Pass State to Nuxt and Populate Pinia Store

A common scenario is to fetch data from an API during the build process and pass it to Nuxt. This can be done with the #nuxt-prepare context.

With returning a state object in your defineNuxtPrepareHandler handler, you can pass data to Nuxt and import it anywhere from #nuxt-prepare.

One use case is to populate an app store like Pinia with the data that is pre-fetched during the build process. To do this, first create a store.prepare.ts file and define a defineNuxtPrepareHandler handler. Inside the handler, fetch the data from an API and return it in the state object:

// `store.prepare.ts`
import { ofetch } from 'ofetch'
import type { FetchError } from 'ofetch'
import { defineNuxtPrepareHandler } from 'nuxt-prepare/config'

export default defineNuxtPrepareHandler(async () => {
  let todos: Record<string, unknown> | undefined
  let error: FetchError | undefined

  try {
    todos = await ofetch('todos/1', {
      baseURL: 'https://jsonplaceholder.typicode.com',
    })
  }
  catch (err) {
    error = err as FetchError
    console.error(error)
  }

  return {
    // If the fetch failed, we want to halt the build
    ok: !error,

    // Pass your todos data to Nuxt and import it
    // anywhere from `#nuxt-prepare`
    state: {
      todos
    }
  }
})

Once the fetch request succeeds, the todos data is be available from the #nuxt-prepare context:

// `stores/todo.ts`
import { defineStore } from 'pinia'
import { todos } from '#nuxt-prepare'

export const useTodos = defineStore('todos', {
  state: () => ({
    todos: todos || []
  })
})