Develop Reference

Vue 3's Provide / Inject using the Options API

I've been trying to follow the documentation for the API on the Vue 3 website which says to use app.provide('keyName',variable) inside your main.js file like so:
import App from './App.vue'
import { createApp } from 'vue'
import axios from 'axios'
const app = createApp(App)
app.provide('axios', axios)
app.use('Vue')
app.mount('#app')
Then inject and use it in your child component like so:
export default {
inject: ['axios'],
...
createUser (data) {
return this.axios.post('/users', data)
}
}
However doing so just gives me this error in my console:
Uncaught TypeError: Cannot read properties of undefined (reading 'post')
Is there anything I'm missing? I didn't see any about an import unless you're using the Composition API. Can provide / inject be called from within a .js file? I would expect so as long as its within a export default {} statement
Ive tried following the API to a "T" but it simply refuses to work for me. Also tried searching the web for solutions but everything I've found says what I'm doing should be working just fine.

It works, see the playground.
But is not absolutely necessary, since with the browser library version axios is globally defined and could be accessed also without inject
You could also save yourself some time with the vue-axios plugin.
Example
const { createApp } = Vue;
const myComponent = {
inject: ['axios'],
created() {
this.axios.get('/')
.then(function (response) {
console.log(response);
})
.catch(function (error) {
console.log(error);
})
},
template: '<div>My Component</div>'
}
const App = {
components: {
myComponent
}
}
const app = createApp(App)
app.provide('axios', axios)
app.mount('#app')
<div id="app">
<my-component></my-component>
</div>
<script src="https://unpkg.com/vue#3/dist/vue.global.js"></script>
<script src="https://unpkg.com/axios#1.3.1/dist/axios.min.js"></script>

How to properly install a Pinia Store?

I'm building a Vue 3 app using the OptionsAPI along with a Pinia Store but I frequently run into an issue stating that I'm trying to access the store before createPinia() is called.
I've been following the documentation to use the Pinia store outside components as well, but maybe I'm not doing something the proper way.
Situation is as follows:
I have a login screen (/login) where I have a Cognito session manager, I click a link, go through Cognito's signup process, and then get redirected to a home route (/), in this route I also have a subroute that shows a Dashboard component where I make an API call.
On the Home component I call the store using useMainStore() and then update the state with information that came on the URL once I got redirected from Cognito, and then I want to use some of the state information in the API calls inside Dashboard.
This is my Home component, which works fine by itself, due to having const store = useMainStore(); inside the mounted() hook which I imagine is always called after the Pinia instance is created.
<template>
<div class="home">
<router-view></router-view>
</div>
</template>
<script>
import {useMainStore} from '../store/index'
export default {
name: 'Home',
components: {
},
mounted() {
const store = useMainStore();
const paramValues = {}
const payload = {
// I construct an object with the properties I need from paramValues
}
store.updateTokens(payload); // I save the values in the store
},
}
</script>
Now this is my Dashboard component:
<script>
import axios from 'axios'
import {useMainStore} from '../store/index'
const store = useMainStore();
export default {
name: "Dashboard",
data() {
return {
user_data: null,
}
},
mounted() {
axios({
url: 'myAPIUrl',
headers: { 'Authorization': `${store.token_type} ${store.access_token}`}
}).then(response => {
this.user_data = response.data;
}).catch(error => {
console.log(error);
})
},
}
</script>
The above component will fail, and throw an error stating that I'm trying to access the store before the instance is created, I can solve this just by moving the store declaration inside the mounted() hook as before, but what if I want to use the store in other ways inside the component and not just in the mounted hook? And also, why is this failing? By this point, since the Home component already had access to the store, shouldn't the Dashboard component, which is inside a child route inside Home have the store instance already created?
This is my main.js file where I call the createPinia() method.
import { createApp } from 'vue'
import { createPinia } from 'pinia'
import App from './App.vue'
import router from './router'
const pinia = createPinia();
createApp(App).use(router).use(pinia).mount('#app')
And the error I get is:
Uncaught Error: [🍍]: getActivePinia was called with no active Pinia. Did you forget to install pinia?
My Store file:
import { defineStore } from 'pinia';
export const useMainStore = defineStore('main', {
state: () => ({
access_token: sessionStorage.getItem('access_token') || '',
id_token: sessionStorage.getItem('id_token') || '',
token_type: sessionStorage.getItem('token_type') || '',
isAuthenticated: sessionStorage.getItem('isAuthenticated') || false,
userData: JSON.parse(sessionStorage.getItem('userData')) || undefined
}),
actions: {
updateTokens(payload) {
this.id_token = payload.id_token;
this.access_token = payload.access_token;
this.token_type = payload.token_type
sessionStorage.setItem('id_token', payload.id_token);
sessionStorage.setItem('access_token', payload.access_token);
sessionStorage.setItem('token_type', payload.token_type);
sessionStorage.setItem('isAuthenticated', payload.isAuthenticated);
},
setUserData(payload) {
this.userData = payload;
sessionStorage.setItem('userData', JSON.stringify(payload));
},
resetState() {
this.$reset();
}
},
})

