I am aiming to have a state in my Vuex store which gets populated on initial app load with data from an external API as follows:
import axios from 'axios'
export const state = () => ({
airports: [],
pairing: {
departure: null,
arrival: null
},
loading: false
})
export const getters = {
getAirports: (state) => {
return state.airports
}
}
export const mutations = {
SET_AIRPORTS(state, payload) {
state.airports = payload
},
SET_LOADING(state, payload) {
state.loading = payload
},
SET_AIRPORT(state, { airport, type }) {
state.pairing[type] = airport
},
CLEAR_AIRPORT(state, type) {
state.pairing[type] = null
}
}
export const actions = {
loadAirports({ commit }) {
commit('SET_LOADING', true)
axios.get('https://raw.githubusercontent.com/jpatokal/openflights/master/data/airports.dat')
.then(response => {
// Get each row of data from the source
const rows = response.data.split('\n');
// Convert data from row to object
const airports = rows.map(row => {
// Parse the comma-separated fields from the line by using
const fields = row.split(',')
.map(x => x.replace(/(^"|"$)/g, ''));
return {
id: fields[0],
name: fields[1],
city: fields[2],
country: fields[3],
iata: fields[4],
icao: fields[5],
longitude: fields[6],
latitude: fields[7],
};
});
commit('SET_AIRPORTS', airports)
commit('SET_LOADING', false)
})
},
}
Usually I would just dispatch the loadAirports action in the App.vue when working with Vue.js standalone. However, as I am building my app in Nuxt.js I cannot seem to figure out how to load the data to my state without dispatching this method in every page I create but rather just once on app load.
Any suggestions?
If you have an action called nuxtServerInit in universal mode, Nuxt will call it with the Nuxt context. You can use this function to load data or dispatch other actions:
const actions = {
nuxtServerInit({ dispatch }, ctx) {
dispatch('loadAirports');
}
}
Note that nuxtServerInit is only called server side (or during compile-time if statically generating). You can implement a similar nuxtClientInit by creating a client plugin that immediately dispatches to the store.
https://nuxtjs.org/docs/directory-structure/store/#the-nuxtserverinit-action
This is actually quite simple to do in NuxtJs.
First of all define your initial state:
export const state = () => ({
airports: [],
})
Since Nuxt gives access to nuxtServerInit inside of your file you can do this:
//NOTE this only works when mode is set to universal inside of your nuxt config
export const actions = {
async nuxtServerInit({ commit }) {
const data = await this.$axios.$get(`your-api`)
// you can do all of your logic here before commiting
commit('setAirports', data)
}
}
than all you have left to do is create a mutatation to fill the state with your data
export const mutations = {
setAirports(state, payload) {
state.airports.push(...payload)
},
}
Related
This component is for counting views at page level in Next.js app deployed on AWS Lambda
function ViewsCounter({ slug }: { slug: string }) {
const { data } = useSWR(`/api/views/${slug}`, fetcher);
const views = new Number(data?.total);
useEffect(() => {
const registerView = () =>
fetch(`/api/views/${slug}`, { method: "POST" })
.catch(console.log);
registerView();
}, [slug]);
return (
<>
{views}
</>
);
}
This one is for displaying views on homepage
function ViewsDisplay({ slug }: { slug: string }) {
const { data } = useSWR(`/api/views/${slug}`, fetcher);
const views = new Number(data?.total);
return (
<>
{views}
</>
);
}
While it works as expected on localhost, looks like it displays only the first fetched value and doesn't revalidate it for some reason.
When visiting the page, Counter is triggered correctly and the value is changed in DB.
Probably it has something to do with mutating, any hints are appreciated.
useSWR won't automatically refetch data by default.
You can either enable automatic refetch using the refreshInterval option.
const { data } = useSWR(`/api/views/${slug}`, fetcher, { refreshInterval: 1000 });
Or explicitly update the data yourself using a mutation after the POST request to the API.
