Deprecate API v2 (#7761)

* deprecate api-v2

* remove v2 test helpers

* remove unused string

website/server/middlewares/maintenanceMode.js

@@ -0,0 +1,31 @@
+import { getUserLanguage } from './language';
+import nconf from 'nconf';
+
+const MAINTENANCE_MODE = nconf.get('MAINTENANCE_MODE');
+
+module.exports = function maintenanceMode (req, res, next) {
+  if (MAINTENANCE_MODE !== 'true') return next();
+
+  getUserLanguage(req, res, (err) => {
+    if (err) return next(err);
+
+    let pageVariables = {
+      maintenanceStart: nconf.get('MAINTENANCE_START'),
+      maintenanceEnd: nconf.get('MAINTENANCE_END'),
+      translation: res.t,
+    };
+
+    if (req.headers && req.headers.accept && req.headers.accept.indexOf('text/html') !== -1) {
+      if (req.path === '/views/static/maintenance-info') {
+        return res.status(503).render('../../views/static/maintenance-info', pageVariables);
+      } else {
+        return res.status(503).render('../../views/static/maintenance', pageVariables);
+      }
+    } else {
+      return res.status(503).send({
+        error: 'Maintenance',
+        message: 'Server offline for maintenance.',
+      });
+    }
+  });
+};