Add BulkImports NdjsonExtractor & update labels pipeline to use it

  - Use ndjson files when importing group labels when using
    Bulk Import functionality
  - Such approach is required instead of using GraphQL
    in order to preserve epic-label association
  - Ndjson approach downloads ndjson file containing
    all source group labels and imports them

Changelog: changed

app/models/bulk_imports/export.rb

@@ -4,6 +4,10 @@ module BulkImports
   class Export < ApplicationRecord
     include Gitlab::Utils::StrongMemoize
 
+    STARTED = 0
+    FINISHED = 1
+    FAILED = -1
+
     self.table_name = 'bulk_import_exports'
 
     belongs_to :project, optional: true
@@ -18,9 +22,9 @@ module BulkImports
     validate :portable_relation?
 
     state_machine :status, initial: :started do
-      state :started, value: 0
-      state :finished, value: 1
-      state :failed, value: -1
+      state :started, value: STARTED
+      state :finished, value: FINISHED
+      state :failed, value: FAILED
 
       event :start do
         transition any => :started

app/models/bulk_imports/export_status.rb

+# frozen_string_literal: true
+
+module BulkImports
+  class ExportStatus
+    include Gitlab::Utils::StrongMemoize
+
+    def initialize(pipeline_tracker, relation)
+      @pipeline_tracker = pipeline_tracker
+      @relation = relation
+      @entity = @pipeline_tracker.entity
+      @configuration = @entity.bulk_import.configuration
+      @client = Clients::Http.new(uri: @configuration.url, token: @configuration.access_token)
+    end
+
+    def started?
+      export_status['status'] == Export::STARTED
+    end
+
+    def failed?
+      export_status['status'] == Export::FAILED
+    end
+
+    def error
+      export_status['error']
+    end
+
+    private
+
+    attr_reader :client, :entity, :relation
+
+    def export_status
+      strong_memoize(:export_status) do
+        fetch_export_status.find { |item| item['relation'] == relation }
+      end
+    rescue StandardError => e
+      { 'status' => Export::FAILED, 'error' => e.message }
+    end
+
+    def fetch_export_status
+      client.get(status_endpoint).parsed_response
+    end
+
+    def status_endpoint
+      "/groups/#{entity.encoded_source_full_path}/export_relations/status"
+    end
+  end
+end

app/models/bulk_imports/file_transfer/base_config.rb

@@ -13,6 +13,14 @@ module BulkImports
         attributes_finder.find_root(portable_class_sym)
       end
 
+      def top_relation_tree(relation)
+        portable_relations_tree[relation.to_s]
+      end
+
+      def relation_excluded_keys(relation)
+        attributes_finder.find_excluded_keys(relation)
+      end
+
       def export_path
         strong_memoize(:export_path) do
           relative_path = File.join(base_export_path, SecureRandom.hex)
@@ -47,6 +55,10 @@ module BulkImports
         @portable_class_sym ||= portable_class.to_s.demodulize.underscore.to_sym
       end
 
+      def portable_relations_tree
+        @portable_relations_tree ||= attributes_finder.find_relations_tree(portable_class_sym).deep_stringify_keys
+      end
+
       def import_export_yaml
         raise NotImplementedError
       end

app/services/bulk_imports/file_download_service.rb

@@ -3,7 +3,7 @@
 module BulkImports
   class FileDownloadService
     FILE_SIZE_LIMIT = 5.gigabytes
-    ALLOWED_CONTENT_TYPES = ['application/octet-stream'].freeze
+    ALLOWED_CONTENT_TYPES = %w(application/gzip application/octet-stream).freeze
 
     ServiceError = Class.new(StandardError)
 

app/workers/bulk_imports/pipeline_worker.rb

@@ -4,6 +4,8 @@ module BulkImports
   class PipelineWorker # rubocop:disable Scalability/IdempotentWorker
     include ApplicationWorker
 
+    NDJSON_PIPELINE_PERFORM_DELAY = 1.minute
+
     feature_category :importers
     tags :exclude_from_kubernetes
 
@@ -40,6 +42,15 @@ module BulkImports
     private
 
     def run(pipeline_tracker)
+      if ndjson_pipeline?(pipeline_tracker)
+        status = ExportStatus.new(pipeline_tracker, pipeline_tracker.pipeline_class::RELATION)
+
+        raise(Pipeline::ExpiredError, 'Pipeline timeout') if job_timeout?(pipeline_tracker)
+        raise(Pipeline::FailedError, status.error) if status.failed?
+
+        return reenqueue(pipeline_tracker) if status.started?
+      end
+
       pipeline_tracker.update!(status_event: 'start', jid: jid)
 
       context = ::BulkImports::Pipeline::Context.new(pipeline_tracker)
@@ -48,7 +59,7 @@ module BulkImports
 
       pipeline_tracker.finish!
     rescue StandardError => e
-      pipeline_tracker.fail_op!
+      pipeline_tracker.update!(status_event: 'fail_op', jid: jid)
 