function ViewsCounter({ slug }: { slug: string }) {
const { data, mutate } = useSWR(`/api/views/${slug}`, fetcher);
const views = new Number(data?.total);
useEffect(() => {
const registerView = () =>
fetch(`/api/views/${slug}`, { method: "POST" })
.then(() => {
mutate();
})
.catch(console.log);
registerView();
}, [slug]);
return (<>{views}</>);
}
Take a look at my Slice below
import { createSlice, createAsyncThunk } from "#reduxjs/toolkit";
import axios from "axios";
const KEY = process.env.REACT_APP_API_KEY
const BASE_URL = process.env.REACT_APP_BASE_URL
const API = `${BASE_URL}/countrymap`
const initialState = {
mapdata:[],
status: 'idle',
error:null
}
export const fetchMapData = createAsyncThunk(
'mapdata/fetchMapData',
async (id) => {
try {
const response = await axios.get(
API,
{
headers: {
'Content-Type': 'application/json',
'X-API-KEY': KEY,
},
params: {
titleId: id,
}
}
)
return response.data.Item;
} catch (error) {
console.error('API call error:', error.message);
}
}
)
const mapSlice = createSlice({
name: 'mapdata',
initialState,
reducers:{
},
extraReducers(builder) {
builder
.addCase(fetchMapData.fulfilled, (state, action) => {
state.status = 'succeeded'
//This attempt to make it an array failed with the error
// that the state is not iterable
state.mapdata = [action.payload, ...state]
console.log("map payload: ", state.mapdata);
})
}
})
// SELECTORS
// This works for an array, but the data is originally coming
// in as an object instead
export const allMapData = (state, id) => state.mapdata.mapdata.find(item => item.title_id === id);
export default mapSlice.reducer
for reference, look at these two console logs from two different API calls to two different endpoints from two different slices . Except Media is coming back as an array, and map is an object
I need to either, turn the state.mapdata into an Object to I can use the selector the way it is or re-code the selector so that it doesn't use the .find() function because that's an array function. But either way, it needs to compare the titleId in the data to the id in the params
Sorry for not providing workable code. I would but there is an insane amount of dependencies here
You should use
state.mapdata = [action.payload, ...state.mapdata]
instead of
state.mapdata = [action.payload, ...state]
I am having trouble with my Redux store in cases where I am passing params through a Thunk action. In cases were there is no param, my store is populating correctly. The action is completing successfully and I can see that the data has been returned to the front end by the success / fulfilled message of my action but there is no sign of it going into the store as state.
I had an instance previously where the array list was named incorrectly from the backend however this is not the case this time.
Is there anything that stands out why my store isn't populating with the state data?
action
export const requireUserDiveLogData = createAsyncThunk(
'users/requireData', // action name
// action expects to be called with the name of the field
async (userId) => {
// you need to define a function to fetch the data by field name
const response = await userDiveLogList(userId);
// what we return will be the action payload
return response.data;
},
// only fetch when needed: https://redux-toolkit.js.org/api/createAsyncThunk#canceling-before-execution
{
// _ denotes variables that aren't used - the first argument is the args of the action creator
condition: (_, { getState }) => {
const { users } = getState(); // returns redux state
// check if there is already data by looking at the didLoadData property
if (users.didLoadDiveLogData) {
// return false to cancel execution
return false;
}
}
}
)
reducer
export const userSlice = createSlice({
name: 'users',
initialState: {
userDiveLogList: [],
didLoadDiveLogData: false,
},
reducers: {
[requireUserDiveLogData.pending.type]: (state) => {
state.didLoadDiveLogData = true;
},
[requireUserDiveLogData.fulfilled.type]: (state, action) => {
return {
...state,
...action.payload
}
},
}
})
You should use extraReducers rather than reducers to handle actions produced by createAsyncThunk and createAction functions.
Besides, Redux Toolkit's createReducer and createSlice automatically use Immer internally to let you write simpler immutable update logic using "mutating" syntax. You don't need to do the shallow copy work by yourself.
E.g.
// #ts-nocheck
import {
configureStore,
createAsyncThunk,
createSlice,
} from '#reduxjs/toolkit';
async function userDiveLogList(userId) {
return { data: { userDiveLogList: [1, 2, 3] } };
}
export const requireUserDiveLogData = createAsyncThunk(
'users/requireData',
async (userId) => {
const response = await userDiveLogList(userId);
return response.data;
},
{
condition: (_, { getState }) => {
const { users } = getState();
if (users.didLoadDiveLogData) {
return false;
}
},
}
);
const userSlice = createSlice({
name: 'users',
initialState: {
userDiveLogList: [],
didLoadDiveLogData: false,
},
reducers: {},
extraReducers: (builder) => {
builder
.addCase(requireUserDiveLogData.pending, (state) => {
state.didLoadDiveLogData = true;
})
.addCase(requireUserDiveLogData.fulfilled, (state, action) => {
state.userDiveLogList = action.payload.userDiveLogList;
});
},
});
const store = configureStore({
reducer: {
users: userSlice.reducer,
},
});
store.dispatch(requireUserDiveLogData()).then(() => {
console.log(JSON.stringify(store.getState(), null, 2));
});
Output in the console:
{
"users": {
"userDiveLogList": [
1,
2,
3
],
"didLoadDiveLogData": true
}
}
I have a function "sendMessage" in React class:
class MessageForm extends React.Component {
...
