NuxtJS - Prevent fetch if data already exists in state? - vue.js

I have a portfolio site built using NuxtJS and a headless Wordpress CMS. On several pages, I'm importing a mixin that looks like this:
import { mapActions, mapState } from 'vuex';
export default {
computed: {
...mapState({
galleries: state => state.portfolio.galleries[0],
})
},
methods: {
...mapActions('portfolio', ['fetchGalleries']),
},
async fetch() {
await this.fetchGalleries();
}
}
The Vuex module looks like this:
export const state = () => ({
galleries: [],
});
export const actions = {
async fetchGalleries({ commit }) {
let res = await this.$axios.$get(`${process.env.WP_API_URL}/wp/v2/media`);
const data = res.reduce((acc, item) => {
const { slug } = item.acf.category;
(acc[slug] || (acc[slug] = [])).push(item);
return acc;
}, {});
commit('setGalleries', data);
}
};
export const mutations = {
setGalleries(state, data) {
state.galleries.push(data);
}
};
fetch is being used in the mixin to return data from the api before page load. I noticed however that each time I navigate to a new page, it's running that same fetch and continually adding duplicate data to Vuex state.
How do I prevent fetch from running and continually adding duplicate data to my state if it already exists?

I'm not sure why this was tripping me up so much, but I figured out a very simple solution.
async fetch() {
if (this.galleries.length) return;
await this.fetchGalleries();
}
Just added a conditional return statement as the first line within the fetch function.

Related

Using XState in Nuxt 3 with asynchronous functions

I am using XState as a state manager for a website I build in Nuxt 3.
Upon loading some states I am using some asynchronous functions outside of the state manager. This looks something like this:
import { createMachine, assign } from "xstate"
// async function
async function fetchData() {
const result = await otherThings()
return result
}
export const myMachine = createMachine({
id : 'machine',
initial: 'loading',
states: {
loading: {
invoke: {
src: async () =>
{
const result = await fetchData()
return new Promise((resolve, reject) => {
if(account != undefined){
resolve('account connected')
}else {
reject('no account connected')
}
})
},
onDone: [ target: 'otherState' ],
onError: [ target: 'loading' ]
}
}
// more stuff ...
}
})
I want to use this state machine over multiple components in Nuxt 3. So I declared it in the index page and then passed the state to the other components to work with it. Like this:
<template>
<OtherStuff :state="state" :send="send"/>
</template>
<script>
import { myMachine } from './states'
import { useMachine } from "#xstate/vue"
export default {
setup(){
const { state, send } = useMachine(myMachine)
return {state, send}
}
}
</script>
And this worked fine in the beginning. But now that I have added asynchronous functions I ran into the following problem. The states in the different components get out of sync. While they are progressing as intended in the index page (going from 'loading' to 'otherState') they just get stuck in 'loading' in the other component. And not in a loop, they simply do not progress.
How can I make sure that the states are synced in all my components?

How to Implement nuxtServerInit Action to load data from server-side on the initial load in Pinia (Nuxt3)

My Code:
export const useMenuStore = defineStore("menuStore", {
state: () => ({
menus: [],
}),
actions: {
async nuxtServerInit() {
const { body } = await fetch("https://jsonplaceholder.typicode.com/posts/1").then((response) => response.json());
console.log(body);
this.menus = body;
resolve();
},
},
});
NuxtServerInit is not working on initial page render on nuxt js vuex module mode.Anyone know this error please help me.
NuxtServerInit is not implemented in Pinia, but exists a workaround.
Using Pinia alongside Vuex
// nuxt.config.js
export default {
buildModules: [
'#nuxtjs/composition-api/module',
['#pinia/nuxt', { disableVuex: false }],
],
// ... other options
}
then Include an index.js file inside /stores with a nuxtServerInit action which will be called from the server-side on the initial load.
// store/index.js
import { useSessionStore } from '~/stores/session'
export const actions = {
async nuxtServerInit ({ dispatch }, { req, redirect, $pinia }) {
if (!req.url.includes('/auth/')) {
const store = useSessionStore($pinia)
try {
await store.me() // load user information from the server-side before rendering on client-side
} catch (e) {
redirect('/auth/login') // redirects to login if user is not logged in
}
}
}
}
In Nuxt2, the Nuxt will run the code in nuxtServerInit() of store/index.js on the server-side to boot the app.
However, in Nuxt3, there is no specific place to write the boot code, you can write the boot code anywhere instead of in nuxtServerInit() of store/index.js.
It might be helpful, especially when you need to send a request before boosting the app.
your pinia file may define like following:
store/menu.js
import { defineStore } from 'pinia';
export const useMenuStore = defineStore('menuStore', {
state: () => ({
_menus: [],
}),
getters: {
menus() {
return this._menus;
}
},
actions: {
async boot() {
const { data } = await useFetch('https://jsonplaceholder.typicode.com/posts/1');
this._menus = data;
}
}
});
Then, create a plugin which named as *.server.[ts|js], for example init.server.js
(.sever.js tail will let the file only run in server side)
plugins/init.server.js
import { defineNuxtPlugin } from '#app';
import { useMenuStore } from '~/store/menu.js';
export default defineNuxtPlugin(async (nuxtApp) => {
const menu = useMenuStore(nuxtApp.$pinia);
await menu.boot();
});
nuxt.config.js
modules: [
'#pinia/nuxt',
],
There is an entire example of SSR Nuxt3 with authorization that may help

