bump to commons 3.0.6; add LocalStorageBackedAsyncStore (FF-1980) (#62)

* bump to commons 3.0.6; add LocalStorageBackedAsyncStore (FF-1980)

* remove comment

Author: leoromanovsky

package.json

@@ -57,7 +57,7 @@
     "webpack-cli": "^4.10.0"
   },
   "dependencies": {
-    "@eppo/js-client-sdk-common": "3.0.2",
+    "@eppo/js-client-sdk-common": "3.0.6",
     "md5": "^2.3.0"
   }
 }

src/configuration-factory.ts

@@ -0,0 +1,30 @@
+import {
+  Flag,
+  HybridConfigurationStore,
+  IConfigurationStore,
+  MemoryOnlyConfigurationStore,
+  MemoryStore,
+} from '@eppo/js-client-sdk-common';
+
+import { LocalStorageBackedAsyncStore } from './local-storage';
+
+export function configurationStorageFactory(): IConfigurationStore<Flag> {
+  if (hasWindowLocalStorage()) {
+    // fallback to window.localStorage if available
+    return new HybridConfigurationStore(
+      new MemoryStore<Flag>(),
+      new LocalStorageBackedAsyncStore<Flag>(window.localStorage),
+    );
+  }
+
+  return new MemoryOnlyConfigurationStore();
+}
+
+export function hasWindowLocalStorage(): boolean {
+  try {
+    return typeof window !== 'undefined' && !!window.localStorage;
+  } catch {
+    // Chrome throws an error if local storage is disabled and you try to access it
+    return false;
+  }
+}