sendMessage = async () => {
const { message } = this.state;
if (message) {
this.setState({ loading: true });
if (this.props.isPrivateChannel === false) {
socket.emit("createMessage", this.createMessage(), (response) => {
this.setState({ loading: false, message: "", errors: [] });
});
} else {
if (this.state.channel && this.state.channel._id === undefined) {
socket.emit("createChannelPM", this.state.channel, async (response) => {
const chInfo = { ...response, name: this.props.currentChannel.name };
console.log("chInfo : ", chInfo);
await this.props.setCurrentChannel(chInfo).then((data) => {
if (data) {
console.log("data : ", data);
console.log("this.props.currentChannel : ", this.props.currentChannel);
}
});
});
}
...
function mapStateToProps(state) {
return {
isPrivateChannel: state.channel.isPrivateChannel,
currentChannel: state.channel.currentChannel,
};
}
const mapDispatchToProps = (dispatch) => {
return {
setCurrentChannel: async (channel) => await dispatch(setCurrentChannel(channel)),
}
};
Here, in sendMessage function, I retrieve "response" from socket.io, then put this data into variable "chInfo" and assign this to Redux state, then print it right after assinging it.
And Redux Action function, "setCurrentChannel" looks like:
export const setCurrentChannel = channel => {
return {
type: SET_CURRENT_CHANNEL,
payload: {
currentChannel: channel
}
};
};
Reducer "SET_CURRENT_CHANNEL" looks like:
export default function (state = initialState, action) {
switch (action.type) {
case SET_CURRENT_CHANNEL:
return {
...state,
currentChannel: action.payload.currentChannel
};
...
The backend Socket.io part look like (I use MongoDB):
socket.on('createChannelPM', async (data, callback) => {
const channel = await PrivateChannel.create({
...data
});
callback(channel)
});
The console.log says:
Problem : The last output, "this.props.currentChannel" should be same as the first output "chInfo", but it is different and only print out previous value.
However, in Redux chrome extension, "this.props.currentChannel" is exactly same as "chInfo":
How can I get and use newly changed Redux states immediately after assinging it to Redux State?
You won't get the updated values immediately in this.props.currentChannel. After the redux store is updated mapStateToProps of MessageForm component is called again. Here the state state.channel.currentChannel will be mapped to currentChannel. In this component you get the updated props which will be accessed as this.props.currentChannel.
I believe you want to render UI with the latest data which you which you can do.
I have setup vuex and i would like to later fetch the data and update my form model but this fails
In my vuex
//state
const state = {
profile: [],
}
//getter
const getters = {
profileDetails: state => state.profile,
}
//the actions
const actions = {
getProfileDetails ({ commit }) {
axios.get('/my-profile-details')
.then((response) => {
let data = response.data;
commit(types.RECEIVED_USERS, {data});
},
);
}
}
const mutations = {
[types.RECEIVED_USERS] (state, { data }) {
state.profile = data;
state.dataloaded = true;
},
}
Now in my vue js file
export default{
data: () => ({
profile_form:{
nickname:'',
first_name:'',
last_name:'',
email:''
}
}),
computed:{
...mapGetters({
user: 'profileDetails',
}),
},
methods:{
setUpDetails(){
this.profile_form.email = this.user.email; //the value is always undefined
}
},
mounted(){
this.$store.dispatch('getProfileDetails').then(
(res)=>{
console.log(res); //this is undefined
this.setUpDetails(); ///this is never executed
}
);
this.setUpDetails(); //tried adding it here
}
By checking with the vue developer tools i can see that the vuex has data but my component cant fetch the data in vuex after calling the dispatch in the action to fetch the data.
Where am i going wrong.
Nb: AM using the data to update a form like this
<input v-model="profile_form.email" >
Your mounted method expects a return (res) from getProfileDetails, but the action isn't returning anything, so you could simply try
const actions = {
getProfileDetails ({ commit }) {
return axios.get('/my-profile-details')
.then((response) => {
let data = response.data;
commit(types.RECEIVED_USERS, {data});
return data // put value into promise
},
);
}
}
However, it's more usual to commit to store from within the action (which you are doing) and let the component get the new values from a getter (which you have) - i.e one-way-data-flow.
This is how I'd set it up.
data: () => ({
profile_form:{
nickname:'',
first_name:'',
last_name:'',
email:''
}
}),
mounted(){
this.$store.dispatch('getProfileDetails')
}
computed: {
...mapGetters({
user: 'profileDetails',
}),
}
watch: {
user (profileData){
this.profile_form = Object.assign({}, profileData);
}
},
methods:{
submit(){
this.$store.commit('submituser', this.profile_form)
}
},