From: Eduardo San Martin Morote <posva13@gmail.com>
Date: Wed, 12 May 2021 14:55:49 +0000 (+0200)
Subject: docs: note about subscribe in plugins
X-Git-Tag: v2.0.0-alpha.17~21
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=26a1fe3f9c16d1b26e6972b9626ba309c98d483c;p=thirdparty%2Fvuejs%2Fpinia.git

docs: note about subscribe in plugins
---

diff --git a/docs/core-concepts/plugins.md b/docs/core-concepts/plugins.md
index 3d66453f..a9623375 100644
--- a/docs/core-concepts/plugins.md
+++ b/docs/core-concepts/plugins.md
@@ -73,6 +73,24 @@ pinia.use(({ store }) => {
 
 This is why you can access all computed properties without `.value`.
 
+## `$subscribe` inside plugins
+
+Because of the limitation mentioned above about plugins being invoked **every time `useStore()` is called**, it's important to avoid _subscribing_ multiple times by keeping track of the registered subscriptions:
+
+```ts
+let isRegistered
+pinia.use({ store }) => {
+  if (!isRegistered) {
+  store.$subscribe(() => {
+    // react to store changes
+  })
+  isRegistered = true
+  }
+})
+```
+
+The same is true for `store.$onAction()`.
+
 ## Adding new options
 
 It is possible to create new options when defining stores to later on consume the options on plugins. For example, you could create a `debounce` option that allows you to debounce any action: