archive: update unarchive script to handle git repositories

app/models/group.rb

@@ -86,6 +86,8 @@ def repo_path
   # Git repos are stored on disk but not other types of repo (ie. memory)
   if Settings.repository.type == 'git'
     def _file_location
+      return if self.course.nil?
+
       Repository.get_class.respond_to?(:bare_path) ? Repository.get_class.bare_path(repo_path) : repo_path
     end
   end

lib/archive_tools/course_archiver.rb

@@ -294,9 +294,11 @@ def unarchive(archive_file, tmp_db_url: nil)
             record = klass.new(attributes)
 
             # Get the old file location before updating foreign keys so that file locations dependant on
-            # associated records are calculated correctly.
+            # foreign key values are calculated correctly. This works for files whose location is dependant
+            # on foreign keys (eg: starter file group files), but not for files whose location is dependant
+            # on associated records themselves (eg: group repositories); these are discovered after the new
+            # record is created in the database.
             old_file_location = nil
-            new_file_location = nil
             if record.respond_to? :_file_location
               old_file_location = temporary_file_storage(data_dir) { record._file_location }
             end
@@ -315,6 +317,14 @@ def unarchive(archive_file, tmp_db_url: nil)
               record.assign_attributes(k => new_ids[associated_class.table_name][v.to_s])
             end
 
+            if record.respond_to?(:_file_location) && !File.exist?(old_file_location.to_s)
+              # The file may not exist if the location is dependant on the existence of an
+              # associated object in the database (eg: group repositories' locations depend on
+              # the course name). That object may not have existed yet the last time that
+              # old_file_location was calculated
+              old_file_location = temporary_file_storage(data_dir) { record._file_location }
+            end
+
             # nullify the id so that it can be assigned a new one.
             # insert is used so that callbacks and validations are not run
             result = klass.insert(record.attributes.except('id'),

spec/lib/archive_tools/course_archiver_spec.rb

@@ -2,6 +2,9 @@
 
 describe ArchiveTools::CourseArchiver do
   include ArchiveTools::CourseArchiver
+  let(:repo_type) { 'mem' }
+  before { allow(Settings.repository).to receive(:type).and_return(repo_type) }
+
   let(:full_course) do
     course = create :course
     create :assignment_with_criteria_and_test_results, course: course
@@ -51,7 +54,6 @@
         expect(archived_course_id).to eq course.id.to_s
       end
       it 'contains the expected db files' do
-        subject
         Rails.application.eager_load!
         files = ApplicationRecord.descendants
                                  .reject { |klass| ids_associated_to_course(course, klass).empty? }
@@ -60,7 +62,6 @@
         expect(archived_db_data.map { |f| File.basename(f) }).to contain_exactly(*files)
       end
       it 'contains the expected data files' do
-        subject
         Rails.application.eager_load!
         allow(Settings).to receive(:file_storage).and_return Config::Options.new(default_root_path: archived_file_loc)
         files = ApplicationRecord.descendants
@@ -78,6 +79,11 @@
     context 'a full course' do
       let(:course) { full_course }
       it_behaves_like 'archive course'
+      context 'with git repositories', :keep_memory_repos do
+        let(:repo_type) { 'git' }
+        after { FileUtils.rm_r(Dir.glob(File.join(Repository.root_dir, '*'))) }
+        it_behaves_like 'archive course'
+      end
     end
     context 'when other courses exist' do
       let(:course) { create :course }
@@ -169,6 +175,13 @@
     context 'using a full valid archive file' do
       it_behaves_like 'unarchive course'
       it_behaves_like 'cleanup after'
+      context 'with git repositories', :keep_memory_repos do
+        let(:archive_file) { Rails.root.join('spec/fixtures/files/unarchive/good_full_git.tar.gz') }
+        let(:repo_type) { 'git' }
+        after { FileUtils.rm_r(Dir.glob(File.join(Repository.root_dir, '*'))) }
+        it_behaves_like 'unarchive course'
+        it_behaves_like 'cleanup after'
+      end
     end
     context 'using an archive file with missing data' do
       before do