It's possible but not common and not always allowed to use use composition functions outside a component. A function can rely on component instance or a specific order of execution, and current problem can happen when it's not respected.
It's necessary to create Pinia instance before it can be used. const store = useMainStore() is evaluated when Dashboard.vue is imported, which always happen before createPinia().
In case of options API it can be assigned as a part of component instance (Vue 3 only):
data() {
return { store: useMainStore() }
},
Or exposed as global property (Vue 3 only):
const pinia = createPinia();
const app = createApp(App).use(router).use(pinia);
app.config.globalProperties.mainStore = useMainStore();
app.mount('#app');

Since you're using Vue 3, I suggest you to use the new script setup syntax:
<script setup>
import { reactive, onMounted } from 'vue'
import axios from 'axios'
import { useMainStore } from '../store'
const store = useMainStore();
const data = reactive({
user_data: null
})
onMounted (async () => {
try {
const {data: MyResponse} = await axios({
method: "YOUR METHOD",
url: 'myAPIUrl',
headers: { 'Authorization': `${store.token_type} ${store.access_token}`}
})
data.user_data = MyResponse
} catch(error){
console.log(error)
}
})
</script>
Using setup you can define that store variable and use it through your code.

everyone after a lot of research I found the answer to this issue,
you must pass index.ts/js for const like below:
<script lang="ts" setup>
import store from '../stores/index';
import { useCounterStore } from '../stores/counter';
const counterStore = useCounterStore(store());
counterStore.increment();
console.log(counterStore.count);
</script>

Access to main Vue instance in App.vue script

In Vue2, I'm trying to set up an axios interceptor in my App.vue file to trap any responses that come back 401 from my API so I can redirect the user to the Vue route /sign-in. My code works, but I rely on storing the Vue instance created in main.js in window.appvue.
In main.js:
window.appvue = new Vue({
router,
render: (h) => h(App),
}).$mount("#app");
In App.vue:
<script>
import...
export default { ... }
export const $axios = axios.create();
$axios.interceptors.response.use(
(response) => {
return response;
},
(error) => {
if (error.response.status === 401) {
window.appvue.$router.push("/sign-in");
} else {
return Promise.reject(error);
}
}
);
<script>
I have tried importing $axios from App.vue in main.js and moving the $axios.interceptors.response.use(...) code to that file, but then the interceptor never runs when I have a page where an $axios.get() returns 401.
Is there a way to accomplish this without storing the main Vue instance in window as a global? Or should I just go with what's working and call it a day?
P.S.
I was not aware of the existence of $root, when I asked this question, and I have not tried a version where the code in App.vue uses $root instead of relying on the window.appvue global, but when it comes to accessing the main/root instance of Vue from main.js, $root is definitely preferable to a global.

I managed to avoid using the global by isolating the axios wrapper into its own module/file. Then my .vue files that need axios can import from that instead of from axios directly
In {root}/src/axios.js:
import axios from "axios";
import router from "#/router";
const $axios = axios.create();
$axios.interceptors.response.use(
[stuff that uses router]
);
export default $axios;
Then in my files that need to call to the API:
import $axios from "#/axios.js";
and use $axios instead of axios to make the API call.

inside your main.js try something like this
import router from './router'
import axios from 'axios'
Vue.prototype.axios.interceptors.reponse.use(
res => {
// res stuff here
},
err => {
// error stuff here
if (err.response.status === 401) {
router.push("/sign-in");
} else {
return Promise.reject(err);
}
}
)

TypeError: Webpack imported module is not a function

I have a backend that calculates work shifts.
I am trying to post some required user input with a module in services/shifts.
The getAll method works fine, but posting throws an error
TypeError: _services_shifts__WEBPACK_IMPORTED_MODULE_2__.default.postData is not a function
Shiftservice module:
import axios from 'axios'
const baseUrl = '...'
const getAll = () => {
const request = axios.get(baseUrl)
return request.then(response => response.data)
}
const postData = newObject => {
const request = axios.post(baseUrl, newObject)
return request.then(response => response.data)
}
export default {getAll, postData}
I have a button that triggers the following calling code on click:
import shiftService from './services/shifts'
const postData = (event) => {
event.preventDefault()
const sampleObject = {
sampleField: sample
}
shiftService
.postData(sampleObject)
.then(returnedData => {
console.log(returnedData)
})
}
When execution reaches shiftService.postData, the error is thrown.
I am really confused since I am basically copying some older project of mine which works, but here I just don't find the problem. Thank you in advance for helping a newcomer!

Modules provide special export default (“the default export”) syntax to make the “one thing per module” way look better.There may be only one export default per file.And we may neglect the name of the class in the following example.
//Module1
export default class{
}
And then import it without curly braces with any name:
//Module2
import anyname from './Module1'
Your scenario is different having two functions.You can either export default one function
export default getAll
and normal export the other function.
export postData
and when importing
import{ default as getAll,postData} from './yourModule'
OR
Remove default here in Shiftservice module and export normally:
import axios from 'axios'
const baseUrl = '...'
const getAll = () => {
const request = axios.get(baseUrl)
return request.then(response => response.data)
}
const postData = newObject => {
const request = axios.post(baseUrl, newObject)
return request.then(response => response.data)
}
export {getAll, postData}
Importing in your module
import {getAll,PostData} from './Module1'
or
import * as shiftService from './Module1'
and then use shiftServer.postData().....

Okay, I am embarrassed of the solution. I was just editing an earlier version of shiftService from a wrong folder, and the imported service only had the get method in it...
So my code actually works if placed correctly. Thank you for your time, and thanks for sharing alternative ways that must work aswell.

I think its becuse your declaring the function as arrow functions
and export it this way:
export default {getAll, postData}
you need to declare them as a normal functions
function postData(){
}
that should work

Reach router navigate updates URL but not component

I'm trying to get Reach Router to navigate programmatically from one of my components. The URL is updated as expected however the route is not rendered and if I look at the React developer tools I can see the original component is listed as being displayed.
If I refresh the page once at the new URL then it renders correctly.
How can I get it to render the new route?
A simplified example is shown below and I'm using #reach/router#1.2.1 (it may also be salient that I'm using Redux).
import React from 'react';
import { navigate } from '#reach/router';
const ExampleComponent = props => {
navigate('/a/different/url');
return <div />;
};
export default ExampleComponent;

I was running into the same issue with a <NotFound defualt /> route component.
This would change the URL, but React itself didn't change:
import React from "react";
import { RouteComponentProps, navigate } from "#reach/router";
interface INotFoundProps extends RouteComponentProps {}
export const NotFound: React.FC<INotFoundProps> = props => {
// For that it's worth, neither of these worked
// as I would have expected
if (props.navigate !== undefined) {
props.navigate("/");
}
// ...or...
navigate("/", { replace: true });
return null;
};
This changes the URL and renders the new route as I would expect:
...
export const NotFound: React.FC<INotFoundProps> = props => {
React.useEffect(() => {
navigate("/", { replace: true });
}, []);
return null;
};

Could it be that you use #reach/router in combination with redux-first-history? Because I had the same issue and could solve it with the following configuration of my historyContext:
import { globalHistory } from "#reach/router";
// other imports
const historyContext = createReduxHistoryContext({
// your options...
reachGlobalHistory: globalHistory // <-- this option is the important one that fixed my issue
}
More on this in the README of redux-first-history

The same issue happens to me when I'm just starting to play around with Reach Router. Luckily, found the solution not long after.
Inside Reach Router documentation for navigate, it is stated that:
Navigate returns a promise so you can await it. It resolves after React is completely finished rendering the next screen, even with React Suspense.
Hence, use await navigate() work it for me.
import React, {useEffect} from 'react';
import {useStoreState} from "easy-peasy";
import {useNavigate} from "#reach/router";
export default function Home() {
const {isAuthenticated} = useStoreState(state => state.auth)
const navigate = useNavigate()
useEffect(()=> {
async function navigateToLogin() {
await navigate('login')
}
if (!isAuthenticated) {
navigateToLogin()
}
},[navigate,isAuthenticated])
return <div>Home page</div>
}

Try and use gatsby navigate. It uses reach-router. It solved my problem
import { navigate } from 'gatsby'