Implement session caching.

lib/session.js

@@ -1,6 +1,6 @@
 import { getWebsiteByUuid, getSessionByUuid, createSession } from 'lib/queries';
 import { getClientInfo } from 'lib/request';
-import { uuid, isValidUuid } from 'lib/crypto';
+import { uuid, isValidUuid, parseToken } from 'lib/crypto';
 
 export async function getSession(req) {
   const { payload } = req.body;
@@ -9,7 +9,15 @@ export async function getSession(req) {
     throw new Error('Invalid request');
   }
 
-  const { website: website_uuid, hostname, screen, language } = payload;
+  const { website: website_uuid, hostname, screen, language, cache } = payload;
+
+  if (cache) {
+    const result = await parseToken(cache);
+
+    if (result) {
+      return result;
+    }
+  }
 
   if (!isValidUuid(website_uuid)) {
     throw new Error(`Invalid website: ${website_uuid}`);