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Error handling
Learn how to catch errors in different lifecycle.
Handling Errors
Nuxt 3 is a full-stack framework, which means there are several sources of unpreventable user runtime errors that can happen in different contexts:
- Errors during the Vue rendering lifecycle (SSR + SPA)
- Errors during API or Nitro server lifecycle
- Server and client startup errors (SSR + SPA)
- Errors downloading JS chunks
Errors During the Vue Rendering Lifecycle (SSR + SPA)
You can hook into Vue errors using onErrorCaptured
.
In addition, Nuxt provides a vue:error
hook that will be called if any errors propagate up to the top level.
If you are using an error reporting framework, you can provide a global handler through vueApp.config.errorHandler
. It will receive all Vue errors, even if they are handled.
Example With Global Error Reporting Framework
export default defineNuxtPlugin((nuxtApp) => {
nuxtApp.vueApp.config.errorHandler = (error, context) => {
// ...
}
})
Server and Client Startup Errors (SSR + SPA)
Nuxt will call the app:error
hook if there are any errors in starting your Nuxt application.
This includes:
- running Nuxt plugins
- processing
app:created
andapp:beforeMount
hooks - rendering your Vue app to HTML (on the server)
- mounting the app (on client-side), though you should handle this case with
onErrorCaptured
or withvue:error
- processing the
app:mounted
hook
Errors During API or Nitro Server Lifecycle
You cannot currently define a server-side handler for these errors, but can render an error page (see the next section).
Errors downloading JS chunks
You might encounter chunk loading errors due to a network connectivity failure or a new deployment (which invalidates your old, hashed JS chunk URLs). Nuxt provides built-in support for handling chunk loading errors by performing a hard reload when a chunk fails to load during route navigation.
You can change this behavior by setting experimental.emitRouteChunkError
to false
(to disable hooking into these errors at all) or to manual
if you want to handle them yourself. If you want to handle chunk loading errors manually, you can check out the the automatic implementation for ideas.
Rendering an Error Page
When Nuxt encounters a fatal error, whether during the server lifecycle, or when rendering your Vue application (both SSR and SPA), it will either render a JSON response (if requested with Accept: application/json
header) or an HTML error page.
You can customize this error page by adding ~/error.vue
in the source directory of your application, alongside app.vue
. This page has a single prop - error
which contains an error for you to handle.
When you are ready to remove the error page, you can call the clearError
helper function, which takes an optional path to redirect to (for example, if you want to navigate to a 'safe' page).
::alert{type="warning"}
Make sure to check before using anything dependent on Nuxt plugins, such as $route
or useRouter
, as if a plugin threw an error, then it won't be re-run until you clear the error.
::
::alert{type="warning"} If you are running on Node 16 and you set any cookies when rendering your error page, they will overwrite cookies previously set. We recommend using a newer version of Node as Node 16 will reach end-of-life in September 2023. ::
Example
<script setup lang="ts">
const props = defineProps({
error: Object
})
const handleError = () => clearError({ redirect: '/' })
</script>
<template>
<button @click="handleError">Clear errors</button>
</template>
Error Helper Methods
useError
function useError (): Ref<Error | { url, statusCode, statusMessage, message, description, data }>
This function will return the global Nuxt error that is being handled.
::ReadMore{link="/docs/api/composables/use-error"} ::
createError
function createError (err: { cause, data, message, name, stack, statusCode, statusMessage, fatal }): Error
You can use this function to create an error object with additional metadata. It is usable in both the Vue and Nitro portions of your app, and is meant to be thrown.
If you throw an error created with createError
:
- on server-side, it will trigger a full-screen error page which you can clear with
clearError
. - on client-side, it will throw a non-fatal error for you to handle. If you need to trigger a full-screen error page, then you can do this by setting
fatal: true
.
Example
<script setup lang="ts">
const route = useRoute()
const { data } = await useFetch(`/api/movies/${route.params.slug}`)
if (!data.value) {
throw createError({ statusCode: 404, statusMessage: 'Page Not Found' })
}
</script>
showError
function showError (err: string | Error | { statusCode, statusMessage }): Error
You can call this function at any point on client-side, or (on server side) directly within middleware, plugins or setup()
functions. It will trigger a full-screen error page which you can clear with clearError
.
It is recommended instead to use throw createError()
.
::ReadMore{link="/docs/api/utils/show-error"} ::
clearError
function clearError (options?: { redirect?: string }): Promise<void>
This function will clear the currently handled Nuxt error. It also takes an optional path to redirect to (for example, if you want to navigate to a 'safe' page).
::ReadMore{link="/docs/api/utils/clear-error"} ::
Rendering Errors Within Your App
Nuxt also provides a <NuxtErrorBoundary>
component that allows you to handle client-side errors within your app, without replacing your entire site with an error page.
This component is responsible for handling errors that occur within its default slot. On client-side, it will prevent the error from bubbling up to the top level, and will render the #error
slot instead.
The #error
slot will receive error
as a prop. (If you set error = null
it will trigger re-rendering the default slot; you'll need to ensure that the error is fully resolved first or the error slot will just be rendered a second time.)
::alert{type="info"} If you navigate to another route, the error will be cleared automatically. ::
Example
<template>
<!-- some content -->
<NuxtErrorBoundary @error="someErrorLogger">
<!-- You use the default slot to render your content -->
<template #error="{ error, clearError }">
You can display the error locally here: {{ error }}
<button @click="clearError">
This will clear the error.
</button>
</template>
</NuxtErrorBoundary>
</template>
::LinkExample{link="/docs/examples/advanced/error-handling"} ::