store
The store
directory contains your Vuex Store files. The Vuex Store comes with Nuxt.js out of the box but is disabled by default. Creating an index.js
file in this directory enables the store.
This directory cannot be renamed without extra configuration.
Using a store to manage the state is important for every big application. That's why Nuxt.js implements Vuex in its core.
Activate the Store
Nuxt.js will look for the store
directory, if it exists, it will:
- Import Vuex
- Add the
store
option to the root Vue instance.
Modules
Every .js
file inside the store
directory is transformed as a namespaced module (index
being the root module). Your state
value should always be a function
to avoid unwanted shared state on the server side.
To get started, export the state as a function, and the mutations and actions as objects.
export const state = () => ({
counter: 0
})
export const mutations = {
increment(state) {
state.counter++
}
}
Then, you can have a store/todos.js
file:
export const state = () => ({
list: []
})
export const mutations = {
add(state, text) {
state.list.push({
text,
done: false
})
},
remove(state, { todo }) {
state.list.splice(state.list.indexOf(todo), 1)
},
toggle(todo) {
todo.done = !todo.done
}
}
The store will be created as such:
new Vuex.Store({
state: () => ({
counter: 0
}),
mutations: {
increment(state) {
state.counter++
}
},
modules: {
todos: {
namespaced: true,
state: () => ({
list: []
}),
mutations: {
add(state, { text }) {
state.list.push({
text,
done: false
})
},
remove(state, { todo }) {
state.list.splice(state.list.indexOf(todo), 1)
},
toggle(state, { todo }) {
todo.done = !todo.done
}
}
}
}
})
And in your pages/todos.vue
, using the todos
module:
<template>
<ul>
<li v-for="todo in todos" :key="todo.text">
<input :checked="todo.done" @change="toggle(todo)" type="checkbox">
<span :class="{ done: todo.done }">{{ todo.text }}</span>
</li>
<li><input @keyup.enter="addTodo" placeholder="What needs to be done?"></li>
</ul>
</template>
<script>
import { mapMutations } from 'vuex'
export default {
computed: {
todos () {
return this.$store.state.todos.list
}
},
methods: {
addTodo (e) {
this.$store.commit('todos/add', e.target.value)
e.target.value = ''
},
...mapMutations({
toggle: 'todos/toggle'
})
}
}
</script>
<style>
.done {
text-decoration: line-through;
}
</style>
The module method also works for top-level definitions without implementing a sub-directory in the store directory.
Example for state: you create a file store/state.js
and add the following.
export default () => ({
counter: 0
})
And the corresponding mutations can be in the file store/mutations.js
export default {
increment(state) {
state.counter++
}
}
Plugins in the Store
You can add additional plugins to the store by putting them into the store/index.js
file:
import myPlugin from 'myPlugin'
export const plugins = [myPlugin]
export const state = () => ({
counter: 0
})
export const mutations = {
increment(state) {
state.counter++
}
}
More information about the plugins: Vuex documentation.
The nuxtServerInit Action
If the action nuxtServerInit
is defined in the store and the mode is universal
, Nuxt.js will call it with the context (only from the server-side). It's useful when we have some data on the server we want to give directly to the client-side.
For example, let's say we have sessions on the server-side and we can access the connected user through req.session.user
. To give the authenticated user to our store, we update our store/index.js
to the following:
actions: {
nuxtServerInit ({ commit }, { req }) {
if (req.session.user) {
commit('user', req.session.user)
}
}
}
Only the primary module (in store/index.js
) will receive this action. You'll need to chain your module actions from there.
The context is given to nuxtServerInit
as the 2nd argument in the asyncData
method.
If nuxt generate
is ran, nuxtServerInit
will be executed for every dynamic route generated.
Asynchronous nuxtServerInit
actions must return a Promise or leverage async/await to allow the nuxt server to wait on them.
actions: {
async nuxtServerInit({ dispatch }) {
await dispatch('core/load')
}
}
Vuex Strict Mode
Strict mode is enabled by default on dev mode and turned off in production mode. To disable strict mode in dev, follow the below example in store/index.js
:
export const strict = false