1 files changed, 54 insertions, 0 deletions
diff --git a/app/services/ci/components/fetch_service.rb b/app/services/ci/components/fetch_service.rb
new file mode 100644
index 00000000000..45abb415174
--- /dev/null
+++ b/app/services/ci/components/fetch_service.rb
@@ -0,0 +1,54 @@
+# frozen_string_literal: true
+
+module Ci
+  module Components
+    class FetchService
+      include Gitlab::Utils::StrongMemoize
+
+      TEMPLATE_FILE = 'template.yml'
+
+      COMPONENT_PATHS = [
+        ::Gitlab::Ci::Components::InstancePath
+      ].freeze
+
+      def initialize(address:, current_user:)
+        @address = address
+        @current_user = current_user
+      end
+
+      def execute
+        unless component_path_class
+          return ServiceResponse.error(
+            message: "#{error_prefix} the component path is not supported",
+            reason: :unsupported_path)
+        end
+
+        component_path = component_path_class.new(address: address, content_filename: TEMPLATE_FILE)
+        content = component_path.fetch_content!(current_user: current_user)
+
+        if content.present?
+          ServiceResponse.success(payload: { content: content, path: component_path })
+        else
+          ServiceResponse.error(message: "#{error_prefix} content not found", reason: :content_not_found)
+        end
+      rescue Gitlab::Access::AccessDeniedError
+        ServiceResponse.error(
+          message: "#{error_prefix} project does not exist or you don't have sufficient permissions",
+          reason: :not_allowed)
+      end
+
+      private
+
+      attr_reader :current_user, :address
+
+      def component_path_class
+        COMPONENT_PATHS.find { |klass| klass.match?(address) }
+      end
+      strong_memoize_attr :component_path_class
+
+      def error_prefix
+        "component '#{address}' -"
+      end
+    end
+  end
+end