       logger.error(
         worker: self.class.name,
@@ -67,5 +78,17 @@ module BulkImports
     def logger
       @logger ||= Gitlab::Import::Logger.build
     end
+
+    def ndjson_pipeline?(pipeline_tracker)
+      pipeline_tracker.pipeline_class.ndjson_pipeline?
+    end
+
+    def job_timeout?(pipeline_tracker)
+      (Time.zone.now - pipeline_tracker.entity.created_at) > Pipeline::NDJSON_EXPORT_TIMEOUT
+    end
+
+    def reenqueue(pipeline_tracker)
+      self.class.perform_in(NDJSON_PIPELINE_PERFORM_DELAY, pipeline_tracker.id, pipeline_tracker.stage, pipeline_tracker.entity.id)
+    end
   end
 end

lib/bulk_imports/common/extractors/ndjson_extractor.rb

+# frozen_string_literal: true
+
+module BulkImports
+  module Common
+    module Extractors
+      class NdjsonExtractor
+        include Gitlab::ImportExport::CommandLineUtil
+        include Gitlab::Utils::StrongMemoize
+
+        EXPORT_DOWNLOAD_URL_PATH = "/%{resource}/%{full_path}/export_relations/download?relation=%{relation}"
+
+        def initialize(relation:)
+          @relation = relation
+          @tmp_dir = Dir.mktmpdir
+        end
+
+        def extract(context)
+          download_service(tmp_dir, context).execute
+          decompression_service(tmp_dir).execute
+          relations = ndjson_reader(tmp_dir).consume_relation('', relation)
+
+          BulkImports::Pipeline::ExtractedData.new(data: relations)
+        end
+
+        def remove_tmp_dir
+          FileUtils.remove_entry(tmp_dir)
+        end
+
+        private
+
+        attr_reader :relation, :tmp_dir
+
+        def filename
+          @filename ||= "#{relation}.ndjson.gz"
+        end
+
+        def download_service(tmp_dir, context)
+          @download_service ||= BulkImports::FileDownloadService.new(
+            configuration: context.configuration,
+            relative_url: relative_resource_url(context),
+            dir: tmp_dir,
+            filename: filename
+          )
+        end
+
+        def decompression_service(tmp_dir)
+          @decompression_service ||= BulkImports::FileDecompressionService.new(
+            dir: tmp_dir,
+            filename: filename
+          )
+        end
+
+        def ndjson_reader(tmp_dir)
+          @ndjson_reader ||= Gitlab::ImportExport::JSON::NdjsonReader.new(tmp_dir)
+        end
+
+        def relative_resource_url(context)
+          strong_memoize(:relative_resource_url) do
+            resource = context.portable.class.name.downcase.pluralize
+            encoded_full_path = context.entity.encoded_source_full_path
+
+            EXPORT_DOWNLOAD_URL_PATH % { resource: resource, full_path: encoded_full_path, relation: relation }
+          end
+        end
+      end
+    end
+  end
+end

lib/bulk_imports/groups/graphql/get_labels_query.rb

-# frozen_string_literal: true
-
-module BulkImports
-  module Groups
-    module Graphql
-      module GetLabelsQuery
-        extend self
-
-        def to_s
-          <<-'GRAPHQL'
-          query ($full_path: ID!, $cursor: String, $per_page: Int) {
-            group(fullPath: $full_path) {
-              labels(first: $per_page, after: $cursor, onlyGroupLabels: true) {
-                page_info: pageInfo {
-                  next_page: endCursor
-                  has_next_page: hasNextPage
-                }
-                nodes {
-                  title
-                  description
-                  color
-                  created_at: createdAt
-                  updated_at: updatedAt
-                }
-              }
-            }
-          }
-          GRAPHQL
-        end
-
-        def variables(context)
-          {
-            full_path: context.entity.source_full_path,
-            cursor: context.tracker.next_page,
-            per_page: ::BulkImports::Tracker::DEFAULT_PAGE_SIZE
-          }
-        end
-
-        def base_path
-          %w[data group labels]
-        end
-
-        def data_path
-          base_path << 'nodes'
-        end
-
-        def page_info_path
-          base_path << 'page_info'
-        end
-      end
-    end
-  end
-end

lib/bulk_imports/groups/pipelines/entity_finisher.rb

@@ -4,6 +4,10 @@ module BulkImports
   module Groups
     module Pipelines
       class EntityFinisher
+        def self.ndjson_pipeline?
+          false
+        end
+
         def initialize(context)
           @context = context
         end

lib/bulk_imports/groups/pipelines/labels_pipeline.rb

@@ -4,15 +4,35 @@ module BulkImports
   module Groups
     module Pipelines
       class LabelsPipeline
-        include Pipeline
+        include NdjsonPipeline
 
