Settings as clean architecture

src/background/repositories/setting.js

@@ -0,0 +1,17 @@
+import MemoryStorage from '../infrastructures/memory-storage';
+
+const CACHED_SETTING_KEY = 'setting';
+
+export default class SettingRepository {
+  constructor() {
+    this.cache = new MemoryStorage();
+  }
+
+  get() {
+    return Promise.resolve(this.cache.get(CACHED_SETTING_KEY));
+  }
+
+  update(value) {
+    return this.cache.set(CACHED_SETTING_KEY, value);
+  }
+}