize_keys.merge(new_params)
-      CreateService.new(@new_project, @current_user, new_params).execute
-    end
-
-    # rubocop: disable CodeReuse/ActiveRecord
-    def cloneable_label_ids
-      params = {
-        project_id: @new_project.id,
-        title: @old_issue.labels.pluck(:title),
-        include_ancestor_groups: true
-      }
+    def create_new_entity
+      new_params = {
+                     id: nil,
+                     iid: nil,
+                     project: @target_project,
+                     author: original_entity.author,
+                     assignee_ids: original_entity.assignee_ids
+                   }
 
-      LabelsFinder.new(current_user, params).execute.pluck(:id)
+      new_params = original_entity.serializable_hash.symbolize_keys.merge(new_params)
+      CreateService.new(@target_project, @current_user, new_params).execute
     end
-    # rubocop: enable CodeReuse/ActiveRecord
-
-    def cloneable_milestone_id
-      title = @old_issue.milestone&.title
-      return unless title
-
-      if @new_project.group && can?(current_user, :read_group, @new_project.group)
-        group_id = @new_project.group.id
-      end
-
-      params =
-        { title: title, project_ids: @new_project.id, group_ids: group_id }
 
-      milestones = MilestonesFinder.new(params).execute
-      milestones.first&.id
-    end
-
-    def rewrite_notes
-      @old_issue.notes_with_associations.find_each do |note|
-        new_note = note.dup
-        new_params = { project: @new_project, noteable: @new_issue,
-                       note: rewrite_content(new_note.note),
-                       created_at: note.created_at,
-                       updated_at: note.updated_at }
-
-        new_note.update(new_params)
-
-        rewrite_award_emoji(note, new_note)
-      end
-    end
-
-    # rubocop: disable CodeReuse/ActiveRecord
-    def copy_resource_label_events
-      @old_issue.resource_label_events.find_in_batches do |batch|
-        events = batch.map do |event|
-          event.attributes
-            .except('id', 'reference', 'reference_html')
-            .merge('issue_id' => @new_issue.id, 'action' => ResourceLabelEvent.actions[event.action])
-        end
-
-        Gitlab::Database.bulk_insert(ResourceLabelEvent.table_name, events)
-      end
-    end
-    # rubocop: enable CodeReuse/ActiveRecord
-
-    def rewrite_issue_award_emoji
-      rewrite_award_emoji(@old_issue, @new_issue)
-    end
-
-    def rewrite_award_emoji(old_awardable, new_awardable)
-      old_awardable.award_emoji.each do |award|
-        new_award = award.dup
-        new_award.awardable = new_awardable
-        new_award.save
-      end
-    end
-
-    def rewrite_content(content)
-      return unless content
-
-      rewriters = [Gitlab::Gfm::ReferenceRewriter,
-                   Gitlab::Gfm::UploadsRewriter]
-
-      rewriters.inject(content) do |text, klass|
-        rewriter = klass.new(text, @old_project, @current_user)
-        rewriter.rewrite(@new_project)
-      end
+    def mark_as_moved
+      original_entity.update(moved_to: new_entity)
     end
 
-    def close_issue
-      close_service = CloseService.new(@old_project, @current_user)
-      close_service.execute(@old_issue, notifications: false, system_note: false)
+    def notify_participants
+      notification_service.async.issue_moved(original_entity, new_entity, @current_user)
     end
 
-    def add_note_moved_from
-      SystemNoteService.noteable_moved(@new_issue, @new_project,
-                                       @old_issue, @current_user,
+    def add_note_from
+      SystemNoteService.noteable_moved(new_entity, @target_project,
+                                       original_entity, current_user,
                                        direction: :from)
     end
 
-    def add_note_moved_to
-      SystemNoteService.noteable_moved(@old_issue, @old_project,
-                                       @new_issue, @current_user,
+    def add_note_to
+      SystemNoteService.noteable_moved(original_entity, old_project,
+                                       new_entity, current_user,
                                        direction: :to)
     end
-
-    def mark_as_moved
-      @old_issue.update(moved_to: @new_issue)
-    end
-
-    def notify_participants
-      notification_service.async.issue_moved(@old_issue, @new_issue, @current_user)
-    end
   end
 end
diff --git a/app/uploaders/file_uploader.rb b/app/uploaders/file_uploader.rb
index ffc1e5f75ca..e90599f2505 100644
--- a/app/uploaders/file_uploader.rb
+++ b/app/uploaders/file_uploader.rb
@@ -149,9 +149,9 @@ class FileUploader < GitlabUploader
 
   # return a new uploader with a file copy on another project
   def self.copy_to(uploader, to_project)
-    moved = uploader.dup.tap do |u|
-      u.model = to_project
-    end
+    moved = self.new(to_project)
+    moved.object_store = uploader.object_store
+    moved.filename = uploader.filename
 
     moved.copy_file(uploader.file)
     moved