REST API: Site endpoint: Return last import engine used in options ar…

…ray (#13753)

* REST API: Site endpoint: Return last import engine used in options array

Summary: This Diff adds `import_engine` to the response of the site endpoint. It returns the engine that was last used on the blog from the last `import_done` action.

Test Plan:
* Apply Diff and sandbox `public-api`
* Verify that after successfully completing an import ([which involves running async jobs when the api is sandboxed](https://fieldguide.automattic.com/imports-and-exports/running-imports-on-a-wpcom-sandbox/)) that you see the `import_engine` option set appropriately. This can be tested in coordination with Automattic/wp-calypso#36272

Reviewers: #samus_team, gn00n

Reviewed By: #samus_team, gn00n

Subscribers: gn00n, mattormeeple

Tags: #touches_jetpack_files

Differential Revision: D33115-code

This commit syncs r197917-wpcom.

* Add missing method to fix failing tests

json-endpoints/class.wpcom-json-api-get-site-endpoint.php

@@ -133,6 +133,7 @@ class WPCOM_JSON_API_GET_Site_Endpoint extends WPCOM_JSON_API_Endpoint {
 		'design_type',
 		'site_goals',
 		'site_segment',
+		'import_engine',
 	);
 
 	protected static $jetpack_response_field_additions = array(
@@ -585,6 +586,9 @@ protected function render_option_keys( &$options_response_keys ) {
 				case 'site_segment':
 					$options[ $key ] = $site->get_site_segment();
 					break;
+				case 'import_engine':
+					$options[ $key ] = $site->get_import_engine();
+					break;
 			}
 		}
 

sal/class.json-api-site-base.php

@@ -93,6 +93,8 @@ abstract public function get_ak_vp_bundle_enabled();
 
 	abstract public function get_podcasting_archive();
 
+	abstract public function get_import_engine();
+
 	abstract public function get_jetpack_seo_front_page_description();
 
 	abstract public function get_jetpack_seo_title_formats();

sal/class.json-api-site-jetpack.php

@@ -204,6 +204,15 @@ function is_fse_active() {
 		return function_exists( '\A8C\FSE\is_full_site_editing_active' ) && \A8C\FSE\is_full_site_editing_active();
 	}
 
+	/**
+	 * Return the last engine used for an import on the site.
+	 *
+	 * This option is not used in Jetpack.
+	 */
+	function get_import_engine() {
+		return null;
+	}
+
 	/**
 	 * Post functions
 	 */