chore(storage-key): fetch storage key and invalidate storage on mismatch

frontend/src/lib/storage-manager/storage-manager.js

@@ -2,6 +2,8 @@
 
 import * as semver from 'semver';
 
+import { HttpClient } from '../../services/http-client/http-client';
+
 export const LOCATION = {
   LOCAL: 'local',
   SESSION: 'session',
@@ -38,6 +40,30 @@ export class StorageManager {
       this._global = window;
     else
       throw new Error('Cannot setup StorageManager without window or global');
+    
+    if (this._options.encryption) {
+      const requestBody = {
+        type   : this._options.encryption,
+        length : 42,
+        ...this.load('encryption'),
+      };
+      this._global.App.httpClient.post({
+        url: '../../../../../../user/storage-key',  // TODO use APPROOT instead
+        headers: {
+          'Content-Type' : HttpClient.ACCEPT.JSON,
+          'Accept'       : HttpClient.ACCEPT.JSON,
+        },
+        body: JSON.stringify(requestBody),
+      }).then(
+        (response) => response.json()
+      ).then((response) => {
+        console.log('storage-manager got key from response:', response);
+        if (response.salt !== requestBody.salt || response.timestamp !== requestBody.timestamp) {
+          this.clear();
+        }
+        this.save('encryption', response);
+      }).catch(console.error);
+    }
   }
 
   save(key, value, options=this._options) {