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Auto-imports | Nuxt auto-imports components, composables, helper functions and Vue APIs. |
Nuxt auto-imports components, composables and Vue.js APIs to use across your application without explicitly importing them.
<script setup lang="ts">
const count = ref(1) // ref is auto-imported
</script>
Thanks to its opiniated directory structure, Nuxt can auto-import your components/
, composables/
and utils/
.
Contrary to a classic global declaration, Nuxt preserves typings, IDEs completions and hints, and only includes what is used in your production code.
::callout{color="blue" icon="i-ph-lightbulb-duotone"} In the docs, every function that is not explicitly imported is auto-imported by Nuxt and can be used as-is in your code. You can find a reference for auto-imported components, composables and utilities in the API section. ::
::callout
In the server
directory, Nuxt auto-imports exported functions and variables from server/utils/
.
::
::callout
You can also auto-import functions exported from custom folders or third-party packages by configuring the imports
section of your nuxt.config
file.
::
Built-in Auto-imports
Nuxt auto-imports functions and composables to perform data fetching, get access to the app context and runtime config, manage state or define components and plugins.
<script setup lang="ts">
/* useAsyncData() and $fetch() are auto-imported */
const { data, refresh, pending } = await useFetch('/api/hello')
</script>
Vue 3 exposes Reactivity APIs like ref
or computed
, as well as lifecycle hooks and helpers that are auto-imported by Nuxt.
<script setup lang="ts">
/* ref() and computed() are auto-imported */
const count = ref(1)
const double = computed(() => count.value * 2)
</script>
Vue and Nuxt composables
When you are using the built-in Composition API composables provided by Vue and Nuxt, be aware that many of them rely on being called in the right context.
During a component lifecycle, Vue tracks the temporary instance of the current component (and similarly, Nuxt tracks a temporary instance of nuxtApp
) via a global variable, and then unsets it in same tick. This is essential when server rendering, both to avoid cross-request state pollution (leaking a shared reference between two users) and to avoid leakage between different components.
That means that (with very few exceptions) you cannot use them outside a Nuxt plugin, Nuxt route middleware or Vue setup function. On top of that, you must use them synchronously - that is, you cannot use await
before calling a composable, except within <script setup>
blocks, within the setup function of a component declared with defineNuxtComponent
, in defineNuxtPlugin
or in defineNuxtRouteMiddleware
, where we perform a transform to keep the synchronous context even after the await
.
If you get an error message like Nuxt instance is unavailable
then it probably means you are calling a Nuxt composable in the wrong place in the Vue or Nuxt lifecycle.
::read-more{to="/docs/guide/going-further/experimental-features#asynccontext" icon="i-ph-star-duotone"}
Checkout the asyncContext
experimental feature to use Nuxt composables in async functions.
::
::read-more{to="https://github.com/nuxt/nuxt/issues/14269#issuecomment-1397352832" target="_blank"} See the full explanation in this GitHub comment. ::
Example of breaking code:
// trying to access runtime config outside a composable
const config = useRuntimeConfig()
export const useMyComposable = () => {
// accessing runtime config here
}
Example of working code:
export const useMyComposable = () => {
// Because your composable is called in the right place in the lifecycle,
// useRuntimeConfig will also work
const config = useRuntimeConfig()
// ...
}
Directory-based Auto-imports
Nuxt directly auto-imports files created in defined directories:
components/
for Vue components.composables/
for Vue composables.utils/
for helper functions and other utilities.
:link-example{to="/docs/examples/features/auto-imports"}
Explicit Imports
Nuxt exposes every auto-import with the #imports
alias that can be used to make the import explicit if needed:
<script setup lang="ts">
import { ref, computed } from '#imports'
const count = ref(1)
const double = computed(() => count.value * 2)
</script>
Disabling Auto-imports
If you want to disable auto-importing composables and utilities, you can set imports.autoImport
to false
in the nuxt.config
file.
export default defineNuxtConfig({
imports: {
autoImport: false
}
})
This will disable auto-imports completely but it's still possible to use explicit imports from #imports
.
Auto-imported Components
Nuxt also automatically imports components from your ~/components
directory, although this is configured separately from auto-importing composables and utility functions.
:read-more{to="/docs/guide/directory-structure/components"}
To disable auto-importing components from your own ~/components
directory, you can set components.dirs
to an empty array (though note that this will not affect components added by modules).
export default defineNuxtConfig({
components: {
dirs: []
}
})
Auto-import from third-party packages
Nuxt also allows auto-importing from third-party packages.
::callout If you are using the Nuxt module for that package, it is likely that the module has already configured auto-imports for that package. ::
For example, you could enable the auto-import of the useI18n
composable from the vue-i18n
package like this:
export default defineNuxtConfig({
imports: {
presets: [
{
from: 'vue-i18n',
imports: ['useI18n']
}
]
}
})