Log invalid realtions build during Gitlab Project/Group import

Some imports are failing without clear reasons. To bring some light on
invalid relations will be logged. With these logs in place we'll be able
to check what validations need to be disabled for the import process.

Related to: https://gitlab.com/gitlab-org/gitlab/-/issues/285107

lib/gitlab/import_export/relation_tree_restorer.rb

@@ -71,7 +71,7 @@ module Gitlab
       end
 
       def process_relation_item!(relation_key, relation_definition, relation_index, data_hash)
-        relation_object = build_relation(relation_key, relation_definition, data_hash)
+        relation_object = build_relation(relation_key, relation_definition, relation_index, data_hash)
         return unless relation_object
         return if importable_class == ::Project && group_model?(relation_object)
 
@@ -139,23 +139,35 @@ module Gitlab
         end
       end
 
-      def build_relations(relation_key, relation_definition, data_hashes)
+      def build_relations(relation_key, relation_definition, relation_index, data_hashes)
         data_hashes
-          .map { |data_hash| build_relation(relation_key, relation_definition, data_hash) }
+          .map { |data_hash| build_relation(relation_key, relation_definition, relation_index, data_hash) }
           .tap { |entries| entries.compact! }
       end
 
-      def build_relation(relation_key, relation_definition, data_hash)
+      def build_relation(relation_key, relation_definition, relation_index, data_hash)
         # TODO: This is hack to not create relation for the author
         # Rather make `RelationFactory#set_note_author` to take care of that
         return data_hash if relation_key == 'author' || already_restored?(data_hash)
 
         # create relation objects recursively for all sub-objects
         relation_definition.each do |sub_relation_key, sub_relation_definition|
-          transform_sub_relations!(data_hash, sub_relation_key, sub_relation_definition)
+          transform_sub_relations!(data_hash, sub_relation_key, sub_relation_definition, relation_index)
         end
 
-        @relation_factory.create(relation_factory_params(relation_key, data_hash))
+        relation = @relation_factory.create(relation_factory_params(relation_key, data_hash))
+
+        if relation && !relation.valid?
+          @shared.logger.warn(
+            message: "[Project/Group Import] Invalid object relation built",
+            relation_key: relation_key,
+            relation_index: relation_index,
+            relation_class: relation.class.name,
+            error_messages: relation.errors.full_messages.join(". ")
+          )
+        end
+
+        relation
       end
 
       # Since we update the data hash in place as we restore relation items,
@@ -165,7 +177,7 @@ module Gitlab
         !relation_item.is_a?(Hash)
       end
 
-      def transform_sub_relations!(data_hash, sub_relation_key, sub_relation_definition)
+      def transform_sub_relations!(data_hash, sub_relation_key, sub_relation_definition, relation_index)
         sub_data_hash = data_hash[sub_relation_key]
         return unless sub_data_hash
 
@@ -176,11 +188,13 @@ module Gitlab
             build_relations(
               sub_relation_key,
               sub_relation_definition,
+              relation_index,
               sub_data_hash).presence
           else
             build_relation(
               sub_relation_key,
               sub_relation_definition,
+              relation_index,
               sub_data_hash)
           end
 

spec/fixtures/lib/gitlab/import_export/project_with_invalid_relations/tree/project.json

+{"description":"Nisi et repellendus ut enim quo accusamus vel magnam.","import_type":"gitlab_project","creator_id":2147483547,"visibility_level":10,"archived":false,"hooks":[]}

spec/fixtures/lib/gitlab/import_export/project_with_invalid_relations/tree/project/labels.ndjson

+{"id":2,"title":"","color":"#428bca","project_id":8,"created_at":"2016-07-22T08:55:44.161Z","updated_at":"2016-07-22T08:55:44.161Z","template":false,"description":"","type":"","priorities":[]}

spec/lib/gitlab/import_export/relation_tree_restorer_spec.rb

@@ -113,12 +113,31 @@ RSpec.describe Gitlab::ImportExport::RelationTreeRestorer do
 
         include_examples 'logging of relations creation'
       end
+    end
+
+    context 'using ndjson reader' do
+      let(:path) { 'spec/fixtures/lib/gitlab/import_export/complex/tree' }
+      let(:relation_reader) { Gitlab::ImportExport::JSON::NdjsonReader.new(path) }
+
+      it_behaves_like 'import project successfully'
+    end
 
-      context 'using ndjson reader' do
-        let(:path) { 'spec/fixtures/lib/gitlab/import_export/complex/tree' }
-        let(:relation_reader) { Gitlab::ImportExport::JSON::NdjsonReader.new(path) }
+    context 'with invalid relations' do
+      let(:path) { 'spec/fixtures/lib/gitlab/import_export/project_with_invalid_relations/tree' }
+      let(:relation_reader) { Gitlab::ImportExport::JSON::NdjsonReader.new(path) }
 
-        it_behaves_like 'import project successfully'
+      it 'logs the invalid relation and its errors' do
+        expect(relation_tree_restorer.shared.logger)
+          .to receive(:warn)
+          .with(
+            error_messages: "Title can't be blank. Title is invalid",
+            message: '[Project/Group Import] Invalid object relation built',
+            relation_class: 'ProjectLabel',
+            relation_index: 0,
+            relation_key: 'labels'
+          ).once
+
+        relation_tree_restorer.restore
       end
     end
   end

spec/services/groups/import_export/import_service_spec.rb

@@ -110,6 +110,7 @@ RSpec.describe Groups::ImportExport::ImportService do
         allow(Gitlab::Import::Logger).to receive(:build).and_return(import_logger)
         allow(import_logger).to receive(:error)
         allow(import_logger).to receive(:info)
+        allow(import_logger).to receive(:warn)
         allow(FileUtils).to receive(:rm_rf).and_call_original
       end
 
@@ -220,6 +221,7 @@ RSpec.describe Groups::ImportExport::ImportService do
 
         allow(Gitlab::Import::Logger).to receive(:build).and_return(import_logger)
         allow(import_logger).to receive(:error)
+        allow(import_logger).to receive(:warn)
         allow(import_logger).to receive(:info)
         allow(FileUtils).to receive(:rm_rf).and_call_original
       end

spec/support/import_export/common_util.rb

@@ -70,9 +70,12 @@ module ImportExport
       )
     end
 
-    def get_shared_env(path:)
+    def get_shared_env(path:, logger: nil)
+      logger ||= double(info: true, warn: true, error: true)
+
       instance_double(Gitlab::ImportExport::Shared).tap do |shared|
         allow(shared).to receive(:export_path).and_return(path)
+        allow(shared).to receive(:logger).and_return(logger)
       end
     end