-        extractor BulkImports::Common::Extractors::GraphqlExtractor,
-          query: BulkImports::Groups::Graphql::GetLabelsQuery
+        RELATION = 'labels'
 
-        transformer Common::Transformers::ProhibitedAttributesTransformer
+        extractor ::BulkImports::Common::Extractors::NdjsonExtractor, relation: RELATION
 
-        def load(context, data)
-          Labels::CreateService.new(data).execute(group: context.group)
+        def transform(context, data)
+          relation_hash = data.first
+          relation_index = data.last
+          relation_definition = import_export_config.top_relation_tree(RELATION)
+
+          deep_transform_relation!(relation_hash, RELATION, relation_definition) do |key, hash|
+            Gitlab::ImportExport::Group::RelationFactory.create(
+              relation_index: relation_index,
+              relation_sym: key.to_sym,
+              relation_hash: hash,
+              importable: context.portable,
+              members_mapper: nil,
+              object_builder: object_builder,
+              user: context.current_user,
+              excluded_keys: import_export_config.relation_excluded_keys(key)
+            )
+          end
+        end
+
+        def load(_, label)
+          return unless label
+
+          label.save! unless label.persisted?
         end
       end
     end

lib/bulk_imports/ndjson_pipeline.rb

+# frozen_string_literal: true
+
+module BulkImports
+  module NdjsonPipeline
+    extend ActiveSupport::Concern
+
+    include Pipeline
+
+    included do
+      ndjson_pipeline!
+
+      def deep_transform_relation!(relation_hash, relation_key, relation_definition, &block)
+        relation_key = relation_key_override(relation_key)
+
+        relation_definition.each do |sub_relation_key, sub_relation_definition|
+          sub_relation = relation_hash[sub_relation_key]
+
+          next unless sub_relation
+
+          current_item =
+            if sub_relation.is_a?(Array)
+              sub_relation
+                .map { |entry| deep_transform_relation!(entry, sub_relation_key, sub_relation_definition, &block) }
+                .tap { |entry| entry.compact! }
+                .presence
+            else
+              deep_transform_relation!(sub_relation, sub_relation_key, sub_relation_definition, &block)
+            end
+
+          if current_item
+            relation_hash[sub_relation_key] = current_item
+          else
+            relation_hash.delete(sub_relation_key)
+          end
+        end
+
+        yield(relation_key, relation_hash)
+      end
+
+      def after_run(_)
+        extractor.remove_tmp_dir if extractor.respond_to?(:remove_tmp_dir)
+      end
+
+      def relation_class(relation_key)
+        relation_key.to_s.classify.constantize
+      rescue NameError
+        relation_key.to_s.constantize
+      end
+
+      def relation_key_override(relation_key)
+        relation_key_overrides[relation_key.to_sym]&.to_s || relation_key
+      end
+
+      def relation_key_overrides
+        "Gitlab::ImportExport::#{portable.class}::RelationFactory::OVERRIDES".constantize
+      end
+
+      def object_builder
+        "Gitlab::ImportExport::#{portable.class}::ObjectBuilder".constantize
+      end
+    end
+  end
+end

lib/bulk_imports/pipeline.rb

@@ -8,8 +8,11 @@ module BulkImports
     include Runner
 
     NotAllowedError = Class.new(StandardError)
+    ExpiredError = Class.new(StandardError)
+    FailedError = Class.new(StandardError)
 
     CACHE_KEY_EXPIRATION = 2.hours
+    NDJSON_EXPORT_TIMEOUT = 30.minutes
 
     def initialize(context)
       @context = context
@@ -19,6 +22,14 @@ module BulkImports
       @tracker ||= context.tracker
     end
 
+    def portable
+      @portable ||= context.portable
+    end
+
+    def import_export_config
+      @import_export_config ||= context.import_export_config
+    end
+
     included do
       private
 
@@ -111,7 +122,7 @@ module BulkImports
         options = class_config[:options]
 
         if options
-          class_config[:klass].new(class_config[:options])
+          class_config[:klass].new(**class_config[:options])
         else
           class_config[:klass].new
         end
@@ -155,6 +166,14 @@ module BulkImports
         class_attributes[:abort_on_failure]
       end
 
+      def ndjson_pipeline!
+        class_attributes[:ndjson_pipeline] = true
+      end
+
+      def ndjson_pipeline?
+        class_attributes[:ndjson_pipeline]
+      end
+
       private
 
       def add_attribute(sym, klass, options)

lib/bulk_imports/pipeline/context.rb

@@ -16,6 +16,14 @@ module BulkImports
         @entity ||= tracker.entity
       end
 
