fuel-price/.agents/skills/vueuse-functions/references/useFirestore.md

category

category
@Firebase

useFirestore

Reactive Firestore binding. Making it straightforward to always keep your local data in sync with remotes databases.

Usage

import { useFirestore } from '@vueuse/firebase/useFirestore'
import { initializeApp } from 'firebase/app'
import { collection, doc, getFirestore, limit, orderBy, query } from 'firebase/firestore'
import { computed, shallowRef } from 'vue'

const app = initializeApp({ projectId: 'MY PROJECT ID' })
const db = getFirestore(app)

const todos = useFirestore(collection(db, 'todos'))

// or for doc reference
const user = useFirestore(doc(db, 'users', 'my-user-id'))

// you can also use ref value for reactive query
const postsLimit = shallowRef(10)
const postsQuery = computed(() => query(collection(db, 'posts'), orderBy('createdAt', 'desc'), limit(postsLimit.value)))
const posts = useFirestore(postsQuery)

// you can use the boolean value to tell a query when it is ready to run
// when it gets falsy value, return the initial value
const userId = shallowRef('')
const userQuery = computed(() => userId.value && doc(db, 'users', userId.value))
const userData = useFirestore(userQuery, null)

Return Value

• For Document Reference: Returns Ref<T | null> (single document with id property)
• For Query: Returns Ref<T[]> (array of documents, each with id property)

The document id is automatically added as a read-only property to each returned document.

Options

Option	Type	Default	Description
errorHandler	(err: Error) => void	console.error	Custom error handler
autoDispose	boolean | number	true	Auto-unsubscribe on scope dispose. Pass a number for delayed dispose (ms).

Error Handling

const todos = useFirestore(collection(db, 'todos'), [], {
  errorHandler: (err) => {
    console.error('Firestore error:', err)
    // Handle error (e.g., show notification)
  },
})

Share across instances

You can reuse the db reference by passing autoDispose: false. You can also set an amount of milliseconds before auto disposing the db reference.

Note : Getting a not disposed db reference again don't cost a Firestore read.

import { useFirestore } from '@vueuse/firebase/useFirestore'
import { collection } from 'firebase/firestore'
// ---cut---
const todos = useFirestore(collection(db, 'todos'), undefined, { autoDispose: false })

or use createGlobalState from the core package

// @filename: store.ts
// ---cut---
// store.ts
import { createGlobalState } from '@vueuse/core'
import { useFirestore } from '@vueuse/firebase/useFirestore'

export const useTodos = createGlobalState(
  () => useFirestore(collection(db, 'todos')),
)

<!-- app.vue -->
<script setup lang="ts">
// @include: store
// ---cut---
import { useTodos } from './store'

const todos = useTodos()
</script>

Type Declarations

export interface UseFirestoreOptions {
  errorHandler?: (err: Error) => void
  autoDispose?: boolean | number
}
export type FirebaseDocRef<T> = Query<T> | DocumentReference<T>
type Falsy = false | 0 | "" | null | undefined
export declare function useFirestore<T extends DocumentData>(
  maybeDocRef: MaybeRef<DocumentReference<T> | Falsy>,
  initialValue: T,
  options?: UseFirestoreOptions,
): Ref<T | null>
export declare function useFirestore<T extends DocumentData>(
  maybeDocRef: MaybeRef<Query<T> | Falsy>,
  initialValue: T[],
  options?: UseFirestoreOptions,
): Ref<T[]>
export declare function useFirestore<T extends DocumentData>(
  maybeDocRef: MaybeRef<DocumentReference<T> | Falsy>,
  initialValue?: T | undefined | null,
  options?: UseFirestoreOptions,
): Ref<T | undefined | null>
export declare function useFirestore<T extends DocumentData>(
  maybeDocRef: MaybeRef<Query<T> | Falsy>,
  initialValue?: T[],
  options?: UseFirestoreOptions,
): Ref<T[] | undefined>