docs: add more context about mode in call-once composable

This commit is contained in:
Saeid Zareie 2025-01-15 18:55:47 +03:30
parent c780a6e2e2
commit c699189f77

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@ -14,6 +14,10 @@ links:
This utility is available since [Nuxt v3.9](/blog/v3-9).
::
::important
`navigation` mode is available since [Nuxt v3.15](/blog/v3-15).
::
## Purpose
The `callOnce` function is designed to execute a given function or block of code only once during:
@ -24,6 +28,8 @@ This is useful for code that should be executed only once, such as logging an ev
## Usage
Running code only once. For example, if the code runs on the server it won't run again on the client.
```vue [app.vue]
<script setup lang="ts">
const websiteConfig = useState('config')
@ -35,6 +41,19 @@ await callOnce(async () => {
</script>
```
Sometimes you do want code to run on every navigation - just avoid the initial server/client double load. For this, there's a new mode: 'navigation' option that will run the code only once per navigation.
```vue [app.vue]
<script setup lang="ts">
const websiteConfig = useState('config')
await callOnce(async () => {
console.log('This will only be logged once and then on every client side navigation')
websiteConfig.value = await $fetch('https://my-cms.com/api/website-config')
}, { mode: 'navigation' })
</script>
```
::tip{to="/docs/getting-started/state-management#usage-with-pinia"}
`callOnce` is useful in combination with the [Pinia module](/modules/pinia) to call store actions.
::
@ -52,9 +71,11 @@ Note that `callOnce` doesn't return anything. You should use [`useAsyncData`](/d
## Type
```ts
callOnce(fn?: () => any | Promise<any>): Promise<void>
callOnce(key: string, fn?: () => any | Promise<any>): Promise<void>
callOnce (key?: string, fn?: (() => any | Promise<any>), options?: CallOnceOptions): Promise<void>
callOnce(fn?: (() => any | Promise<any>), options?: CallOnceOptions): Promise<void>
```
## Parameters
- `key`: A unique key ensuring that the code is run once. If you do not provide a key, then a key that is unique to the file and line number of the instance of `callOnce` will be generated for you.
- `fn`: The function to run once. This function can also return a `Promise` and a value.
* `key`: A unique key ensuring that the code is run once. If you do not provide a key, then a key that is unique to the file and line number of the instance of `callOnce` will be generated for you.
* `fn`: The function to run once. This function can also return a `Promise` and a value.
* `options`: Setup the mode, either to re-execute on navigation (`navigation`) or just once for lifetime of the app (`render`)