+      def portable
+        @portable ||= entity.group || entity.project
+      end
+
+      def import_export_config
+        @import_export_config ||= ::BulkImports::FileTransfer.config_for(portable)
+      end
+
       def group
         @group ||= entity.group
       end

lib/bulk_imports/pipeline/extracted_data.rb

@@ -6,7 +6,7 @@ module BulkImports
       attr_reader :data
 
       def initialize(data: nil, page_info: {})
-        @data = Array.wrap(data)
+        @data = data.is_a?(Enumerator) ? data : Array.wrap(data)
         @page_info = page_info
       end
 

spec/lib/bulk_imports/common/extractors/ndjson_extractor_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe BulkImports::Common::Extractors::NdjsonExtractor do
+  let_it_be(:tmpdir) { Dir.mktmpdir }
+  let_it_be(:filepath) { 'spec/fixtures/bulk_imports/labels.ndjson.gz' }
+  let_it_be(:import) { create(:bulk_import) }
+  let_it_be(:config) { create(:bulk_import_configuration, bulk_import: import) }
+  let_it_be(:entity) { create(:bulk_import_entity, bulk_import: import) }
+  let_it_be(:tracker) { create(:bulk_import_tracker, entity: entity) }
+  let_it_be(:context) { BulkImports::Pipeline::Context.new(tracker) }
+
+  subject { described_class.new(relation: 'labels') }
+
+  before do
+    allow(FileUtils).to receive(:remove_entry).with(any_args).and_call_original
+
+    subject.instance_variable_set(:@tmp_dir, tmpdir)
+  end
+
+  after(:all) do
+    FileUtils.remove_entry(tmpdir) if File.directory?(tmpdir)
+  end
+
+  describe '#extract' do
+    before do
+      FileUtils.copy_file(filepath, File.join(tmpdir, 'labels.ndjson.gz'))
+
+      allow_next_instance_of(BulkImports::FileDownloadService) do |service|
+        allow(service).to receive(:execute)
+      end
+    end
+
+    it 'returns ExtractedData' do
+      extracted_data = subject.extract(context)
+      label = extracted_data.data.first.first
+
+      expect(extracted_data).to be_instance_of(BulkImports::Pipeline::ExtractedData)
+      expect(label['title']).to include('Label')
+      expect(label['description']).to include('Label')
+      expect(label['type']).to eq('GroupLabel')
+    end
+  end
+
+  describe '#remove_tmp_dir' do
+    it 'removes tmp dir' do
+      expect(FileUtils).to receive(:remove_entry).with(tmpdir).once
+
+      subject.remove_tmp_dir
+    end
+  end
+end

spec/lib/bulk_imports/groups/graphql/get_labels_query_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-RSpec.describe BulkImports::Groups::Graphql::GetLabelsQuery do
-  it 'has a valid query' do
-    tracker = create(:bulk_import_tracker)
-    context = BulkImports::Pipeline::Context.new(tracker)
-
-    query = GraphQL::Query.new(
-      GitlabSchema,
-      described_class.to_s,
-      variables: described_class.variables(context)
-    )
-    result = GitlabSchema.static_validator.validate(query)
-
-    expect(result[:errors]).to be_empty
-  end
-
-  describe '#data_path' do
-    it 'returns data path' do
-      expected = %w[data group labels nodes]
-
-      expect(described_class.data_path).to eq(expected)
-    end
-  end
-
-  describe '#page_info_path' do
-    it 'returns pagination information path' do
-      expected = %w[data group labels page_info]
-
-      expect(described_class.page_info_path).to eq(expected)
-    end
-  end
-end

spec/lib/bulk_imports/groups/pipelines/labels_pipeline_spec.rb

@@ -5,98 +5,87 @@ require 'spec_helper'
 RSpec.describe BulkImports::Groups::Pipelines::LabelsPipeline do
   let_it_be(:user) { create(:user) }
   let_it_be(:group) { create(:group) }
-  let_it_be(:timestamp) { Time.new(2020, 01, 01).utc }
-
+  let_it_be(:bulk_import) { create(:bulk_import, user: user) }
+  let_it_be(:filepath) { 'spec/fixtures/bulk_imports/labels.ndjson.gz' }
   let_it_be(:entity) do
     create(
       :bulk_import_entity,
+      group: group,
+      bulk_import: bulk_import,
       source_full_path: 'source/full/path',
       destination_name: 'My Destination Group',
-      destination_namespace: group.full_path,
-      group: group
+      destination_namespace: group.full_path
     )
   end
 
   let_it_be(:tracker) { create(:bulk_import_tracker, entity: entity) }
   let_it_be(:context) { BulkImports::Pipeline::Context.new(tracker) }
 
+  let(:tmpdir) { Dir.mktmpdir }
+
+  before do
+    FileUtils.copy_file(filepath, File.join(tmpdir, 'labels.ndjson.gz'))
+    group.add_owner(user)
+  end
+
   subject { described_class.new(context) }
 
   describe '#run' do
-    it 'imports a group labels' do
-      first_page = extracted_data(title: 'label1', has_next_page: true)
-      last_page = extracted_data(title: 'label2')
-
-      allow_next_instance_of(BulkImports::Common::Extractors::GraphqlExtractor) do |extractor|
-        allow(extractor)
-          .to receive(:extract)
-          .and_return(first_page, last_page)
+    it 'imports group labels into destination group and removes tmpdir' do
+      allow(Dir).to receive(:mktmpdir).and_return(tmpdir)
+      allow_next_instance_of(BulkImports::FileDownloadService) do |service|
+        allow(service).to receive(:execute)
       end
 
