1 files changed, 52 insertions, 0 deletions
diff --git a/lib/bulk_imports/common/extractors/json_extractor.rb b/lib/bulk_imports/common/extractors/json_extractor.rb
new file mode 100644
index 00000000000..45a48cedce8
--- /dev/null
+++ b/lib/bulk_imports/common/extractors/json_extractor.rb
@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+module BulkImports
+  module Common
+    module Extractors
+      class JsonExtractor
+        def initialize(relation:)
+          @relation = relation
+          @tmpdir = Dir.mktmpdir
+        end
+
+        def extract(context)
+          download_service(context).execute
+          decompression_service.execute
+
+          attributes = ndjson_reader.consume_attributes(relation)
+
+          BulkImports::Pipeline::ExtractedData.new(data: attributes)
+        end
+
+        def remove_tmpdir
+          FileUtils.remove_entry(tmpdir) if Dir.exist?(tmpdir)
+        end
+
+        private
+
+        attr_reader :relation, :tmpdir
+
+        def filename
+          "#{relation}.json.gz"
+        end
+
+        def download_service(context)
+          @download_service ||= BulkImports::FileDownloadService.new(
+            configuration: context.configuration,
+            relative_url: context.entity.relation_download_url_path(relation),
+            tmpdir: tmpdir,
+            filename: filename
+          )
+        end
+
+        def decompression_service
+          @decompression_service ||= BulkImports::FileDecompressionService.new(tmpdir: tmpdir, filename: filename)
+        end
+
+        def ndjson_reader
+          @ndjson_reader ||= Gitlab::ImportExport::Json::NdjsonReader.new(tmpdir)
+        end
+      end
+    end
+  end
+end