Nuxt/docs/3.api/3.utils/$fetch.md

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$fetch Nuxt uses ofetch to expose globally the $fetch helper for making HTTP requests.
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Source i-simple-icons-github https://github.com/nuxt/nuxt/blob/main/packages/nuxt/src/app/entry.ts xs

Nuxt uses ofetch to expose globally the $fetch helper for making HTTP requests within your Vue app or API routes.

::tip{icon="i-ph-rocket-launch" color="gray"} During server-side rendering, calling $fetch to fetch your internal API routes will directly call the relevant function (emulating the request), saving an additional API call. ::

::note{color="blue" icon="i-ph-info"} Using $fetch in components without wrapping it with useAsyncData causes fetching the data twice: initially on the server, then again on the client-side during hydration, because $fetch does not transfer state from the server to the client. Thus, the fetch will be executed on both sides because the client has to get the data again. ::

Usage

We recommend to use useFetch or useAsyncData + $fetch to prevent double data fetching when fetching the component data.

<script setup lang="ts">
// During SSR data is fetched twice, once on the server and once on the client.
const dataTwice = await $fetch('/api/item')

// During SSR data is fetched only on the server side and transferred to the client.
const { data } = await useAsyncData('item', () => $fetch('/api/item'))

// You can also useFetch as shortcut of useAsyncData + $fetch
const { data } = await useFetch('/api/item')
</script>

:read-more{to="/docs/getting-started/data-fetching"}

You can use $fetch in any methods that are executed only on client-side.

<script setup lang="ts">
function contactForm() {
  $fetch('/api/contact', {
    method: 'POST',
    body: { hello: 'world '}
  })
}
</script>

<template>
  <button @click="contactForm">Contact</button>
</template>

::tip $fetch is the preferred way to make HTTP calls in Nuxt instead of @nuxt/http and @nuxtjs/axios that are made for Nuxt 2. ::

::note If you use $fetch to call an (external) HTTPS URL with a self-signed certificate in development, you will need to set NODE_TLS_REJECT_UNAUTHORIZED=0 in your environment. ::

Passing Headers and Cookies

When we call $fetch in the browser, user headers like cookie will be directly sent to the API.

However, during Server-Side Rendering, due to security risks such as Server-Side Request Forgery (SSRF) or Authentication Misuse, the $fetch wouldn't include the user's browser cookies, nor pass on cookies from the fetch response.

::code-group

<script setup lang="ts">
// This will NOT forward headers or cookies during SSR
const { data } = await useAsyncData(() => $fetch('/api/cookies'))
</script>
export default defineEventHandler((event) => {
  const foo = getCookie(event, 'foo')
  // ... Do something with the cookie
})

::

If you need to forward headers and cookies on the server, you must manually pass them:

<script setup lang="ts">
// This will forward the user's headers and cookies to `/api/cookies`
const requestFetch = useRequestFetch()
const { data } = await useAsyncData(() => requestFetch('/api/cookies'))
</script>

However, when calling useFetch with a relative URL on the server, Nuxt will use useRequestFetch to proxy headers and cookies (with the exception of headers not meant to be forwarded, like host).