-      expect { subject.run }.to change(Label, :count).by(2)
+      expect { subject.run }.to change(::GroupLabel, :count).by(1)
 
-      label = group.labels.order(:created_at).last
+      label = group.labels.first
 
-      expect(label.title).to eq('label2')
-      expect(label.description).to eq('desc')
-      expect(label.color).to eq('#428BCA')
-      expect(label.created_at).to eq(timestamp)
-      expect(label.updated_at).to eq(timestamp)
+      expect(label.title).to eq('Label 1')
+      expect(label.description).to eq('Label 1')
+      expect(label.color).to eq('#6699cc')
+      expect(File.directory?(tmpdir)).to eq(false)
     end
   end
 
   describe '#load' do
-    it 'creates the label' do
-      data = label_data('label')
+    context 'when label is not persisted' do
+      it 'saves the label' do
+        label = build(:group_label, group: group)
 
-      expect { subject.load(context, data) }.to change(Label, :count).by(1)
+        expect(label).to receive(:save!)
 
-      label = group.labels.first
+        subject.load(context, label)
+      end
+    end
+
+    context 'when label is persisted' do
+      it 'does not save label' do
+        label = create(:group_label, group: group)
 
-      data.each do |key, value|
-        expect(label[key]).to eq(value)
+        expect(label).not_to receive(:save!)
+
+        subject.load(context, label)
+      end
+    end
+
+    context 'when label is missing' do
+      it 'returns' do
+        expect(subject.load(context, nil)).to be_nil
       end
     end
   end
 
   describe 'pipeline parts' do
-    it { expect(described_class).to include_module(BulkImports::Pipeline) }
+    it { expect(described_class).to include_module(BulkImports::NdjsonPipeline) }
     it { expect(described_class).to include_module(BulkImports::Pipeline::Runner) }
 
-    it 'has extractors' do
+    it 'has extractor' do
       expect(described_class.get_extractor)
         .to eq(
-          klass: BulkImports::Common::Extractors::GraphqlExtractor,
-          options: {
-            query: BulkImports::Groups::Graphql::GetLabelsQuery
-          }
-        )
-    end
-
-    it 'has transformers' do
-      expect(described_class.transformers)
-        .to contain_exactly(
-          { klass: BulkImports::Common::Transformers::ProhibitedAttributesTransformer, options: nil }
+          klass: BulkImports::Common::Extractors::NdjsonExtractor,
+          options: { relation: described_class::RELATION }
         )
     end
   end
-
-  def label_data(title)
-    {
-      'title' => title,
-      'description' => 'desc',
-      'color' => '#428BCA',
-      'created_at' => timestamp.to_s,
-      'updated_at' => timestamp.to_s
-    }
-  end
-
-  def extracted_data(title:, has_next_page: false)
-    page_info = {
-      'has_next_page' => has_next_page,
-      'next_page' => has_next_page ? 'cursor' : nil
-    }
-
-    BulkImports::Pipeline::ExtractedData.new(data: [label_data(title)], page_info: page_info)
-  end
 end

