What is Vue Query?
Vue Query provides hooks for fetching, caching and updating asynchronous data in Vue.
It is based on React Query and inherits all of its concepts from the main package.
It works in both Vue 2 with the Composition API plugin and Vue 3.
Installing Vue Query
To install Vue Query, we run the following command in a terminal:
yarn add vue-query
Using Vue Query
Vue Query requires a query provider attached in the root of our application.
import { defineComponent } from 'vue';
import { useQueryProvider } from 'vue-query';
export default defineComponent({
name: 'App',
setup() {
useQueryProvider();
},
});
useQueryProvider provides our app an instance of the QueryClient class from the react-query/core package.
In a component that fetches data, a useQuery hook allows us to specify our function that fetches data:
import { defineComponent } from 'vue'
import { useQuery } from 'vue-query';
...
export default defineComponent({
name: 'Todos',
setup() {
const { data, isLoading, isError } = useQuery(
'todos', // query key
getTodos // fetching function
)
return {
data,
isLoading,
isError
}
}
})
As you can see with useQuery the first argument is a simple string. This caches and tracks the result of that query.
The second argument is how we actually get the data. It either needs to resolve data or throw an error.
useQuery has generic parameters for the type of the data that is being fetched and the error type if a failure occurs:
useQuery<Todo[], Error>(
'todos',
getTodos
);
Error is the standard error object.
The Todo type is as follows:
type Todo = {
userId: number
id: number
title: string
completed: boolean
}
Fetching function
The fetching function implementation is as follows:
async function getTodos() {
const response = await fetch('https://jsonplaceholder.typicode.com/');
return response.json();
}
Finishing the component
Here’s the rest of the component implementation:
<template>
<div v-if="isLoading">Loading...</div>
<div v-else-if="isError">{{ error!.message }}</div>
<div v-else>{{ JSON.stringify(data) }}</div>
</template>
<script lang="ts">
import { defineComponent } from 'vue'
import { useQuery } from 'vue-query'
type Todo = {
userId: number
id: number
title: string
completed: boolean
}
export default defineComponent({
name: 'Todos',
setup() {
const { data, isLoading, isError, error } = useQuery<Todo[], Error>(
'todos',
getTodos
)
return {
data,
isLoading,
isError,
error
}
}
})
</script>
After the first request, the response will be instant because we're using cached data.
If you’re interested to learn more, don’t forget to check out the Vue Query documentation and the React Query documentation.
Top comments (0)