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Lukas Borawski
Lukas Borawski

Posted on • Updated on

Nuxt asyncData recall.

Short disclaimer at the beginning - this one might be not valid anymore soon because the Nuxt 3.0 is just right behind the corner. Along with it, we will get a new, fresh, and shiny useFetch API. Recreated with Composition API it will change the whole process of fetching data across our Nuxt apps.

A simple example will look like:

import { useFetch } from '@nuxt/composables'

export default {
  async setup() {
    const { data: posts } = await useFetch('https://your.api.url')
    return posts
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Sexy, I know. 😆

But since it's not public and not quite official at that very moment we still using the 2.x version of the framework and we still lay our apps on the existing API. According to that, this might be helpful for some of you.

As we all know for various cases of data fetching we can use the fetch() hook with $fetchState object which contains pending and error values. It also can be recalled with this.$fetch method. For others when we need our data just before the page render we have to use asyncData. One problem with asyncData is that we can't call it again - for example on route change action. What we can do about it then?

Firstly define your fetch function outside the regular component.

async fetch() {
  const { posts } = await forApiResponse()
  return {
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Then inside the asyncData hook use this function.

asyncData() {
  return fetch()  
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Recall it while watching some route changes.

data: () => ({
  posts: []  
watch: {
  $route() {
    const data = fetch()
    Object.assign(this.$data, data)
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To avoid data conflicts we might want to reset it to the default state before fetching it again. Maybe this one is not so elegant as the fancy fetch() API but that way we can get our data before the page renders and react to it. Displaying a 404 error for example - very valuable from SEO perspective.

And this is it. Enjoy.

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