spec/lib/bulk_imports/ndjson_pipeline_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe BulkImports::NdjsonPipeline do
+  let_it_be(:group) { create(:group) }
+  let_it_be(:project) { create(:project) }
+  let_it_be(:klass) do
+    Class.new do
+      include BulkImports::NdjsonPipeline
+
+      attr_reader :portable
+
+      def initialize(portable)
+        @portable = portable
+      end
+    end
+  end
+
+  subject { klass.new(group) }
+
+  it 'marks pipeline as ndjson' do
+    expect(klass.ndjson_pipeline?).to eq(true)
+  end
+
+  describe '#deep_transform_relation!' do
+    it 'transforms relation hash' do
+      transformed = subject.deep_transform_relation!({}, 'test', {}) do |key, hash|
+        hash.merge(relation_key: key)
+      end
+
+      expect(transformed[:relation_key]).to eq('test')
+    end
+
+    context 'when subrelations is an array' do
+      it 'transforms each element of the array' do
+        relation_hash = {
+          'key' => 'value',
+          'labels' => [
+            { 'title' => 'label 1' },
+            { 'title' => 'label 2' },
+            { 'title' => 'label 3' }
+          ]
+        }
+        relation_definition = { 'labels' => {} }
+
+        transformed = subject.deep_transform_relation!(relation_hash, 'test', relation_definition) do |key, hash|
+          hash.merge(relation_key: key)
+        end
+
+        transformed['labels'].each do |label|
+          expect(label[:relation_key]).to eq('group_labels')
+        end
+      end
+    end
+
+    context 'when subrelation is a hash' do
+      it 'transforms subrelation hash' do
+        relation_hash = {
+          'key' => 'value',
+          'label' => { 'title' => 'label' }
+        }
+        relation_definition = { 'label' => {} }
+
+        transformed = subject.deep_transform_relation!(relation_hash, 'test', relation_definition) do |key, hash|
+          hash.merge(relation_key: key)
+        end
+
+        expect(transformed['label'][:relation_key]).to eq('group_label')
+      end
+    end
+
+    context 'when subrelation is nil' do
+      it 'removes subrelation' do
+        relation_hash = {
+          'key' => 'value',
+          'label' => { 'title' => 'label' }
+        }
+        relation_definition = { 'label' => {} }
+
+        transformed = subject.deep_transform_relation!(relation_hash, 'test', relation_definition) do |key, hash|
+          if key == 'group_label'
+            nil
+          else
+            hash
+          end
+        end
+
+        expect(transformed['label']).to be_nil
+      end
+    end
+  end
+
+  describe '#relation_class' do
+    context 'when relation name is pluralized' do
+      it 'returns constantized class' do
+        expect(subject.relation_class('MergeRequest::Metrics')).to eq(MergeRequest::Metrics)
+      end
+    end
+
+    context 'when relation name is singularized' do
+      it 'returns constantized class' do
+        expect(subject.relation_class('Badge')).to eq(Badge)
+      end
+    end
+  end
+
+  describe '#relation_key_override' do
+    context 'when portable is group' do
+      it 'returns group relation name override' do
+        expect(subject.relation_key_override('labels')).to eq('group_labels')
+      end
+    end
+
+    context 'when portable is project' do
+      subject { klass.new(project) }
+
+      it 'returns group relation name override' do
+        expect(subject.relation_key_override('labels')).to eq('project_labels')
+      end
+    end
+  end
+end

spec/lib/bulk_imports/pipeline/context_spec.rb

@@ -6,6 +6,9 @@ RSpec.describe BulkImports::Pipeline::Context do
   let_it_be(:user) { create(:user) }
   let_it_be(:group) { create(:group) }
   let_it_be(:bulk_import) { create(:bulk_import, user: user) }
+  let_it_be(:project) { create(:project) }
+  let_it_be(:project_entity) { create(:bulk_import_entity, :project_entity, project: project) }
+  let_it_be(:project_tracker) { create(:bulk_import_tracker, entity: project_entity) }
 
   let_it_be(:entity) do
     create(
@@ -51,4 +54,24 @@ RSpec.describe BulkImports::Pipeline::Context do
   describe '#extra' do
     it { expect(subject.extra).to eq(extra: :data) }
   end
+
+  describe '#portable' do
+    it { expect(subject.portable).to eq(group) }
+
+    context 'when portable is project' do
+      subject { described_class.new(project_tracker) }
+
+      it { expect(subject.portable).to eq(project) }
+    end
+  end
+
+  describe '#import_export_config' do
+    it { expect(subject.import_export_config).to be_instance_of(BulkImports::FileTransfer::GroupConfig) }
+
+    context 'when portable is project' do
+      subject { described_class.new(project_tracker) }
+
+      it { expect(subject.import_export_config).to be_instance_of(BulkImports::FileTransfer::ProjectConfig) }
+    end
+  end
 end

spec/lib/bulk_imports/pipeline_spec.rb

@@ -63,6 +63,7 @@ RSpec.describe BulkImports::Pipeline do
         BulkImports::MyPipeline.transformer(klass, options)
         BulkImports::MyPipeline.loader(klass, options)
         BulkImports::MyPipeline.abort_on_failure!
+        BulkImports::MyPipeline.ndjson_pipeline!
 
         expect(BulkImports::MyPipeline.get_extractor).to eq({ klass: klass, options: options })
 
@@ -74,6 +75,7 @@ RSpec.describe BulkImports::Pipeline do
         expect(BulkImports::MyPipeline.get_loader).to eq({ klass: klass, options: options })
 
         expect(BulkImports::MyPipeline.abort_on_failure?).to eq(true)
+        expect(BulkImports::MyPipeline.ndjson_pipeline?).to eq(true)
       end
     end
   end