Vue3 / Vuex State is empty when dispatching action inside of lifecycle hook inside of test

We're using the composition API with Vue 3.
We have a Vuex store that, amongst other things, stores the currentUser.
The currentUser can be null or an object { id: 'user-uuid' }.
We're using Vue Test Utils, and they've documented how to use the store inside of tests when using the Composition API. We're using the store without an injection key, and so they document to do it like so:
import { createStore } from 'vuex'
const store = createStore({
// ...
})
const wrapper = mount(App, {
global: {
provide: {
store: store
},
},
})
I have a component and before it is mounted I want to check if I have an access token and no user currently in the store.
If this is the case, we want to fetch the current user (which is an action).
This looks like so:
setup() {
const tokenService = new TokenService();
const store = useStore();
onBeforeMount(async () => {
if (tokenService.getAccessToken() && !store.state.currentUser) {
await store.dispatch(FETCH_CURRENT_USER);
console.log('User: ', store.state.currentUser);
}
});
}
I then have a test for this that looks like this:
it('should fetch the current user if there is an access token and user does not exist', async () => {
localStorage.setItem('access_token', 'le-token');
await shallowMount(App, {
global: {
provide: {
store
}
}
});
expect(store.state.currentUser).toStrictEqual({ id: 'user-uuid' });
});
The test fails, but interestingly, the console log of the currentUser in state is not empty:
console.log src/App.vue:27
User: { id: 'user-uuid' }
Error: expect(received).toStrictEqual(expected) // deep equality
Expected: {"id": "user-uuid"} Received: null
Despite the test failure, this works in the browser correctly.
Interestingly, if I extract the logic to a method on the component and then call that from within the onBeforeMount hook and use the method in my test, it passes:
setup() {
const tokenService = new TokenService();
const store = useStore();
const rehydrateUserState = async () => {
if (tokenService.getAccessToken() && !store.state.currentUser) {
await store.dispatch(FETCH_CURRENT_USER);
console.log('User: ', store.state.currentUser);
}
};
onBeforeMount(async () => {
await rehydrateUserState();
});
return {
rehydrateUserState
};
}
it('should fetch the current user if there is an access token and user does not exist', async () => {
localStorage.setItem('access_token', 'le-token');
await cmp.vm.rehydrateUserState();
expect(store.state.currentUser).toStrictEqual({ id: 'user-uuid' });
});
Any ideas on why this works when extracted to a method but not when inlined into the onBeforeMount hook?

NuxtJS dispatch is not loading data

I've been struggling for 5 hours with the following issue.
I have a service file where I have API calls using Axios. In the store, I have an action that uses the service to pull a list of schools, then I commit the data to the mutations. If I console log the data on the mutation object, it works correctly and shows the data. However, when I call dispatch from the component inside the onMounted hook, I get an empty object. Any help is greatly appreciated. (see the code below)
store/schools.js
export const state = () => ({
mySchools: []
});
export const mutations = {
getSchools(state, data) {
state.schools = data;
console.log(state.schools); // works;
}
};
export const actions = {
async getMySchools({ commit }) {
await this.$getSchools().then(response => {
commit("getSchools", response.data);
});
}
};
portal/dashboard.vue
import {onMounted, ref, useStore} from "#nuxtjs/composition-api";
export default {
layout: 'portal',
setup() {
const store = useStore();
const schools = ref([]);
onMounted(async() => {
await store.dispatch('schools/getMySchools'); // is not pulling data
schools.value = store.state.schools.mySchools;
console.log(schools); // empty
});
return {
schools
}
}
};
Thank you
You shouldn't use await with then
try this
async getMySchools({ commit }) {
const response = await this.$getSchools();
commit("getSchools", response.data);
}
I'm assuming that your this.$getSchools() actually works since I'm not sure what that is and it's not part of the code

VUEX getters returned too fast

I've a problem with getters. At first I call an action getWeather which is async:
export const actions = {
async getWeather ({commit, state}) {
try {
const locationResponse = await VueGeolocation.getLocation({ enableHighAccuracy: true });
const url = `https://api.openweathermap.org/data/2.5/weather?lat=${locationResponse.lat}&lon=${locationResponse.lng}&units=metric&appid=${process.env.apikey}`;
const response = await fetch(url);
const data = await response.json();
await commit('SET_WEATHER', data);
console.log(`DATA: ${data}`) // returns me the weather data
} catch (error) {
return console.log(error);
}
}
}
and then in my index.vue file I make this:
<script>
import { mapActions, mapGetters } from 'vuex';
export default {
beforeCreate() {
this.$store.dispatch('getWeather');
},
created() {
console.log(this.$store.getters.getWeatherInfo) // returns null
},
computed: {
...mapGetters(['getWeatherInfo'])
}
}
</script>
This returns me the null value from the state even though I mutate the state.
created() { console.log(this.$store.getters.getWeatherInfo) // returns null
Vuex mutation:
export const mutations = {
SET_WEATHER (state, payload) {
state.weather = payload;
}
}
How do I get the weather data then not null in the index.vue file ?
The reason you see null in created is because asynchronous action started in beforeCreate is not complete yet.
If you really need result of the action to be complete in created you need to to this:
async created() {
await this.$store.dispatch('getWeather');
console.log(this.$store.getters.getWeatherInfo) // now the data is in store
}
If you don't need data to be ready in created it's better to remove await and write your component template using v-if - "render this only if my getter is not null" ...it will be not-null eventually ("sometime in the future") and Vue will re-render your component...