Do not flood keys with same value in meta in sessionStorageCache an…

…d `localStorageCache`

.changeset/sweet-eels-watch.md

@@ -0,0 +1,5 @@
+---
+'@farfetched/core': patch
+---
+
+Do not flood keys with same value in meta in `sessionStorageCache` and `localStorageCache`

packages/core/src/cache/adapters/__test__/local_storage.test.ts

@@ -5,6 +5,7 @@
 import { createEvent, fork, scopeBind } from 'effector';
 import { describe, beforeEach, test, expect, vi } from 'vitest';
 
+import { META_KEY } from '../browser_storage';
 import { localStorageCache } from '../local_storage';
 
 describe('localStorageCache', () => {
@@ -53,4 +54,22 @@ describe('localStorageCache', () => {
     expect(listener).toBeCalledTimes(1);
     expect(listener).toBeCalledWith({ key: 'key' });
   });
+
+  test('do not flood keys with same value in meta', async () => {
+    const cache = localStorageCache();
+
+    const scope = fork();
+
+    await scopeBind(cache.set, {
+      scope,
+    })({ key: 'key', value: 'myValue' });
+
+    await scopeBind(cache.set, {
+      scope,
+    })({ key: 'key', value: 'myValue' });
+
+    expect(JSON.parse(localStorage.getItem(META_KEY)!)).toEqual({
+      keys: ['key'],
+    });
+  });
 });

packages/core/src/cache/adapters/__test__/session_storage.test.ts

@@ -5,6 +5,7 @@
 import { createEvent, fork, scopeBind } from 'effector';
 import { describe, beforeEach, test, expect, vi } from 'vitest';
 
+import { META_KEY } from '../browser_storage';
 import { sessionStorageCache } from '../session_storage';
 
 describe('sessionStorageCache', () => {
@@ -53,4 +54,22 @@ describe('sessionStorageCache', () => {
     expect(listener).toBeCalledTimes(1);
     expect(listener).toBeCalledWith({ key: 'key' });
   });
+
+  test('do not flood keys with same value in meta', async () => {
+    const cache = sessionStorageCache();
+
+    const scope = fork();
+
+    await scopeBind(cache.set, {
+      scope,
+    })({ key: 'key', value: 'myValue' });
+
+    await scopeBind(cache.set, {
+      scope,
+    })({ key: 'key', value: 'myValue' });
+
+    expect(JSON.parse(sessionStorage.getItem(META_KEY)!)).toEqual({
+      keys: ['key'],
+    });
+  });
 });

packages/core/src/cache/adapters/browser_storage.ts

@@ -7,6 +7,8 @@ import { attachObservability } from './observability';
 import { CacheAdapter, CacheAdapterOptions } from './type';
 import { get } from '../../libs/lohyphen';
 
+export const META_KEY = '__farfetched_meta__';
+
 export function browserStorageCache(
   config: {
     storage: () => Storage;
@@ -132,8 +134,6 @@ export function browserStorageCache(
   }
 
   // -- meta storage
-  const META_KEY = '__farfetched_meta__';
-
   const $meta = createStore<Meta | null>(null, { serialize: 'ignore' });
 
   const getMetaFx = createEffect(async () => {
@@ -168,7 +168,15 @@ export function browserStorageCache(
   sample({
     clock: addKey,
     source: $meta,
-    fn: (meta, { key }) => ({ ...meta, keys: [...(meta?.keys ?? []), key] }),
+    fn: (meta, { key }) => {
+      const knownKeys = meta?.keys ?? [];
+
+      if (knownKeys.includes(key)) {
+        return meta;
+      }
+
+      return { ...meta, keys: [...knownKeys, key] };
+    },
     target: $meta,
   });
   sample({