spec/models/bulk_imports/export_status_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe BulkImports::ExportStatus do
+  let_it_be(:relation) { 'labels' }
+  let_it_be(:import) { create(:bulk_import) }
+  let_it_be(:config) { create(:bulk_import_configuration, bulk_import: import) }
+  let_it_be(:entity) { create(:bulk_import_entity, bulk_import: import, source_full_path: 'foo') }
+  let_it_be(:tracker) { create(:bulk_import_tracker, entity: entity) }
+
+  let(:response_double) do
+    double(parsed_response: [{ 'relation' => 'labels', 'status' => status, 'error' => 'error!' }])
+  end
+
+  subject { described_class.new(tracker, relation) }
+
+  before do
+    allow_next_instance_of(BulkImports::Clients::Http) do |client|
+      allow(client).to receive(:get).and_return(response_double)
+    end
+  end
+
+  describe '#started?' do
+    context 'when export status is started' do
+      let(:status) { BulkImports::Export::STARTED }
+
+      it 'returns true' do
+        expect(subject.started?).to eq(true)
+      end
+    end
+
+    context 'when export status is not started' do
+      let(:status) { BulkImports::Export::FAILED }
+
+      it 'returns false' do
+        expect(subject.started?).to eq(false)
+      end
+    end
+  end
+
+  describe '#failed' do
+    context 'when export status is failed' do
+      let(:status) { BulkImports::Export::FAILED }
+
+      it 'returns true' do
+        expect(subject.failed?).to eq(true)
+      end
+    end
+
+    context 'when export status is not failed' do
+      let(:status) { BulkImports::Export::STARTED }
+
+      it 'returns false' do
+        expect(subject.failed?).to eq(false)
+      end
+    end
+  end
+
+  describe '#error' do
+    let(:status) { BulkImports::Export::FAILED }
+
+    it 'returns error message' do
+      expect(subject.error).to eq('error!')
+    end
+
+    context 'when something goes wrong during export status fetch' do
+      it 'returns exception class as error' do
+        allow_next_instance_of(BulkImports::Clients::Http) do |client|
+          allow(client).to receive(:get).and_raise(StandardError, 'Error!')
+        end
+
+        expect(subject.error).to eq('Error!')
+      end
+    end
+  end
+end

spec/models/bulk_imports/file_transfer/group_config_spec.rb

@@ -12,8 +12,8 @@ RSpec.describe BulkImports::FileTransfer::GroupConfig do
 
   subject { described_class.new(exportable) }
 
-  describe '#exportable_tree' do
-    it 'returns exportable tree' do
+  describe '#portable_tree' do
+    it 'returns portable tree' do
       expect_next_instance_of(::Gitlab::ImportExport::AttributesFinder) do |finder|
         expect(finder).to receive(:find_root).with(:group).and_call_original
       end
@@ -30,9 +30,21 @@ RSpec.describe BulkImports::FileTransfer::GroupConfig do
     end
   end
 
-  describe '#exportable_relations' do
+  describe '#portable_relations' do
     it 'returns a list of top level exportable relations' do
       expect(subject.portable_relations).to include('milestones', 'badges', 'boards', 'labels')
     end
   end
+
+  describe '#top_relation_tree' do
+    it 'returns relation tree of a top level relation' do
+      expect(subject.top_relation_tree('labels')).to eq('priorities' => {})
+    end
+  end
+
+  describe '#relation_excluded_keys' do
+    it 'returns excluded keys for relation' do
+      expect(subject.relation_excluded_keys('group')).to include('owner_id')
+    end
+  end
 end

spec/models/bulk_imports/file_transfer/project_config_spec.rb

@@ -12,8 +12,8 @@ RSpec.describe BulkImports::FileTransfer::ProjectConfig do
 
   subject { described_class.new(exportable) }
 
-  describe '#exportable_tree' do
-    it 'returns exportable tree' do
+  describe 'portable_tree' do
+    it 'returns portable tree' do
       expect_next_instance_of(::Gitlab::ImportExport::AttributesFinder) do |finder|
         expect(finder).to receive(:find_root).with(:project).and_call_original
       end
@@ -30,9 +30,21 @@ RSpec.describe BulkImports::FileTransfer::ProjectConfig do
     end
   end
 
-  describe '#exportable_relations' do
+  describe '#portable_relations' do
     it 'returns a list of top level exportable relations' do
       expect(subject.portable_relations).to include('issues', 'labels', 'milestones', 'merge_requests')
     end
   end
+
+  describe '#top_relation_tree' do
+    it 'returns relation tree of a top level relation' do
+      expect(subject.top_relation_tree('labels')).to eq('priorities' => {})
+    end
+  end
+
+  describe '#relation_excluded_keys' do
+    it 'returns excluded keys for relation' do
+      expect(subject.relation_excluded_keys('project')).to include('creator_id')
+    end
+  end
 end

spec/services/bulk_imports/file_download_service_spec.rb

@@ -32,11 +32,21 @@ RSpec.describe BulkImports::FileDownloadService do
       end
     end
 
-    it 'downloads file' do
-      subject.execute
+    shared_examples 'downloads file' do
+      it 'downloads file' do
+        subject.execute
 
