From f077d300bf49f812c78a8abc9871f64822b9ae83 Mon Sep 17 00:00:00 2001
From: Gautam Kachru <gkachru@users.noreply.github.com>
Date: Wed, 2 Oct 2024 02:52:58 +0530
Subject: [PATCH] Fix: Issue of synchronizing namespaced local memory caches
 (#37)

---
 .../bentocache/src/cache/stack/cache_stack.ts | 25 +++++----
 packages/bentocache/tests/bus/bus.spec.ts     | 56 +++++++++++++++++++
 2 files changed, 70 insertions(+), 11 deletions(-)

diff --git a/packages/bentocache/src/cache/stack/cache_stack.ts b/packages/bentocache/src/cache/stack/cache_stack.ts
index dd16dc9..c190b31 100644
--- a/packages/bentocache/src/cache/stack/cache_stack.ts
+++ b/packages/bentocache/src/cache/stack/cache_stack.ts
@@ -20,6 +20,8 @@ export class CacheStack {
   l1?: LocalCache
   l2?: RemoteCache
   bus?: Bus
+  #busDriver?: BusDriver
+  #busOptions?: BusOptions
   defaultOptions: CacheEntryOptions
   logger: Logger
 
@@ -46,22 +48,23 @@ export class CacheStack {
     if (bus) return bus
     if (!busDriver || !this.l1) return
 
-    const opts = lodash.merge({ retryQueue: { enabled: true, maxSize: undefined } }, busOptions)
-    const newBus = new Bus(busDriver, this.l1, this.logger, this.emitter, opts)
+    this.#busDriver = busDriver
+    this.#busOptions = lodash.merge(
+      { retryQueue: { enabled: true, maxSize: undefined } },
+      busOptions,
+    )
+    const newBus = new Bus(this.#busDriver, this.l1, this.logger, this.emitter, this.#busOptions)
 
     return newBus
   }
 
   namespace(namespace: string) {
-    return new CacheStack(
-      this.name,
-      this.options,
-      {
-        l1Driver: this.l1?.namespace(namespace),
-        l2Driver: this.l2?.namespace(namespace),
-      },
-      this.bus,
-    )
+    return new CacheStack(this.name, this.options, {
+      l1Driver: this.l1?.namespace(namespace),
+      l2Driver: this.l2?.namespace(namespace),
+      busDriver: this.#busDriver,
+      busOptions: this.#busOptions,
+    })
   }
 
   emit(event: CacheEvent) {
diff --git a/packages/bentocache/tests/bus/bus.spec.ts b/packages/bentocache/tests/bus/bus.spec.ts
index c12c089..0d9df72 100644
--- a/packages/bentocache/tests/bus/bus.spec.ts
+++ b/packages/bentocache/tests/bus/bus.spec.ts
@@ -33,6 +33,62 @@ test.group('Bus synchronization', () => {
     assert.isUndefined(await cache3.get(key))
   }).disableTimeout()
 
+  test('synchronize multiple cache with a namespace', async ({ assert }) => {
+    const key = 'foo'
+
+    const [cache1] = new CacheFactory().withL1L2Config().create()
+    const [cache2] = new CacheFactory().withL1L2Config().create()
+    const [cache3] = new CacheFactory().withL1L2Config().create()
+
+    await cache1.namespace('users').set(key, 24)
+    await setTimeout(100)
+
+    assert.equal(await cache1.namespace('users').get(key), 24)
+    assert.equal(await cache2.namespace('users').get(key), 24)
+    assert.equal(await cache3.namespace('users').get(key), 24)
+
+    await cache1.namespace('users').delete(key)
+
+    await setTimeout(100)
+
+    assert.isUndefined(await cache1.namespace('users').get(key))
+    assert.isUndefined(await cache2.namespace('users').get(key))
+    assert.isUndefined(await cache3.namespace('users').get(key))
+  }).disableTimeout()
+
+  test('synchronize multiple cache with multiple namespaces', async ({ assert }) => {
+    const key = 'bar'
+
+    const [cache1] = new CacheFactory().withL1L2Config().create()
+    const [cache2] = new CacheFactory().withL1L2Config().create()
+    const [cache3] = new CacheFactory().withL1L2Config().create()
+
+    const cache1NSUsersMe = cache1.namespace('users').namespace('me')
+    const cache2NSUsersMe = cache2.namespace('users').namespace('me')
+    const cache3NSAdmin = cache3.namespace('admin')
+
+    await cache1NSUsersMe.set(key, 24)
+    await cache3NSAdmin.set(key, 42)
+    await setTimeout(100)
+
+    assert.equal(await cache1NSUsersMe.get(key), 24)
+    assert.equal(await cache2NSUsersMe.get(key), 24)
+    assert.equal(await cache3NSAdmin.get(key), 42)
+
+    await cache1NSUsersMe.clear()
+
+    await setTimeout(100)
+
+    assert.isUndefined(await cache1NSUsersMe.get(key))
+    assert.isUndefined(await cache2.namespace('users').namespace('me').get(key))
+    assert.equal(await cache3NSAdmin.get(key), 42)
+
+    await cache2.namespace('admin').clear()
+    await setTimeout(100)
+
+    assert.isUndefined(await cache3NSAdmin.get(key))
+  }).disableTimeout()
+
   test('retry queue processing', async ({ assert }) => {
     const bus1 = new ChaosBus(new MemoryTransport())
     const bus2 = new ChaosBus(new MemoryTransport())