Add uploads rewriter and use it when moving issue

app/services/issues/move_service.rb

@@ -43,7 +43,7 @@ module Issues
     def create_new_issue
       new_params = { id: nil, iid: nil, label_ids: [], milestone: nil,
                      project: @new_project, author: @old_issue.author,
-                     description: unfold_references(@old_issue.description) }
+                     description: rewrite_content(@old_issue.description) }
       new_params = @old_issue.serializable_hash.merge(new_params)
       CreateService.new(@new_project, @current_user, new_params).execute
@@ -53,7 +53,7 @@ module Issues
       @old_issue.notes.find_each do |note|
         new_note = note.dup
         new_params = { project: @new_project, noteable: @new_issue,
-                       note: unfold_references(new_note.note),
+                       note: rewrite_content(new_note.note),
                        created_at: note.created_at,
                        updated_at: note.updated_at }
@@ -61,6 +61,29 @@ module Issues
       end
     end
+    def rewrite_content(content)
+      rewrite_uploads(
+        unfold_references(content)
+      )
+    end
+
+    def unfold_references(content)
+      return unless content
+
+      rewriter = Gitlab::Gfm::ReferenceRewriter.new(content, @old_project,
+                                                    @current_user)
+      rewriter.rewrite(@new_project)
+    end
+
+    def rewrite_uploads(content)
+      return unless content
+
+      rewriter = Gitlab::Gfm::UploadsRewriter.new(content, @old_project,
+                                                  @current_user)
+      return content unless rewriter.has_uploads?
+      rewriter.rewrite(@new_project)
+    end
+
     def close_issue
       close_service = CloseService.new(@old_project, @current_user)
       close_service.execute(@old_issue, notifications: false, system_note: false)
@@ -78,20 +101,12 @@ module Issues
                                        direction: :to)
     end
-    def unfold_references(content)
-      return unless content
-
-      rewriter = Gitlab::Gfm::ReferenceRewriter.new(content, @old_project,
-                                                    @current_user)
-      rewriter.rewrite(@new_project)
+    def mark_as_moved
+      @old_issue.update(moved_to: @new_issue)
     end
     def notify_participants
       notification_service.issue_moved(@old_issue, @new_issue, @current_user)
     end
-
-    def mark_as_moved
-      @old_issue.update(moved_to: @new_issue)
-    end
   end
 end

lib/gitlab/gfm/uploads_rewriter.rb

+module Gitlab
+  module Gfm
+    ##
+    # Class that rewrites markdown links for uploads
+    #
+    # Using a pattern defined in `FileUploader` copies files to a new project
+    # and rewrites all links to uploads in ain a given text.
+    #
+    class UploadsRewriter
+      def initialize(text, source_project, _current_user)
+        @text = text
+        @source_project = source_project
+        @pattern = FileUploader::MARKDOWN_PATTERN
+      end
+
+      def rewrite(target_project)
+        return unless @text
+
+        new_uploader = file_uploader(target_project)
+        @text.gsub(@pattern) do |markdown_link|
+          old_file = find_file(@source_project, $~[:secret], $~[:file])
+          return markdown_link unless old_file.exists?
+
+          new_uploader.store!(old_file)
+          new_uploader.to_h[:markdown]
+        end
+      end
+
+      def has_uploads?
+        !(@text =~ @pattern).nil?
+      end
+
+      def files
+        referenced_files = @text.scan(@pattern).map do
+          find_file(@source_project, $~[:secret], $~[:file])
+        end
+
+        referenced_files.compact.select(&:exists?)
+      end
+
+      private
+
+      def find_file(project, secret, file)
+        uploader = file_uploader(project, secret)
+        uploader.retrieve_from_store!(file)
+        uploader.file
+      end
+
+      def file_uploader(*args)
+        uploader = FileUploader.new(*args)
+        uploader.define_singleton_method(:move_to_store) { false }
+        uploader
+      end
+    end
+  end
+end

spec/lib/gitlab/gfm/uploads_rewriter_spec.rb

+require 'spec_helper'
+
+describe Gitlab::Gfm::UploadsRewriter do
+  let(:user) { create(:user) }
+  let(:old_project) { create(:project) }
+  let(:new_project) { create(:project) }
+  let(:rewriter) { described_class.new(text, old_project, user) }
+
+  context 'text contains links to uploads' do
+    let(:path) { Rails.root + 'spec/fixtures/rails_sample.jpg' }
+    let(:file) { fixture_file_upload(path, 'image/jpg') }
+    let(:uploader) { FileUploader.new(old_project) }
+    let!(:store) { uploader.store!(file) } # TODO, see #xxx (carrierwave issue)
+    let(:markdown) { uploader.to_h[:markdown] }
+    let(:text) { "Text and #{markdown}"}
+
+    describe '#rewrite' do
+      let!(:new_text) { rewriter.rewrite(new_project) }
+      let(:new_rewriter) { described_class.new(new_text, new_project, user) }
+      let(:old_file) { rewriter.files.first }
+      let(:new_file) { new_rewriter.files.first }
+
+      it 'rewrites content' do
+        expect(new_text).to_not eq text
+        expect(new_text.length).to eq text.length
+      end
+
+      it 'copies files' do
+        expect(new_file.exists?).to eq true
+        expect(old_file.path).to_not eq new_file.path
+        expect(new_file.path).to include new_project.path_with_namespace
+      end
+
+      it 'does not remove old files' do
+        expect(old_file.exists?).to be true
+      end
+    end
+
+    describe '#has_uploads?' do
+      subject { rewriter.has_uploads? }
+      it { is_expected.to eq true }
+    end
+
+    describe '#files' do
+      subject { rewriter.files }
+      it { is_expected.to be_an(Array) }
+    end
+  end
+end

spec/services/issues/move_service_spec.rb

@@ -160,6 +160,25 @@ describe Issues::MoveService, services: true do
               .to eq "Note with reference to merge request #{old_project.to_reference}!1"
           end
         end
+
+        context 'issue description with uploads' do
+          let(:path) { Rails.root + 'spec/fixtures/rails_sample.jpg' }
+          let(:file) { fixture_file_upload(path, 'image/jpg') }
+          let(:uploader) { FileUploader.new(old_project) }
+          let!(:store) { uploader.store!(file) }
+          let(:markdown) { uploader.to_h[:markdown] }
+          let(:description) { "Text and #{markdown}"}
+
+          include_context 'issue move executed'
+
+          it 'rewrites uploads in description' do
+            expect(new_issue.description).to_not eq description
+            expect(new_issue.description)
+              .to match(/Text and #{FileUploader::MARKDOWN_PATTERN}/)
+          end
+
+          after { uploader.remove! }
+        end
       end
       describe 'rewritting references' do