-      expect(File.exist?(filepath)).to eq(true)
-      expect(File.read(filepath)).to include('chunk')
+        expect(File.exist?(filepath)).to eq(true)
+        expect(File.read(filepath)).to include('chunk')
+      end
+    end
+
+    include_examples 'downloads file'
+
+    context 'when content-type is application/gzip' do
+      let_it_be(:content_type) { 'application/gzip' }
+
+      include_examples 'downloads file'
     end
 
     context 'when url is not valid' do

spec/workers/bulk_imports/pipeline_worker_spec.rb

@@ -8,10 +8,16 @@ RSpec.describe BulkImports::PipelineWorker do
       def initialize(_); end
 
       def run; end
+
+      def self.ndjson_pipeline?
+        false
+      end
     end
   end
 
-  let_it_be(:entity) { create(:bulk_import_entity) }
+  let_it_be(:bulk_import) { create(:bulk_import) }
+  let_it_be(:config) { create(:bulk_import_configuration, bulk_import: bulk_import) }
+  let_it_be(:entity) { create(:bulk_import_entity, bulk_import: bulk_import) }
 
   before do
     stub_const('FakePipeline', pipeline_class)
@@ -27,6 +33,7 @@ RSpec.describe BulkImports::PipelineWorker do
     expect(BulkImports::Stage)
       .to receive(:pipeline_exists?)
       .with('FakePipeline')
+      .twice
       .and_return(true)
 
     expect_next_instance_of(Gitlab::Import::Logger) do |logger|
@@ -122,4 +129,114 @@ RSpec.describe BulkImports::PipelineWorker do
       expect(pipeline_tracker.jid).to eq('jid')
     end
   end
+
+  context 'when ndjson pipeline' do
+    let(:ndjson_pipeline) do
+      Class.new do
+        def initialize(_); end
+
+        def run; end
+
+        def self.ndjson_pipeline?
+          true
+        end
+      end
+    end
+
+    let(:pipeline_tracker) do
+      create(
+        :bulk_import_tracker,
+        entity: entity,
+        pipeline_name: 'NdjsonPipeline'
+      )
+    end
+
+    before do
+      stub_const('NdjsonPipeline', ndjson_pipeline)
+      stub_const('NdjsonPipeline::RELATION', 'test')
+      allow(BulkImports::Stage)
+        .to receive(:pipeline_exists?)
+        .with('NdjsonPipeline')
+        .and_return(true)
+    end
+
+    it 'runs the pipeline successfully' do
+      allow_next_instance_of(BulkImports::ExportStatus) do |status|
+        allow(status).to receive(:started?).and_return(false)
+        allow(status).to receive(:failed?).and_return(false)
+      end
+
+      subject.perform(pipeline_tracker.id, pipeline_tracker.stage, entity.id)
+
+      expect(pipeline_tracker.reload.status_name).to eq(:finished)
+    end
+
+    context 'when export status is started' do
+      it 'reenqueues pipeline worker' do
+        allow_next_instance_of(BulkImports::ExportStatus) do |status|
+          allow(status).to receive(:started?).and_return(true)
+          allow(status).to receive(:failed?).and_return(false)
+        end
+
+        expect(described_class)
+          .to receive(:perform_in)
+          .with(
+            described_class::NDJSON_PIPELINE_PERFORM_DELAY,
+            pipeline_tracker.id,
+            pipeline_tracker.stage,
+            entity.id
+          )
+
+        subject.perform(pipeline_tracker.id, pipeline_tracker.stage, entity.id)
+      end
+    end
+
+    context 'when job reaches timeout' do
+      it 'marks as failed and logs the error' do
+        old_created_at = entity.created_at
+        entity.update!(created_at: (BulkImports::Pipeline::NDJSON_EXPORT_TIMEOUT + 1.hour).ago)
+
+        expect_next_instance_of(Gitlab::Import::Logger) do |logger|
+          expect(logger)
+            .to receive(:error)
+            .with(
+              worker: described_class.name,
+              pipeline_name: 'NdjsonPipeline',
+              entity_id: entity.id,
+              message: 'Pipeline timeout'
+            )
+        end
+
+        subject.perform(pipeline_tracker.id, pipeline_tracker.stage, entity.id)
+
+        expect(pipeline_tracker.reload.status_name).to eq(:failed)
+
+        entity.update!(created_at: old_created_at)
+      end
+    end
+
+    context 'when export status is failed' do
+      it 'marks as failed and logs the error' do
+        allow_next_instance_of(BulkImports::ExportStatus) do |status|
+          allow(status).to receive(:failed?).and_return(true)
+          allow(status).to receive(:error).and_return('Error!')
+        end
+
+        expect_next_instance_of(Gitlab::Import::Logger) do |logger|
+          expect(logger)
+            .to receive(:error)
+            .with(
+              worker: described_class.name,
+              pipeline_name: 'NdjsonPipeline',
+              entity_id: entity.id,
+              message: 'Error!'
+            )
+        end
+
+        subject.perform(pipeline_tracker.id, pipeline_tracker.stage, entity.id)
+
+        expect(pipeline_tracker.reload.status_name).to eq(:failed)
+      end
+    end
+  end
 end